Pulp Therapy for the Primary Dentition










CHAPTER 21 Dental Materials 301
and an increase in wear. To compensate for polymerization shrinkage,
some of the Bis-GMA resin in the composite is prepolymerized
by the manufacturer.
More highly lled (>70% by volume) microlled resin–based
composites are available and can be eectively used in areas where
greater wear and stress is anticipated.
Macrolled Resin–Based Composite
Macrolled resin–based composite (Fig. 2.12B) has silane-treated
ller particles (approximately 80% by volume) in a Bis-GMA
resin. e particle sizes are much larger than those found in
microlled systems. Although these particles are larger than those
found in the microlled composites, they are smaller than the
conventional resin-based composite particles. e high ller-particle
percentage increases wear resistance. Because most of these resin
composites are used for posterior restorations, the material is usually
radiopaque from the ller type.
Hybrid Resin–Based Composite
Hybrid resin–based composites (Fig. 21.12C) have a combination
of small and large particles, representing the size of the particles
found in microlled and macrolled resin–based composites,
respectively. The high percentage of filler particles provides
strength and wear resistance, yet the smaller ller particles allow
for particles to arrange in close proximity to each other, which
can provide minimal polymerization shrinkage and improved
polishability compared with macrolled composite. ese resin-
based composites are considered for restorations that may have
stress-bearing areas during mastication but must have a well-polished
surface.
Nanolled Resin–Based Composite
Since the introduction of resin-based composites, the size of
filler particles has become smaller. More recently, nanofilled
composites (Fig. 21.12D) that contain very small ller particles
have been introduced. ese resin composites oer the strength
of a highly lled resin as well as polishability due to the small
particles.
Glass Ionomer
Anterior Restorations
Preparations of glass ionomer cements are available in various
shades that can be used for anterior restorations.
64,65
e use of
glass ionomer for anterior restorations is limited to class III and
class V preparations. e low fracture resistance and strength
of mechanical bonding to enamel make its use impractical for
class IV restorations. Retention of glass ionomer restorations
in the restoration of class V preparations, where the gingival
margin is not in enamel, may demonstrate favorable retention
when restored with a glass ionomer rather than a resin-based
composite. The fluoride release from glass ionomer restora-
tions has been shown to inhibit the development of secondary
caries.
66–69
Posterior Restorations
e major disadvantage of glass ionomer cement as a posterior
restorative material is its susceptibility to fracture and wear. Metal
particles have been added to glass ionomer cement to increase
their strength and wear resistance for posterior restorations. Fracture
resistance remains a concern, and critical decisions should be made
when using the material for posterior restorations. Investigations
have demonstrated the clinical success of resin-modied glass
ionomer cement as a posterior restorative material in the primary
dentition.
66,70,71
Again, uoride release and bonding capabilities
are advantages of the glass ionomer cements.
Compomers
Compomers are recommended for use as a pediatric dental
restorative material.
72–75
Compomers are actually a cross between
resin-based composite and glass ionomer cement.
e compomers were developed in the hope of bringing the
favorable properties of resin-based composite—such as wear
resistance, color stability, and polishability—to the glass ionomers.
An acid-base reaction takes place within the compomer material
but is not the primary setting reaction; therefore visible light–
polymerization is necessary to complete the setting reaction.
Compomers are used with methacrylate primers that bond to
enamel, dentin, and the compomer restorative material; therefore
manufacturers consider the etching of tooth structure before restora-
tion placement optional.
Cements
Cements are frequently used in pediatric dentistry. eir primary
use is for the cementation of stainless steel crowns and orthodontic
bands. Zinc oxide–eugenol and glass ionomer are the cements
most commonly used. ese cements were previously discussed
in the section “Bases and Liners.” e particles in glass ionomer
cement are usually larger than those found in glass ionomer bases.
ere is less particle surface area available for reaction in the cement;
therefore the cement sets more slowly than the base, allowing more
working time. e importance of accuracy in the liquid/powder
ratio of glass ionomer cement has been discussed. Encapsulated,
premeasured cement is available and may be considered for clinical
use. Automix syringe tips are available for the resin-modied glass
ionomer materials as well.
Bioactive cements have more recently become available in the
marketplace. ese cements have glass particles incorporated into
a resin matrix and have the advantage of bonding to tooth structure.
e cements release calcium and uoride. Manufacturers recommend
these cements for cementing stainless steel, porcelain, and zirconia
crowns.
e various cements most commonly used in pediatric dentistry
and their clinical considerations are noted in Tables 21.1 and 21.2.
Monolithic Zirconia
Monolithic zirconia was introduced to dentistry almost two decades
ago; more recently, it has been used for complete coverage crowns.
e zirconia ceramic crown is very strong in exural and compressive
strength.
76
A highly polished, glossy surface is very favorable to
gingival tissue.
76
Monolithic zirconia crowns are now available for
the esthetic restoration of primary anterior and posterior teeth.
An in vitro study has demonstrated that natural teeth opposing
zirconia crowns have a more favorable wear than natural teeth
opposing porcelain crowns.
77
Currently, manufacturers recommend
the use of resin-modied glass ionomer cement for zirconia,
including bioactive cements (Bio Cem, NuSmile, Houston, TX;
Ceramir, Doxa Dental Inc., Chicago, IL; Activa Bio Active Cement,
Pulpdent Corporation, Watertown, MA).

302 Part 3 The Primary Dentition Years: Three to Six Years
19. Swift EJ. Dentin/enamel adhesives: review of the literature. Pediatr
Dent. 2002;24:456–461.
20. Fuks A. e use of amalgam in pediatric dentistry. Pediatr Dent.
2002;24:448–455.
21. Osborne JW, Summitt JB, Roberts HW. e use of dental amalgam
in pediatric dentistry: review of the literature. Pediatr Dent.
2002;24:439–447.
22. Osborne JW. ree-year clinical performance of eight amalgam alloys.
Am J Dent. 1990;3:157–159.
23. Council on Dental Materials and Devices. Revised American Dental
Association Specication No. 1 for Alloy for Dental Amalgam. J Am
Dent Assoc. 1977;95:614–617.
24. Burgess JO, Walker R, Davidson BS. Posterior resin-based composite:
review of the literature. Pediatr Dent. 2002;24:465–479.
25. Donly KJ, Garcia-Godoy F. e use of resin-based composite in
children. Pediatr Dent. 2002;24:480–488.
26. Bowen RL. Dental lling material comprising vinyl-silane treated fused
silica and a binder consisting of the reaction product of bisphenol
and glycidyl methacrylate; 1962. U.S. Patent #3066112A.
27. Phillips RW, Swartz ML, Norman RD. Materials for the Practicing
Dentist. St Louis: Mosby; 1969:182–191.
28. Bayne SC, Taylor DF, Sturdevant JR, et al. Protection theory for
composite wear based on 5-year clinical results. J Dent Res. 1988;67
(Abstract 60):120.
29. Ruyter IE. Polymerization and conversion in composite resins. In:
Taylor DF, ed. Proceedings of the International Symposium on Posterior
Composite Resins (Chapel Hill, NC, October 1982). Chapel Hill,
NC: University of North Carolina; 1984:255–286.
30. Asmussen E. Composite restorative resins. Composition versus
wall to wall polymerization contraction. Acta Odontol Scand.
1975;33:337–344.
31. Bowen RL, Rapson JE, Dickson G. Hardening shrinkage and hygro-
scopic expansion of composite resins. J Dent Res. 1982;61:654–658.
32. Donly KJ, Jensen ME. Posterior composite polymerization shrinkage
in primary teeth: an in vitro comparison of three techniques. Pediatr
Dent. 1986;8:209–212.
33. Eick DJ, Welch FH. Polymerization shrinkage of composite resins
and its possible inuence on postoperative sensitivity. Quintessence
Int. 1986;77:103–111.
34. Jorgensen KD, Asmussen E, Shimokobe H. Enamel damage caused
by contracting restorative resins. Scand J Dent Res. 1975;83:120–122.
35. Segura A, Donly KJ. Posterior composite polymerization shrinkage
recovery following hygroscopic expansion. J Oral Rehabil.
1993;20:495–499.
References
1. Donly KJ, Wild TW, Jensen ME. Posterior composite class II
restorations: in vitro comparison of preparation designs and restoration
techniques. Dent Mater. 1990;6:88–93.
2. Pereira JC, Mano AP, Franco EB, et al. Clinical evaluation of Dycal
under amalgam restorations. Am J Dent. 1990;3:67–70.
3. Straon LH, Corpron RL, Bruner FW, et al. Twenty-four-month
clinical trial of visible-light activated cavity liner in young permanent
teeth. J Dent Child. 1991;58:124–128.
4. Manders CA, Garcia-Godoy F, Barnwell GM. Eect of a copal varnish,
ZOE or glass ionomer cement bases on microleakage of amalgam
restorations. Am J Dent. 1990;3:63–66.
5. Heys RJ, Fitzgerald M. Microleakage of three cement bases. J Dent
Res. 1991;70:55–58.
6. Donly KJ, Ingram C. An in vitro caries inhibition of photopolymerized
glass ionomer liners. ASDC J Dent Child. 1997;64:128–130.
7. Garcia-Godoy F, Jensen ME. Articial recurrent caries in glass
ionomer–lined amalgam restorations. Am J Dent. 1990;3:89–93.
8. Hicks MJ, Flaitz CM, Silverstone LM. Secondary caries forma-
tion in vitro around glass ionomer restoration. Quintessence Int.
1986;17:527–532.
9. Jensen ME, Wefel JS, Hammesfahr PD. Fluoride-releasing liners: in
vitro recurrent caries. Gen Dent. 1991;39:12–17.
10. Diaz-Arnold AM, Holmes DC, Wistrom DW, et al. Short-term
uoride release/uptake of glass ionomer restoratives. Dent Mater.
1995;11:96–101.
11. Forsten L. Fluoride release and uptake by glass ionomers and related
materials and its clinical eect. Biomaterials. 1998;19:503–508.
12. Forsten L. Resin-modied glass ionomer cements: uoride release
and uptake. Acta Odontol Scand. 1995;53:222–225.
13. Skartveit L, Tveit AB, Tøtdal B, et al. In vivo uoride uptake in
enamel and dentin from uoride-containing materials. ASDC J Dent
Child. 1990;58:97–100.
14. Donly KJ. Enamel and dentin demineralization inhibition of uoride-
releasing materials. Am J Dent. 1994;7:275–278.
15. Grin F, Donly KJ, Erickson RC. Caries inhibition of three
uoride-releasing liners. Am J Dent. 1992;5:293–295.
16. Mitra SB. Property comparisons of a light-cure and a self-cure glass
ionomer liner. J Dent Res. 1989;68A(Abstract 740):274.
17. Erickson RL. Mechanism and clinical implications of bond formation
for two dentin bonding agents. Am J Dent. 1989;2:117–123.
18. Garcia-Godoy F, Donly KJ. Dentin/enamel adhesives in pediatric
dentistry. Pediatr Dent. 2002;24:462–464.
Cement Composition
Working
Time Setting Time
Compressive
Strength
Bond Strength
to Dentin
Release of
Fluoride
Pulpal
Response
Removal
of Excess
Ideal Medium Short-medium Very high High Yes None Easy
Glass ionomer Silicate glass
containing Ca, Al, F
Polycarboxylic acid
Short-medium Short High Medium Yes Low Moderate
Bioactive High Medium High High Yes None Moderate
Zinc oxide and
eugenol
Zinc oxide
Eugenol
Long Medium Low-medium None No None Easy
Reinforced zinc
oxide and
eugenol
Zinc oxide reinforced
with alumina or
polymer eugenol
Long Medium-long Low-medium None No None Easy
Modied from Farah JW, Powers JM. Cements. Dent Advisor. 1985;2(1):3.
Comparison of Dental Cements
TABLE
21.2

CHAPTER 21 Dental Materials 303
57. Phillips RW, Lutz F. Status reports on posterior composites. Council
on Dental Materials, Instruments, and Equipment. J Am Dent Assoc.
1983;107:74–76.
58. Derkson GD, Richardson AS, Waldman RJ. Clinical evaluation of
composite resin and amalgam posterior restorations: two year results.
J Can Dent Assoc. 1983;4:277–279.
59. Ripa LW. Sealants revisited: an update of the eectiveness of pit-
and-ssure sealants. Caries Res. 1993;27(suppl 1):77–82.
60. Simonsen RJ. Retention and eectiveness of dental sealants after
fteen years. J Am Dent Assoc. 1991;122:34–42.
61. Wright JT, Crall JJ, Fontana M, et al. Evidence based clinical practice
guideline for the use of pit and ssure sealants: a report of the
American Dental Association and the American Academy of Pediatric
Dentistry. J Am Dent Assoc. 2016;147(8):672–682.
62. Hicks MJ, Flaitz CM. Caries-like lesion formation around uoride-
releasing sealant and glass ionomer. Am J Dent. 1992;5:329–334.
63. Jensen ME, Wefel JS, Triolo PT, et al. Eect of a uoride-releasing
ssure sealant on articial enamel caries. Am J Dent. 1990;3:75–78.
64. Berg JH. Glass ionomer cements. Pediatr Dent. 2002;24:430–438.
65. Croll TP, Nicholson JW. Glass ionomer cements in pediatric dentistry:
review of the literature. Pediatr Dent. 2002;24:423–429.
66. Donly KJ, Segura A, Kanellis M, et al. Clinical performance and
caries inhibition of resin-modied glass ionomer cement and amalgam
restorations. J Am Dent Assoc. 1999;130:1459–1466.
67. Ewoldsen H, Herwig L. Decay-inhibiting restorative materials: past
and present. Compend Contin Educ Dent. 1998;19:981–992.
68. Souto M, Donly KJ. Caries inhibition of glass ionomers. Am J Dent.
1994;7:122–124.
69. ten Cate JM, van Duinen RN. Hypermineralization of dentinal
lesions adjacent to glass-ionomer cement restorations. J Dent Res.
1995;74:1266–1271.
70. Croll TP, Bar Zion Y, Segura A, et al. Clinical performance of
resin-modied glass ionomer cement restorations in primary teeth:
a retrospective evaluation. J Am Dent Assoc. 2001;132:1110–1116.
71. Mjör IA, Dahl JE, Moorhead JE. Placement and replacement
of restorations in primary teeth. Acta Odontol Scand. 2002;60:25–28.
72. Hickel R. Glass ionomer, cements, hybrid-ionomers and compomers.
Long term clinical evaluation. Trans Acad Dent Mater. 1996;9:105–112.
73. Marks LA, Weerheijm KL, van Amerongen WE, et al. Dyract versus
Tytin class II restorations in primary molars: 36 months evaluation.
Caries Res. 1999;33:387–392.
74. Peters MCRB, Roeters FJM. Clinical performance of a new compomer
restorative in pediatric dentistry. J Dent Res. 1994;73A(Abstract 34):
106.
75. Roeters JJ, Frankenmolen F, Burgersdijk RC, et al. Clinical evaluation
of Dyract in primary molars: 3-year results. Am J Dent.
1998;11:143–148.
76. Malkondu Ö, Tinastepe N, Akan E, et al. An overview of mono-
lithic zirconia in dentistry. Biotechnol Biotechnol Equip. 2016;30:
644–652.
77. Jung YS, Lee JW, Choi YJ, et al. A study on the in-vitro wear of the
natural tooth structure by opposing zirconia on dental porcelain. J
Adv Prosthodont. 2010;2:111–115.
36. Craig RG. Chemistry, composition and properties of composite
resins. Dent Clin North Am. 1981;25:219–239.
37. Ruyter IE. Monomer systems and polymerization. In: Vanherle C,
Smith DC, eds. Posterior Composite Resin Dental Restorative Materials.
Utrecht, Netherlands: Peter Szulc; 1985:109–135.
38. Smith DC. Posterior composite dental restorative material: materials
development. In: Vanherle G, Smith DC, eds. Posterior Composite
Resin Dental Restorative Materials. Utrecht, Netherlands: Peter Szulc;
1985:47–60.
39. Z250. Material Safety Data Sheet. St Paul, MN: 3M ESPE.
40. Weinmann W, alacker C, Guggenberger R. Siloranes in dental
composites. Dent Mater. 2005;21:68–74.
41. Van Dijken JWV, Lindberg A. Clinical eectiveness of a low shrinkage
composite. A ve-year study. J Adhes Dent. 2009;11:143–148.
42. Pilo R, Oelgiesser D, Cardash HS. A survey of output intensity and
potential for depth of cure among light-curing units in clinical use.
J Dent. 1999;27:235–241.
43. Flury S, Hayoz S, Peutzfeldt A, et al. Depth of cure of resin composites.
Is the ISO 4049 method suitable for bulk-ll materials? Dent Mater.
2012;28:521–528.
44. El-Safty S, Silikas N, Watts DC. Creep deformation of restorative
resin-composites intended for bulk-ll placement. Dent Mater.
2012;28:928–935.
45. Burgess J, Cakir D. Comparative properties of low-shrinkage composite
resins. Compend Contin Educ Dent. 2010;31:10–15.
46. Ilie N, Hickel R. Investigations on a methacrylate-based owable
composite based on the SDR technology. Dent Mater. 2011;27:348–355.
47. Czasch P, Ilie N. In vitro comparison of mechanical properties and
degree of cure of bulk-fill composites. Clin Oral Investig.
2013;17:227–235.
48. Peutzfeldt A. Resin composites in dentistry: the monomer systems.
Eur J Oral Sci. 1997;105:97–116.
49. Moszner N, Fischer UK, Angermann J, et al. A partially aromatic
urethane as a new substitute for Bis-GMA in restorative composites.
Dent Mater. 2008;24:694–699.
50. Giachetti L, Bertini F, Bambi C, et al. A rational use of dental
materials in posterior direct resin restorations in order to control
polymerization shrinkage stress. Minerva Stomatol. 2007;56:129–138.
51. Eames WB, Strain JD, Weitman RT, et al. Clinical comparison of
composite, amalgam, and silicate restorative materials. J Am Dent
Assoc. 1974;89:1111–1117.
52. Leinfelder KF, Sluder TB, Santos JF, et al. Five-year clinical evaluation
of anterior and posterior restorations of composite resin. Oper Dent.
1980;5(2):57–65.
53. Osborne JW, Gale EN, Ferguson GW. One-year and two-year clinical
evaluation of composite resin vs. amalgam. J Prosthet Dent.
1973;30:795–800.
54. Phillips RW. Observations on a composite resin for class II restorations:
two-year report. J Prosthet Dent. 1972;28:164–169.
55. Leinfelder KF, Roberson TM. Clinical evaluation of posterior composite
resins. Gen Dent. 1983;31:276–280.
56. Jaarda MJ, Wang RF, Lang BR. A regression analysis of ller particle
content to predict composite wear. J Prosthet Dent. 1997;77:57–67.

304
22
Restorative Dentistry for the
Primary Dentition
WILLIAM F. WAGGONER AND TRAVIS NELSON
CHAPTER OUTLINE
Instrumentation and Caries Removal
Anatomic Considerations of Primary Teeth
Isolation in Pediatric Restorative Dentistry
Rubber Dam
Alternative Isolation Systems
Restoration of Primary Molars
Adhesive Materials in Primary Molars
Amalgam Use in Primary Molars
General Principles for Intracoronal Restoration of Primary
Posterior Teeth
Restoration of Primary Incisors and Canines
Class III Adhesive Restorations
Class V Restorations for Incisors and Canines
Full Coronal Coverage of Incisors
Prosthetic Replacement of Primary Anterior Teeth
tooth structure, uoride release, improved esthetics, reduction of
mercury exposure, and conservation of tooth structure. None of
the esthetic materials have the track record and proven durability
of amalgam or stainless steel, but when they are placed appropriately,
they can provide useful restorations for the lifespan of the primary
tooth. is chapter will provide information on both the new and
the traditional restorative techniques. For the interested reader, in
2014 the American Academy of Pediatric Dentistry sponsored a
Pediatric Dentistry Restorative Symposium Conference. The
published proceedings
2
include extensive and up-to-date literature
reviews and discussion of pediatric restorative techniques at a greater
depth than can be included in this chapter. In addition, a more
detailed discussion of dental materials used in pediatric restorative
dentistry can be found in Chapter 21.
Instrumentation and Caries Removal
Nearly all instrumentation for restorative procedures is carried out
with the high-speed handpiece (100,000 to 300,000 rpm, either
electric or air turbine) combined with coolant. e coolant may
be water spray or air alone. A water spray coolant is often recom-
mended for high-speed instrumentation; however, there is some
evidence that air coolant alone may be used without creating
irreversible pulpal damage,
3,4
and use of both coolant techniques
is taught in many pediatric dental residency programs.
5
ere are
some instances when a water spray coolant is absolutely necessary.
is is especially true when removing old amalgam restorations
or using diamond burs. Regardless of the coolant used, intermittent
cutting at intervals of a few seconds with light, brushing strokes
should be done to prevent excessive heat generation. Protective
masks and eyewear should always be worn when using the high-speed
air turbine handpiece.
e low-speed handpiece (500 to 15,000 rpm) is most frequently
used primarily for caries removal and occasionally for polishing
and nishing procedures. As with high-speed instrumentation,
light pressure and brushing strokes should be used when using
the low-speed handpiece. Use of hand instrumentation is minimal
in most operative preparations in the primary dentition and is
usually limited to nal caries removal.
Although use of a handpiece for caries removal and cavity
preparation is by far the most popular and frequently used method,
there are at least three other methods of treating carious teeth.
ese are air abrasion, laser treatment, and chemomechanical
methods. With these methods, tooth preparations move from the
P
ediatric restorative dentistry is a dynamic combination of
ever-improving materials and tried-and-true techniques. Many
aspects of primary teeth restoration have not changed for
decades. In 1924 G.V. Black outlined several steps for the prepara-
tion of carious permanent teeth to receive an amalgam restoration.
1
ese steps have been adopted, with slight modication, for the
restoration of primary teeth. Restorative techniques for the primary
dentition using amalgam and stainless steel crowns (SSCs) have
remained relatively consistent for decades (Fig. 22.1). However,
with an increased use of adhesive restorative materials and bonding
systems, there has been a shift to more conservative preparations
and restorations. Materials such as glass ionomers, resin ionomer
products, and improved resin-based composite systems have been
developed that are having a profound impact on the restoration
of primary teeth. In addition, premilled zirconia crowns (ZCs)
now oer an esthetic alternative to SSCs. Unfortunately, long-term
clinical data (i.e., longer than 3 years) regarding many of these
newer materials are limited; but even so, many clinicians are
successfully using these materials with increasing frequency.
e clinician can stay with the proven, successful materials of
the past, such as amalgam and stainless steel, or move to newer,
more esthetic materials that oer advantages such as bonding to

CHAPTER 22 Restorative Dentistry for the Primary Dentition 305
A
D
B
C
Figure 22.1 Traditionally restored primary dentition demonstrating
stainless steel crown (A), preveneered steel crowns (B), class III amalgam
(C), and class II amalgam (D). Note: All white, esthetic alternatives now
exist for each of these restorations.
Conventional
G.V. Black Microdentistry
Extension
for
prevention
Tooth substance saving preparations
Drill and fill
Anesthesia
G.V. Black
Prevention
of
extension
Filling without drilling
Laser/Air abrasion
Chemomechanical
caries removal
No (less) anesthesia
Microdentistry
Pit and
fissure
preparations
Box-only
preparations
Adhesive
cavities
Figure 22.2 Cavity preparation continuum. (Courtesy Dr. Luc Martens,
Ghent, Belgium.)
generated during the procedure, and the fact that it does not
completely eliminate the need for conventional handpieces are
three disadvantages of the system that seem to keep it from gaining
widespread use. Laser techniques have also become popular with
some dental operators. Lasers can be used in children for soft tissue
surgery, caries prevention, caries diagnosis, biostimulation and
pain control, hemostasis during pulpotomy procedures, and cavity
preparation.
8
An erbium:YAG laser can be used in restorative
dentistry for minimally invasive preparation of pits and ssures
and hypoplastic teeth, cavity preparation of all classes (I thorough
V), treatment of deep dentinal caries, and laser-assisted pulp capping.
Some of the advantages of using lasers for cavity preparation include
(1) better patient acceptance because they are quiet, (2) no vibration
and minimal need for use of anesthetic, (3) minimally invasive
cavity preparation because of the selective absorption of laser light
by carious tissue, (4) production of very clean cavity preparations
free of a smear layer, (5) minimal thermal increase in the pulp
chamber, and (6) the production of cavity preparations with a
macroroughened surface that increases surface bonding area for
better adhesion of resin-based materials. Some disadvantages include
(1) a longer learning curve; (2) higher equipment costs ($30,000
to $60,000 for an erbium:YAG laser); (3) need for specialized
training; and (4) possible need for a traditional handpiece to
complete the process, depending on the cavity size and preparation
needed.
9
Chemomechanical caries removal is a noninvasive technique
that eliminates infected dentin via a chemical agent by means of
dissolution. Instead of drilling, a chemical agent such as Carisolv
(MediTeam AB, Göteberg, Sweden) or Papacarie (F&A Laboratorio
Farmaceutico Ltd., São Paulo, Brazil) is applied to the carious
dentin and assisted by hand instruments to remove soft carious
material. is method usually does not require anesthesia, it preserves
sound tooth structure, and it relies on bonded restorative materials
for nal restoration. Drawbacks to this method include an increase
in operator time to remove caries, only certain carious lesions are
suitable for its use, a handpiece may still be necessary to gain access
to the dentinal or interproximal areas, and few long-term data are
available to conrm long-term success of the method.
10
One nal aspect to be considered when discussing tooth prepara-
tion is the use of magnication during operative procedures. Up
until the 1990s the use of magnication for dental procedures by
most practitioners came only with increasing age and failing eyesight,
but now the use of magnifying loupes or microscopes for most
dental procedures is taught from the beginning of most dental
school training. Loupes are available in a wide range of magnica-
tion, but generally a set of loupes with a 2.5× to 3.5× magnication
is recommended for restorative dentistry. e use of magnication
for completing restorative procedures has several advantages, such
as an increase in productivity, an increase in the level of excellence
and condence in dental treatment, an increase in visual diagnostic
abilities, and perhaps most importantly, improvement in operator
posture and comfort to help prevent musculoskeletal disorders
brought about by poor operator positioning.
11
Use of magnication
during cavity preparation has not yet become the standard of care,
but it is highly recommended and will likely become the standard
of care in the next few years.
Anatomic Considerations of Primary Teeth
Although some primary teeth resemble their permanent successors,
they are not miniature permanent teeth. Several anatomic dierences
must be distinguished before restorative procedures are begun (Box
22.1; Fig. 22.3).
traditional, conventional preparations used by G.V. Black to much
more conservative, “tooth-saving” preparations, known as micro-
dentistry or minimally invasive dentistry. Depending on the type
of carious lesions, method of instrumentation, and restorative
material to be used, the clinician can opt for a conventional G.V.
Black type of cavity preparation or for a much more conservative
micropreparation. Fig. 22.2 illustrates a continuum of cavity
preparation based on size and instrumentation.
Air abrasion uses a stream of puried aluminum oxide particles
(27 to 50 µm) that are forced under pressure (40 to 120 psi)
through a ne-focused nozzle onto the tooth surface. is cuts
through enamel and dentin quickly, and it can also abrade or
roughen a tooth surface.
6
Originally introduced into dentistry by
R. Black in 1945,
7
air abrasion virtually disappeared from the
dental environment by the early 1960s and was reintroduced in
the early 1990s. Air abrasion oers some advantages over conven-
tional handpieces. ere is an absence of vibration and noise, caries
excavation can often be done without the need for local anesthesia,
and tooth preparation can be very fast. It is best suited for use
with adhesive restorations that require minimal tooth preparation
and less rigid classic cavity design than does amalgam. e cost
of the air abrasion unit ($2000 to $5000), the dust that can be

306 Part 3 The Primary Dentition Years: Three to Six Years
Figure 22.3 Note the difference in enamel thickness. The enamel of
the primary molars is approximately half the thickness of the enamel of
the rst permanent molars. Also note the interproximal caries requiring
restoration on the distal surface of the mandibular rst primary molar and
between the maxillary rst and second primary molars.
1. Primary teeth have thinner enamel and dentin thickness than permanent
teeth (see Fig. 22.3).
2. The pulps of primary teeth are larger in relation to crown size than
permanent pulps.
3. The pulp horns of primary teeth are closer to the outer surface of the tooth
than permanent pulps. The mesiobuccal pulp horn is the most prominent.
4. Primary teeth demonstrate greater constriction of the crown and have a
more prominent cervical contour than permanent teeth.
5. Primary teeth have broad, at proximal contact areas.
6. Primary teeth are whiter than their permanent successors.
7. Primary teeth have relatively narrow occlusal surfaces in comparison with
their permanent successors.
Anatomic Dierences Between Primary
and Permanent Teeth
BOX 22.1
used include the following: (1) in the presence of some xed
orthodontic appliances; (2) when a very recently erupted tooth
will not retain a clamp; and (3) in a child with an upper respiratory
infection, congested nasal passage, or other nasal obstruction.
However, even poor nasal breathers may tolerate the rubber dam
if a small (2- to 3-cm) hole is cut in the dam in an area away from
the operative quadrant. is allows for some mouth breathing.
Preparing for Placement of the Rubber Dam
e rubber dam is available in an assortment of colors and may
even be scented or avored. Virtually all rubber dams are made
of latex, although a latex-free rubber dam material is available
(Hygienic Corporation, Akron, OH) for use in latex-sensitive
patients. A 5 × 5-inch medium-gauge rubber dam is best suited
for use in children. Rubber dams are available in which a disposable
rubber dam frame is manufactured already attached to the dam
(Handidam, Aseptico, Woodinville, WA), eliminating the need
for a separate dam frame. e darker the dam, the better the
contrast between the teeth and dam. e holes should be punched
so that the rubber dam is centered horizontally on the face and
the upper lip is covered by the upper border of the dam, but the
dam does not cover the nostrils. One method of proper hole
placement is seen in Fig. 22.4A and B.
Punch the minimal number of holes necessary for good isolation
of all teeth to be restored. For single class I or V restorations, only
the tooth being restored may be isolated. If interproximal lesions
are being restored, at least one tooth anterior and one tooth posterior
to the tooth being restored should be isolated. is allows better
access, more ease in placing a matrix, and visualization of adjacent
marginal ridges for appropriate carving of the restoration.
When isolating several teeth, instead of punching numerous
holes in the dam, some clinicians will simply punch two holes
approximately one-half inch apart and cut the rubber dam with
scissors connecting the two holes. is is called the “slit technique
and allows for very quick placement of the rubber dam. Because
there is no rubber dam material interproximally, moisture control
is not as dependable with this placement technique, but it is often
still adequate, especially for isolation of maxillary quadrants.
Proper clamp selection is one of the most critical aspects of
good rubber dam application. Box 22.3 lists the most frequently
used clamps and their areas of utilization. Incisors usually require
ligation with dental oss for stabilization instead of a clamp.
After selecting an appropriate clamp, place a 12- to 18-inch
piece of dental oss on the bow of the clamp as a safety measure
(Fig. 22.5). is is necessary for easy retrieval of the clamp if it is
dislodged from the tooth and falls into the posterior pharyngeal
area.
Before trying the clamp on the tooth, oss the contacts through
which the rubber dam will be taken. If oss cannot be passed
through the contact because of defective restorations or other factors,
modication of the contacts or rubber dam will be necessary before
placement. Next, using the rubber dam forceps, place the clamp on
the tooth, seating it from a lingual to buccal direction. Be certain
that the jaws of the clamp are placed below the height of contour
and are not impinging on the gingival tissues. After seating the
clamp, remove the forceps and place a nger on the buccal and
lingual jaws of the clamp and apply gingival pressure to ensure that
the clamp is stable and has been seated as far gingivally as possible.
Placement of the Rubber Dam
e punched rubber dam should be lightly stretched onto the
rubber dam frame prior to placement of the clamp. is holds
Isolation in Pediatric Restorative Dentistry
Rubber Dam
e use of the rubber dam is indispensable in pediatric restorative
dentistry. Numerous advantages have been listed for its use, all
allowing for provision of the highest quality of care (Box 22.2).
Most pediatric restorative procedures can be completed with the
rubber dam in place. e few situations in which it may not be
1. Better access and visualization are gained by retracting soft tissues and
providing a dark contrasting background to the teeth.
2. Moisture control is superior to other forms of isolation.
3. The safety of the child is improved by preventing aspiration or swallowing
of foreign bodies and by protecting the soft tissues.
4. Placement generally results in decreased operating time.
5. Many children tend to become quieter and relaxed with a rubber dam in
place. The dam seems to act as a separating barrier, so that movements in
and out of the oral cavity are perceived by the child as being less invasive
than without the dam in place.
6. With a rubber dam in place, a child becomes primarily a nasal breather.
This enhances nitrous oxide administration when it has been deemed
necessary from a behavioral standpoint.
Advantages of Rubber Dam Use BOX 22.2

You're Reading a Preview

Become a DentistryKey membership for Full access and enjoy Unlimited articles

Become membership

If you are a member. Log in here

Was this article helpful?

CHAPTER 21 Dental Materials 301 and an increase in wear. To compensate for polymerization shrinkage, some of the Bis-GMA resin in the composite is prepolymerized by the manufacturer.More highly lled (>70% by volume) microlled resin–based composites are available and can be eectively used in areas where greater wear and stress is anticipated.Macrolled Resin–Based CompositeMacrolled resin–based composite (Fig. 2.12B) has silane-treated ller particles (approximately 80% by volume) in a Bis-GMA resin. e particle sizes are much larger than those found in microlled systems. Although these particles are larger than those found in the microlled composites, they are smaller than the conventional resin-based composite particles. e high ller-particle percentage increases wear resistance. Because most of these resin composites are used for posterior restorations, the material is usually radiopaque from the ller type.Hybrid Resin–Based CompositeHybrid resin–based composites (Fig. 21.12C) have a combination of small and large particles, representing the size of the particles found in microlled and macrolled resin–based composites, respectively. The high percentage of filler particles provides strength and wear resistance, yet the smaller ller particles allow for particles to arrange in close proximity to each other, which can provide minimal polymerization shrinkage and improved polishability compared with macrolled composite. ese resin-based composites are considered for restorations that may have stress-bearing areas during mastication but must have a well-polished surface.Nanolled Resin–Based CompositeSince the introduction of resin-based composites, the size of filler particles has become smaller. More recently, nanofilled composites (Fig. 21.12D) that contain very small ller particles have been introduced. ese resin composites oer the strength of a highly lled resin as well as polishability due to the small particles.Glass IonomerAnterior RestorationsPreparations of glass ionomer cements are available in various shades that can be used for anterior restorations.64,65 e use of glass ionomer for anterior restorations is limited to class III and class V preparations. e low fracture resistance and strength of mechanical bonding to enamel make its use impractical for class IV restorations. Retention of glass ionomer restorations in the restoration of class V preparations, where the gingival margin is not in enamel, may demonstrate favorable retention when restored with a glass ionomer rather than a resin-based composite. The fluoride release from glass ionomer restora-tions has been shown to inhibit the development of secondary caries.66–69Posterior Restorationse major disadvantage of glass ionomer cement as a posterior restorative material is its susceptibility to fracture and wear. Metal particles have been added to glass ionomer cement to increase their strength and wear resistance for posterior restorations. Fracture resistance remains a concern, and critical decisions should be made when using the material for posterior restorations. Investigations have demonstrated the clinical success of resin-modied glass ionomer cement as a posterior restorative material in the primary dentition.66,70,71 Again, uoride release and bonding capabilities are advantages of the glass ionomer cements.CompomersCompomers are recommended for use as a pediatric dental restorative material.72–75 Compomers are actually a cross between resin-based composite and glass ionomer cement.e compomers were developed in the hope of bringing the favorable properties of resin-based composite—such as wear resistance, color stability, and polishability—to the glass ionomers. An acid-base reaction takes place within the compomer material but is not the primary setting reaction; therefore visible light–polymerization is necessary to complete the setting reaction. Compomers are used with methacrylate primers that bond to enamel, dentin, and the compomer restorative material; therefore manufacturers consider the etching of tooth structure before restora-tion placement optional.CementsCements are frequently used in pediatric dentistry. eir primary use is for the cementation of stainless steel crowns and orthodontic bands. Zinc oxide–eugenol and glass ionomer are the cements most commonly used. ese cements were previously discussed in the section “Bases and Liners.” e particles in glass ionomer cement are usually larger than those found in glass ionomer bases. ere is less particle surface area available for reaction in the cement; therefore the cement sets more slowly than the base, allowing more working time. e importance of accuracy in the liquid/powder ratio of glass ionomer cement has been discussed. Encapsulated, premeasured cement is available and may be considered for clinical use. Automix syringe tips are available for the resin-modied glass ionomer materials as well.Bioactive cements have more recently become available in the marketplace. ese cements have glass particles incorporated into a resin matrix and have the advantage of bonding to tooth structure. e cements release calcium and uoride. Manufacturers recommend these cements for cementing stainless steel, porcelain, and zirconia crowns.e various cements most commonly used in pediatric dentistry and their clinical considerations are noted in Tables 21.1 and 21.2.Monolithic ZirconiaMonolithic zirconia was introduced to dentistry almost two decades ago; more recently, it has been used for complete coverage crowns. e zirconia ceramic crown is very strong in exural and compressive strength.76 A highly polished, glossy surface is very favorable to gingival tissue.76 Monolithic zirconia crowns are now available for the esthetic restoration of primary anterior and posterior teeth. An in vitro study has demonstrated that natural teeth opposing zirconia crowns have a more favorable wear than natural teeth opposing porcelain crowns.77 Currently, manufacturers recommend the use of resin-modied glass ionomer cement for zirconia, including bioactive cements (Bio Cem, NuSmile, Houston, TX; Ceramir, Doxa Dental Inc., Chicago, IL; Activa Bio Active Cement, Pulpdent Corporation, Watertown, MA). 302 Part 3 The Primary Dentition Years: Three to Six Years19. Swift EJ. Dentin/enamel adhesives: review of the literature. Pediatr Dent. 2002;24:456–461.20. Fuks A. e use of amalgam in pediatric dentistry. Pediatr Dent. 2002;24:448–455.21. Osborne JW, Summitt JB, Roberts HW. e use of dental amalgam in pediatric dentistry: review of the literature. Pediatr Dent. 2002;24:439–447.22. Osborne JW. ree-year clinical performance of eight amalgam alloys. Am J Dent. 1990;3:157–159.23. Council on Dental Materials and Devices. Revised American Dental Association Specication No. 1 for Alloy for Dental Amalgam. J Am Dent Assoc. 1977;95:614–617.24. Burgess JO, Walker R, Davidson BS. Posterior resin-based composite: review of the literature. Pediatr Dent. 2002;24:465–479.25. Donly KJ, Garcia-Godoy F. e use of resin-based composite in children. Pediatr Dent. 2002;24:480–488.26. Bowen RL. Dental lling material comprising vinyl-silane treated fused silica and a binder consisting of the reaction product of bisphenol and glycidyl methacrylate; 1962. U.S. Patent #3066112A.27. Phillips RW, Swartz ML, Norman RD. Materials for the Practicing Dentist. St Louis: Mosby; 1969:182–191.28. Bayne SC, Taylor DF, Sturdevant JR, et al. Protection theory for composite wear based on 5-year clinical results. J Dent Res. 1988;67 (Abstract 60):120.29. Ruyter IE. Polymerization and conversion in composite resins. In: Taylor DF, ed. Proceedings of the International Symposium on Posterior Composite Resins (Chapel Hill, NC, October 1982). Chapel Hill, NC: University of North Carolina; 1984:255–286.30. Asmussen E. Composite restorative resins. Composition versus wall to wall polymerization contraction. Acta Odontol Scand. 1975;33:337–344.31. Bowen RL, Rapson JE, Dickson G. Hardening shrinkage and hygro-scopic expansion of composite resins. J Dent Res. 1982;61:654–658.32. Donly KJ, Jensen ME. Posterior composite polymerization shrinkage in primary teeth: an in vitro comparison of three techniques. Pediatr Dent. 1986;8:209–212.33. Eick DJ, Welch FH. Polymerization shrinkage of composite resins and its possible inuence on postoperative sensitivity. Quintessence Int. 1986;77:103–111.34. Jorgensen KD, Asmussen E, Shimokobe H. Enamel damage caused by contracting restorative resins. Scand J Dent Res. 1975;83:120–122.35. Segura A, Donly KJ. Posterior composite polymerization shrinkage recovery following hygroscopic expansion. J Oral Rehabil. 1993;20:495–499.References1. Donly KJ, Wild TW, Jensen ME. Posterior composite class II restorations: in vitro comparison of preparation designs and restoration techniques. Dent Mater. 1990;6:88–93.2. Pereira JC, Mano AP, Franco EB, et al. Clinical evaluation of Dycal under amalgam restorations. Am J Dent. 1990;3:67–70.3. Straon LH, Corpron RL, Bruner FW, et al. Twenty-four-month clinical trial of visible-light activated cavity liner in young permanent teeth. J Dent Child. 1991;58:124–128.4. Manders CA, Garcia-Godoy F, Barnwell GM. Eect of a copal varnish, ZOE or glass ionomer cement bases on microleakage of amalgam restorations. Am J Dent. 1990;3:63–66.5. Heys RJ, Fitzgerald M. Microleakage of three cement bases. J Dent Res. 1991;70:55–58.6. Donly KJ, Ingram C. An in vitro caries inhibition of photopolymerized glass ionomer liners. ASDC J Dent Child. 1997;64:128–130.7. Garcia-Godoy F, Jensen ME. Articial recurrent caries in glass ionomer–lined amalgam restorations. Am J Dent. 1990;3:89–93.8. Hicks MJ, Flaitz CM, Silverstone LM. Secondary caries forma-tion in vitro around glass ionomer restoration. Quintessence Int. 1986;17:527–532.9. Jensen ME, Wefel JS, Hammesfahr PD. Fluoride-releasing liners: in vitro recurrent caries. Gen Dent. 1991;39:12–17.10. Diaz-Arnold AM, Holmes DC, Wistrom DW, et al. Short-term uoride release/uptake of glass ionomer restoratives. Dent Mater. 1995;11:96–101.11. Forsten L. Fluoride release and uptake by glass ionomers and related materials and its clinical eect. Biomaterials. 1998;19:503–508.12. Forsten L. Resin-modied glass ionomer cements: uoride release and uptake. Acta Odontol Scand. 1995;53:222–225.13. Skartveit L, Tveit AB, Tøtdal B, et al. In vivo uoride uptake in enamel and dentin from uoride-containing materials. ASDC J Dent Child. 1990;58:97–100.14. Donly KJ. Enamel and dentin demineralization inhibition of uoride-releasing materials. Am J Dent. 1994;7:275–278.15. Grin F, Donly KJ, Erickson RC. Caries inhibition of three uoride-releasing liners. Am J Dent. 1992;5:293–295.16. Mitra SB. Property comparisons of a light-cure and a self-cure glass ionomer liner. J Dent Res. 1989;68A(Abstract 740):274.17. Erickson RL. Mechanism and clinical implications of bond formation for two dentin bonding agents. Am J Dent. 1989;2:117–123.18. Garcia-Godoy F, Donly KJ. Dentin/enamel adhesives in pediatric dentistry. Pediatr Dent. 2002;24:462–464.Cement CompositionWorking Time Setting TimeCompressive StrengthBond Strength to DentinRelease of FluoridePulpal ResponseRemoval of ExcessIdeal — Medium Short-medium Very high High Yes None EasyGlass ionomer Silicate glass containing Ca, Al, FPolycarboxylic acidShort-medium Short High Medium Yes Low ModerateBioactive — High Medium High High Yes None ModerateZinc oxide and eugenolZinc oxideEugenolLong Medium Low-medium None No None EasyReinforced zinc oxide and eugenolZinc oxide reinforced with alumina or polymer eugenolLong Medium-long Low-medium None No None EasyModied from Farah JW, Powers JM. Cements. Dent Advisor. 1985;2(1):3.Comparison of Dental CementsTABLE 21.2 CHAPTER 21 Dental Materials 303 57. Phillips RW, Lutz F. Status reports on posterior composites. Council on Dental Materials, Instruments, and Equipment. J Am Dent Assoc. 1983;107:74–76.58. Derkson GD, Richardson AS, Waldman RJ. Clinical evaluation of composite resin and amalgam posterior restorations: two year results. J Can Dent Assoc. 1983;4:277–279.59. Ripa LW. Sealants revisited: an update of the eectiveness of pit-and-ssure sealants. Caries Res. 1993;27(suppl 1):77–82.60. Simonsen RJ. Retention and eectiveness of dental sealants after fteen years. J Am Dent Assoc. 1991;122:34–42.61. Wright JT, Crall JJ, Fontana M, et al. Evidence based clinical practice guideline for the use of pit and ssure sealants: a report of the American Dental Association and the American Academy of Pediatric Dentistry. J Am Dent Assoc. 2016;147(8):672–682.62. Hicks MJ, Flaitz CM. Caries-like lesion formation around uoride-releasing sealant and glass ionomer. Am J Dent. 1992;5:329–334.63. Jensen ME, Wefel JS, Triolo PT, et al. Eect of a uoride-releasing ssure sealant on articial enamel caries. Am J Dent. 1990;3:75–78.64. Berg JH. Glass ionomer cements. Pediatr Dent. 2002;24:430–438.65. Croll TP, Nicholson JW. Glass ionomer cements in pediatric dentistry: review of the literature. Pediatr Dent. 2002;24:423–429.66. Donly KJ, Segura A, Kanellis M, et al. Clinical performance and caries inhibition of resin-modied glass ionomer cement and amalgam restorations. J Am Dent Assoc. 1999;130:1459–1466.67. Ewoldsen H, Herwig L. Decay-inhibiting restorative materials: past and present. Compend Contin Educ Dent. 1998;19:981–992.68. Souto M, Donly KJ. Caries inhibition of glass ionomers. Am J Dent. 1994;7:122–124.69. ten Cate JM, van Duinen RN. Hypermineralization of dentinal lesions adjacent to glass-ionomer cement restorations. J Dent Res. 1995;74:1266–1271.70. Croll TP, Bar Zion Y, Segura A, et al. Clinical performance of resin-modied glass ionomer cement restorations in primary teeth: a retrospective evaluation. J Am Dent Assoc. 2001;132:1110–1116.71. Mjör IA, Dahl JE, Moorhead JE. Placement and replacement of restorations in primary teeth. Acta Odontol Scand. 2002;60:25–28.72. Hickel R. Glass ionomer, cements, hybrid-ionomers and compomers. Long term clinical evaluation. Trans Acad Dent Mater. 1996;9:105–112.73. Marks LA, Weerheijm KL, van Amerongen WE, et al. Dyract versus Tytin class II restorations in primary molars: 36 months evaluation. Caries Res. 1999;33:387–392.74. Peters MCRB, Roeters FJM. Clinical performance of a new compomer restorative in pediatric dentistry. J Dent Res. 1994;73A(Abstract 34): 106.75. Roeters JJ, Frankenmolen F, Burgersdijk RC, et al. Clinical evaluation of Dyract in primary molars: 3-year results. Am J Dent. 1998;11:143–148.76. Malkondu Ö, Tinastepe N, Akan E, et al. An overview of mono-lithic zirconia in dentistry. Biotechnol Biotechnol Equip. 2016;30: 644–652.77. Jung YS, Lee JW, Choi YJ, et al. A study on the in-vitro wear of the natural tooth structure by opposing zirconia on dental porcelain. J Adv Prosthodont. 2010;2:111–115.36. Craig RG. Chemistry, composition and properties of composite resins. Dent Clin North Am. 1981;25:219–239.37. Ruyter IE. Monomer systems and polymerization. In: Vanherle C, Smith DC, eds. Posterior Composite Resin Dental Restorative Materials. Utrecht, Netherlands: Peter Szulc; 1985:109–135.38. Smith DC. Posterior composite dental restorative material: materials development. In: Vanherle G, Smith DC, eds. Posterior Composite Resin Dental Restorative Materials. Utrecht, Netherlands: Peter Szulc; 1985:47–60.39. Z250. Material Safety Data Sheet. St Paul, MN: 3M ESPE.40. Weinmann W, alacker C, Guggenberger R. Siloranes in dental composites. Dent Mater. 2005;21:68–74.41. Van Dijken JWV, Lindberg A. Clinical eectiveness of a low shrinkage composite. A ve-year study. J Adhes Dent. 2009;11:143–148.42. Pilo R, Oelgiesser D, Cardash HS. A survey of output intensity and potential for depth of cure among light-curing units in clinical use. J Dent. 1999;27:235–241.43. Flury S, Hayoz S, Peutzfeldt A, et al. Depth of cure of resin composites. Is the ISO 4049 method suitable for bulk-ll materials? Dent Mater. 2012;28:521–528.44. El-Safty S, Silikas N, Watts DC. Creep deformation of restorative resin-composites intended for bulk-ll placement. Dent Mater. 2012;28:928–935.45. Burgess J, Cakir D. Comparative properties of low-shrinkage composite resins. Compend Contin Educ Dent. 2010;31:10–15.46. Ilie N, Hickel R. Investigations on a methacrylate-based owable composite based on the SDR technology. Dent Mater. 2011;27:348–355.47. Czasch P, Ilie N. In vitro comparison of mechanical properties and degree of cure of bulk-fill composites. Clin Oral Investig. 2013;17:227–235.48. Peutzfeldt A. Resin composites in dentistry: the monomer systems. Eur J Oral Sci. 1997;105:97–116.49. Moszner N, Fischer UK, Angermann J, et al. A partially aromatic urethane as a new substitute for Bis-GMA in restorative composites. Dent Mater. 2008;24:694–699.50. Giachetti L, Bertini F, Bambi C, et al. A rational use of dental materials in posterior direct resin restorations in order to control polymerization shrinkage stress. Minerva Stomatol. 2007;56:129–138.51. Eames WB, Strain JD, Weitman RT, et al. Clinical comparison of composite, amalgam, and silicate restorative materials. J Am Dent Assoc. 1974;89:1111–1117.52. Leinfelder KF, Sluder TB, Santos JF, et al. Five-year clinical evaluation of anterior and posterior restorations of composite resin. Oper Dent. 1980;5(2):57–65.53. Osborne JW, Gale EN, Ferguson GW. One-year and two-year clinical evaluation of composite resin vs. amalgam. J Prosthet Dent. 1973;30:795–800.54. Phillips RW. Observations on a composite resin for class II restorations: two-year report. J Prosthet Dent. 1972;28:164–169.55. Leinfelder KF, Roberson TM. Clinical evaluation of posterior composite resins. Gen Dent. 1983;31:276–280.56. Jaarda MJ, Wang RF, Lang BR. A regression analysis of ller particle content to predict composite wear. J Prosthet Dent. 1997;77:57–67. 304 22 Restorative Dentistry for the Primary DentitionWILLIAM F. WAGGONER AND TRAVIS NELSONCHAPTER OUTLINEInstrumentation and Caries RemovalAnatomic Considerations of Primary TeethIsolation in Pediatric Restorative DentistryRubber DamAlternative Isolation SystemsRestoration of Primary MolarsAdhesive Materials in Primary MolarsAmalgam Use in Primary MolarsGeneral Principles for Intracoronal Restoration of Primary Posterior TeethRestoration of Primary Incisors and CaninesClass III Adhesive RestorationsClass V Restorations for Incisors and CaninesFull Coronal Coverage of IncisorsProsthetic Replacement of Primary Anterior Teethtooth structure, uoride release, improved esthetics, reduction of mercury exposure, and conservation of tooth structure. None of the esthetic materials have the track record and proven durability of amalgam or stainless steel, but when they are placed appropriately, they can provide useful restorations for the lifespan of the primary tooth. is chapter will provide information on both the new and the traditional restorative techniques. For the interested reader, in 2014 the American Academy of Pediatric Dentistry sponsored a Pediatric Dentistry Restorative Symposium Conference. The published proceedings2 include extensive and up-to-date literature reviews and discussion of pediatric restorative techniques at a greater depth than can be included in this chapter. In addition, a more detailed discussion of dental materials used in pediatric restorative dentistry can be found in Chapter 21.Instrumentation and Caries RemovalNearly all instrumentation for restorative procedures is carried out with the high-speed handpiece (100,000 to 300,000 rpm, either electric or air turbine) combined with coolant. e coolant may be water spray or air alone. A water spray coolant is often recom-mended for high-speed instrumentation; however, there is some evidence that air coolant alone may be used without creating irreversible pulpal damage,3,4 and use of both coolant techniques is taught in many pediatric dental residency programs.5 ere are some instances when a water spray coolant is absolutely necessary. is is especially true when removing old amalgam restorations or using diamond burs. Regardless of the coolant used, intermittent cutting at intervals of a few seconds with light, brushing strokes should be done to prevent excessive heat generation. Protective masks and eyewear should always be worn when using the high-speed air turbine handpiece.e low-speed handpiece (500 to 15,000 rpm) is most frequently used primarily for caries removal and occasionally for polishing and nishing procedures. As with high-speed instrumentation, light pressure and brushing strokes should be used when using the low-speed handpiece. Use of hand instrumentation is minimal in most operative preparations in the primary dentition and is usually limited to nal caries removal.Although use of a handpiece for caries removal and cavity preparation is by far the most popular and frequently used method, there are at least three other methods of treating carious teeth. ese are air abrasion, laser treatment, and chemomechanical methods. With these methods, tooth preparations move from the Pediatric restorative dentistry is a dynamic combination of ever-improving materials and tried-and-true techniques. Many aspects of primary teeth restoration have not changed for decades. In 1924 G.V. Black outlined several steps for the prepara-tion of carious permanent teeth to receive an amalgam restoration.1 ese steps have been adopted, with slight modication, for the restoration of primary teeth. Restorative techniques for the primary dentition using amalgam and stainless steel crowns (SSCs) have remained relatively consistent for decades (Fig. 22.1). However, with an increased use of adhesive restorative materials and bonding systems, there has been a shift to more conservative preparations and restorations. Materials such as glass ionomers, resin ionomer products, and improved resin-based composite systems have been developed that are having a profound impact on the restoration of primary teeth. In addition, premilled zirconia crowns (ZCs) now oer an esthetic alternative to SSCs. Unfortunately, long-term clinical data (i.e., longer than 3 years) regarding many of these newer materials are limited; but even so, many clinicians are successfully using these materials with increasing frequency.e clinician can stay with the proven, successful materials of the past, such as amalgam and stainless steel, or move to newer, more esthetic materials that oer advantages such as bonding to CHAPTER 22 Restorative Dentistry for the Primary Dentition 305 ADBC• Figure 22.1 Traditionally restored primary dentition demonstrating stainless steel crown (A), preveneered steel crowns (B), class III amalgam (C), and class II amalgam (D). Note: All white, esthetic alternatives now exist for each of these restorations. ConventionalG.V. Black MicrodentistryExtensionforpreventionTooth substance saving preparationsDrill and fillAnesthesiaG.V. BlackPreventionofextensionFilling without drillingLaser/Air abrasionChemomechanicalcaries removalNo (less) anesthesiaMicrodentistryPit andfissurepreparationsBox-onlypreparationsAdhesivecavities• Figure 22.2 Cavity preparation continuum. (Courtesy Dr. Luc Martens, Ghent, Belgium.)generated during the procedure, and the fact that it does not completely eliminate the need for conventional handpieces are three disadvantages of the system that seem to keep it from gaining widespread use. Laser techniques have also become popular with some dental operators. Lasers can be used in children for soft tissue surgery, caries prevention, caries diagnosis, biostimulation and pain control, hemostasis during pulpotomy procedures, and cavity preparation.8 An erbium:YAG laser can be used in restorative dentistry for minimally invasive preparation of pits and ssures and hypoplastic teeth, cavity preparation of all classes (I thorough V), treatment of deep dentinal caries, and laser-assisted pulp capping. Some of the advantages of using lasers for cavity preparation include (1) better patient acceptance because they are quiet, (2) no vibration and minimal need for use of anesthetic, (3) minimally invasive cavity preparation because of the selective absorption of laser light by carious tissue, (4) production of very clean cavity preparations free of a smear layer, (5) minimal thermal increase in the pulp chamber, and (6) the production of cavity preparations with a macroroughened surface that increases surface bonding area for better adhesion of resin-based materials. Some disadvantages include (1) a longer learning curve; (2) higher equipment costs ($30,000 to $60,000 for an erbium:YAG laser); (3) need for specialized training; and (4) possible need for a traditional handpiece to complete the process, depending on the cavity size and preparation needed.9 Chemomechanical caries removal is a noninvasive technique that eliminates infected dentin via a chemical agent by means of dissolution. Instead of drilling, a chemical agent such as Carisolv (MediTeam AB, Göteberg, Sweden) or Papacarie (F&A Laboratorio Farmaceutico Ltd., São Paulo, Brazil) is applied to the carious dentin and assisted by hand instruments to remove soft carious material. is method usually does not require anesthesia, it preserves sound tooth structure, and it relies on bonded restorative materials for nal restoration. Drawbacks to this method include an increase in operator time to remove caries, only certain carious lesions are suitable for its use, a handpiece may still be necessary to gain access to the dentinal or interproximal areas, and few long-term data are available to conrm long-term success of the method.10One nal aspect to be considered when discussing tooth prepara-tion is the use of magnication during operative procedures. Up until the 1990s the use of magnication for dental procedures by most practitioners came only with increasing age and failing eyesight, but now the use of magnifying loupes or microscopes for most dental procedures is taught from the beginning of most dental school training. Loupes are available in a wide range of magnica-tion, but generally a set of loupes with a 2.5× to 3.5× magnication is recommended for restorative dentistry. e use of magnication for completing restorative procedures has several advantages, such as an increase in productivity, an increase in the level of excellence and condence in dental treatment, an increase in visual diagnostic abilities, and perhaps most importantly, improvement in operator posture and comfort to help prevent musculoskeletal disorders brought about by poor operator positioning.11 Use of magnication during cavity preparation has not yet become the standard of care, but it is highly recommended and will likely become the standard of care in the next few years.Anatomic Considerations of Primary TeethAlthough some primary teeth resemble their permanent successors, they are not miniature permanent teeth. Several anatomic dierences must be distinguished before restorative procedures are begun (Box 22.1; Fig. 22.3).traditional, conventional preparations used by G.V. Black to much more conservative, “tooth-saving” preparations, known as micro-dentistry or minimally invasive dentistry. Depending on the type of carious lesions, method of instrumentation, and restorative material to be used, the clinician can opt for a conventional G.V. Black type of cavity preparation or for a much more conservative micropreparation. Fig. 22.2 illustrates a continuum of cavity preparation based on size and instrumentation.Air abrasion uses a stream of puried aluminum oxide particles (27 to 50 µm) that are forced under pressure (40 to 120 psi) through a ne-focused nozzle onto the tooth surface. is cuts through enamel and dentin quickly, and it can also abrade or roughen a tooth surface.6 Originally introduced into dentistry by R. Black in 1945,7 air abrasion virtually disappeared from the dental environment by the early 1960s and was reintroduced in the early 1990s. Air abrasion oers some advantages over conven-tional handpieces. ere is an absence of vibration and noise, caries excavation can often be done without the need for local anesthesia, and tooth preparation can be very fast. It is best suited for use with adhesive restorations that require minimal tooth preparation and less rigid classic cavity design than does amalgam. e cost of the air abrasion unit ($2000 to $5000), the dust that can be 306 Part 3 The Primary Dentition Years: Three to Six Years• Figure 22.3 Note the difference in enamel thickness. The enamel of the primary molars is approximately half the thickness of the enamel of the rst permanent molars. Also note the interproximal caries requiring restoration on the distal surface of the mandibular rst primary molar and between the maxillary rst and second primary molars. 1. Primary teeth have thinner enamel and dentin thickness than permanent teeth (see Fig. 22.3).2. The pulps of primary teeth are larger in relation to crown size than permanent pulps.3. The pulp horns of primary teeth are closer to the outer surface of the tooth than permanent pulps. The mesiobuccal pulp horn is the most prominent.4. Primary teeth demonstrate greater constriction of the crown and have a more prominent cervical contour than permanent teeth.5. Primary teeth have broad, at proximal contact areas.6. Primary teeth are whiter than their permanent successors.7. Primary teeth have relatively narrow occlusal surfaces in comparison with their permanent successors.Anatomic Dierences Between Primary and Permanent Teeth• BOX 22.1 used include the following: (1) in the presence of some xed orthodontic appliances; (2) when a very recently erupted tooth will not retain a clamp; and (3) in a child with an upper respiratory infection, congested nasal passage, or other nasal obstruction. However, even poor nasal breathers may tolerate the rubber dam if a small (2- to 3-cm) hole is cut in the dam in an area away from the operative quadrant. is allows for some mouth breathing.Preparing for Placement of the Rubber Dame rubber dam is available in an assortment of colors and may even be scented or avored. Virtually all rubber dams are made of latex, although a latex-free rubber dam material is available (Hygienic Corporation, Akron, OH) for use in latex-sensitive patients. A 5 × 5-inch medium-gauge rubber dam is best suited for use in children. Rubber dams are available in which a disposable rubber dam frame is manufactured already attached to the dam (Handidam, Aseptico, Woodinville, WA), eliminating the need for a separate dam frame. e darker the dam, the better the contrast between the teeth and dam. e holes should be punched so that the rubber dam is centered horizontally on the face and the upper lip is covered by the upper border of the dam, but the dam does not cover the nostrils. One method of proper hole placement is seen in Fig. 22.4A and B.Punch the minimal number of holes necessary for good isolation of all teeth to be restored. For single class I or V restorations, only the tooth being restored may be isolated. If interproximal lesions are being restored, at least one tooth anterior and one tooth posterior to the tooth being restored should be isolated. is allows better access, more ease in placing a matrix, and visualization of adjacent marginal ridges for appropriate carving of the restoration.When isolating several teeth, instead of punching numerous holes in the dam, some clinicians will simply punch two holes approximately one-half inch apart and cut the rubber dam with scissors connecting the two holes. is is called the “slit technique” and allows for very quick placement of the rubber dam. Because there is no rubber dam material interproximally, moisture control is not as dependable with this placement technique, but it is often still adequate, especially for isolation of maxillary quadrants.Proper clamp selection is one of the most critical aspects of good rubber dam application. Box 22.3 lists the most frequently used clamps and their areas of utilization. Incisors usually require ligation with dental oss for stabilization instead of a clamp.After selecting an appropriate clamp, place a 12- to 18-inch piece of dental oss on the bow of the clamp as a safety measure (Fig. 22.5). is is necessary for easy retrieval of the clamp if it is dislodged from the tooth and falls into the posterior pharyngeal area.Before trying the clamp on the tooth, oss the contacts through which the rubber dam will be taken. If oss cannot be passed through the contact because of defective restorations or other factors, modication of the contacts or rubber dam will be necessary before placement. Next, using the rubber dam forceps, place the clamp on the tooth, seating it from a lingual to buccal direction. Be certain that the jaws of the clamp are placed below the height of contour and are not impinging on the gingival tissues. After seating the clamp, remove the forceps and place a nger on the buccal and lingual jaws of the clamp and apply gingival pressure to ensure that the clamp is stable and has been seated as far gingivally as possible.Placement of the Rubber Dame punched rubber dam should be lightly stretched onto the rubber dam frame prior to placement of the clamp. is holds Isolation in Pediatric Restorative DentistryRubber Dame use of the rubber dam is indispensable in pediatric restorative dentistry. Numerous advantages have been listed for its use, all allowing for provision of the highest quality of care (Box 22.2). Most pediatric restorative procedures can be completed with the rubber dam in place. e few situations in which it may not be 1. Better access and visualization are gained by retracting soft tissues and providing a dark contrasting background to the teeth.2. Moisture control is superior to other forms of isolation.3. The safety of the child is improved by preventing aspiration or swallowing of foreign bodies and by protecting the soft tissues.4. Placement generally results in decreased operating time.5. Many children tend to become quieter and relaxed with a rubber dam in place. The dam seems to act as a separating barrier, so that movements in and out of the oral cavity are perceived by the child as being less invasive than without the dam in place.6. With a rubber dam in place, a child becomes primarily a nasal breather. This enhances nitrous oxide administration when it has been deemed necessary from a behavioral standpoint.Advantages of Rubber Dam Use• BOX 22.2 CHAPTER 22 Restorative Dentistry for the Primary Dentition 307 • Figure 22.5 A oss safety through the bow of the rubber dam clamp allows for easy retrieval of the clamp, should it become dislodged from the tooth. (Modied from The DAE Project. Instructional Materials for the Dental Health Professions: Rubber Dam. New York: Teachers College Press, Teachers College, Columbia University; 1982:66.)the mouth widely and consider placement of a mouth prop. With the index ngers, stretch the most posterior hole of the rubber dam over the bow and wings of the clamp. Sometimes when isolating the most posterior maxillary molars, the bow of the clamp rests very close to the anterior border of the ramus when the mouth is opened wide. is makes slipping the dam material over the bow dicult, but when one simply asks the child to close the mouth slightly, the ramus will move posteriorly and allow the material to slide between the bow and the ramus.If necessary, adjust the tension of the rubber dam on the frame. Next, stabilize the rubber dam around the most anterior tooth. is may be done by placing a wooden wedge interproximally, by stretching a small piece of rubber dam through the contact, or by ligating with dental oss. To ligate, place oss (12 to 18 inches) around the cervix of the tooth and have the dental assistant hold the oss gingivally on the lingual with a blunt instrument. Draw the oss tightly around the tooth from the buccal and tie a surgical knot below the cervical bulge. Do not cut the ends of the ligature tie, because the long ends remind the operator that the ligature is present. After anterior stabilization, all other teeth can be isolated for which holes have been punched. A blunt hand instrument can be used to invert the rubber dam into the gingival sulcus around each isolated tooth.Removing the Rubber DamTo remove the rubber dam when restorative procedures are complete, rst rinse away all debris and cut and remove any ligatures used for stabilization. Next, stretch the rubber dam so that the dam’s interproximal septa may be cut with a pair of scissors. e clamp, frame, and dam are then removed as a unit with the rubber dam forceps. Inspect the dam and the mouth to see that no small pieces of dam material have been left interproximally. Gently massage the tissue around the previously clamped tooth, and rinse and evacuate the oral cavity.the corners of the dam out of the line of the operator’s vision during placement. If the material is stretched too tightly, tension is too great and the clamp may be dislodged when the material is stretched over the bow of the clamp. Next, pull the oss attached to the clamp through the most posterior hole in the dam that has been punched for the clamped tooth. Instruct the child to open Primary canine13BA4521st primary molar2nd primary molar1st permanent molar1/2"• Figure 22.4 Preparation of the rubber dam. (A) The Young frame is applied to the rubber dam. The upper limit of the frame coincides with the upper edge of the rubber dam material. The dam is divided vertically into thirds, and the area inside the frame is divided in half horizontally. The holes for each tooth are placed as indicated, at a 45-degree angle 3 to 4 mm apart. (B) The rubber dam punch table with corresponding teeth and hole sizes. ([B] Modied from The DAE Project. Instructional Materials for the Dental Health Professions: Rubber Dam. New York: Teachers College Press, Teachers College, Columbia University; 1982:42.)aIvory, Heraeus-Kulzer, South Bend, IN.bHygienic Corp., Akron, OH.cHu-Friedy Mfg. Co., Chicago, IL.“A” clamps have jaws angled gingivally to seat below subgingival heights of contour.Partially erupted permanent molars: 14A, 8Aa,b,cFully erupted permanent molars: 14, 8b,cSecond primary molars: 26, 27,c 3a,bFirst primary molars/bicuspids/permanent canines: 2, 2A,a,b 207, 208cPrimary incisors and canines: 0,a 00,b 209cCommon Rubber Dam Clamps for Pediatric Restorative Dentistry• BOX 22.3 308 Part 3 The Primary Dentition Years: Three to Six YearsStep 3: Place the cheek shield into the buccal vestibule. Move the isthmus onto the retromolar pad behind the maxillary tuberosity. Adjust the tongue retractor in the lingual vestibule as needed. Move the bite block distally to provide more vertical working room.Behavioral Considerations When Using Alternative Isolation SystemsWhen used properly, both rubber dam and alternative isolation systems can provide good moisture control and protection of oral soft tissues. Although placement of rubber dams typically requires administration of local anesthetic, alternative isolation systems do not. is may lead users to believe that the alternative system is better tolerated by patients than are rubber dams. is observation may be especially true for sealants and other situations in which local anesthetic would not otherwise be used. However, for operative dentistry, local anesthetic is generally used. erefore, when local anesthetic is applied, a rubber dam is perceived to be relatively comfortable and often presents as a less bulky isolation technique. In addition, compared with cotton roll isolation, research indicates that rubber dams may decrease stress when used with children. In Alternative Isolation SystemsIn recent years, novel isolation systems have been introduced to dentistry. ese systems incorporate high-volume evacuation, a bite block, and protective barriers for the tongue and cheek. Some systems are made of transparent materials. is increases visibility and allows incorporation of illumination into the mouthpiece (Isolite, Isolite Systems, Santa Barbara, CA; Fig. 22.6). The mouthpieces are constructed of exible polymer materials that are several millimeters thick but easily adapt to the mouth’s contours and provide protection of the soft tissues. ese systems reduce moisture and average oral humidity to levels that are similar to a rubber dam. As an added benet, the design allows the operator to simultaneously work on opposing maxillary and mandibular quadrants. ese systems also exhibit continuous evacuation, which may reduce the start/stop time required with the use of high-volume evacuators (HVEs) in four-handed dentistry. A comparison of alternative isolation systems with the rubber dam is found in Table 22.1.Manufacturers produce mouthpieces in a variety of sizes to accommodate most patients. Two popular systems, Isolite and DryShield (DryShield, Fountain Valley, CA), require purchase of specic armamentarium for each dental unit that is equipped. Other systems such as Mr. irsty (Zirc, Bualo, MN) connect directly to existing HVEs. Mouthpieces may be disposable (Isolite, Mr. irsty) or autoclavable and reusable (DryShield).Placement of Alternative Isolation SystemsStep 1: Hold the control head with index nger and thumb. With your other hand, fold the cheek shield onto the tongue retractor. Gently slide the folded mouthpiece into the buccal vestibule on the side to receive treatment. Angle the mouthpiece to allow the lower edge of the tongue retractor to move along the buccal edge of the teeth.Step 2: Move the bite block onto the occlusal surface of the teeth, just distal to the mandibular cuspid. Instruct the patient to “rest gently” on the bite block to secure.• Figure 22.6 Isolite-alternate isolation system. (Courtesy Isolite Systems, Santa Barbara, CA. Used with permission.)Rubber DamAlternative Isolation Systems(Isolite, DryShield, Mr. Thirsty)IsolationMoisture control + +Reduction of aerosol + +Improves visibility of eld + +Continuous evacuation +Protection from debris and dropped instruments++ +Retracts gingival tissues +Ability to isolate partially erupted teeth+ ++Saves time + ++Illumination + (Isolite only)BehavioralReduces mouth breathing, may increase N2O inhalation+Reduces talking ++ +Added noise −Challenge in sizing for some children/gagging−Local anesthesia required −ImplementationCost for disposable supplies Very low ModerateCost for armamentarium Low HighContrasting the Rubber Dam With Alternative Isolation SystemsTABLE 22.1 CHAPTER 22 Restorative Dentistry for the Primary Dentition 309 risk of secondary caries in composite restorations is signicantly greater than for amalgam, but amalgam is more prone to fracture than composites.20,21 Another 5-year longitudinal study showed similar results, with no statistically signicant dierence in overall failure rate between composite and amalgam; however, composite restorations required seven times more repairs than amalgam.17 e ADA’s Council on Scientic Aairs has concluded that when used correctly in the primary and permanent dentition, the expected lifetimes of resin-based composites can be comparable to that of amalgam in class I, II, and V restorations.22 It should be noted that these conclusions were based upon using the three-step etch, prime, and bond systems, and self-etching bond systems may not oer the same results.e use of resin-based composite materials in primary molars oers the advantages of improved esthetics, elimination of mercury, low thermal conductivity, more conservation of tooth structure, easier reparability, and bonding of the restorative material to the tooth. Disadvantages include an exacting technique, incompatibility with moisture contamination during placement, increased operator time, potential marginal leakage, possible postoperative sensitivity, and a tendency for loose or open contacts.23–25 e ADA has approved several resin-based composites for use in posterior teeth.In addition to resin-based composites, polyacid-modied resin-based composites, also known as compomers (Dyract eXtra [Dentsply Sirona, York, PA]), RMGIs (Vitremer and Ketac Nano [3M ESPE, St. Paul, MN]), and glass ionomers (Ketac Fil Plus [3M ESPE]), have all been suggested and studied for use in primary molar restorations. Several clinical studies have evaluated compomer use in primary molars26–31 and likewise found them to provide useful, predictable restorations. RMGI cement has also been evaluated in several clinical studies.32–34 It seems that these restora-tions demonstrate more color change and occlusal wear than resin-based composites or compomers but still function well in class I, II, III, and V restorations. Glass ionomer cements have also been used in restoring primary molars but with less satisfactory results than the other adhesive materials.34,35 Use of glass ionomers for multisurface or large restorations in primary molars, except for teeth with a very limited lifespan, is generally not recommended or indicated.Amalgam Use in Primary MolarsAlthough use of adhesive restorative materials continues to rise, amalgam remains the restorative material of choice for many clini-cians. Favorable handling properties, good longevity, and less technique sensitivity make this material a good option for restoration of primary posterior teeth. However, it should be noted that concerns have been raised about exposure of dentists, patients, and the environment to mercury in amalgam. is has led to the use of amalgam for cavity restoration to be banned in several European countries. Current scientic information continues to support the use of amalgam as a restorative material,36 but for a more detailed discussion of the controversy the reader is referred to Chapter 21.General Principles for Intracoronal Restoration of Primary Posterior TeethClass I RestorationsAmalgam Preparation Designe classic G.V. Black outline form is the basis for both adhesive and amalgam class I preparations. For amalgam, it includes all contrast, a signicant percentage of children expressed that they felt that the alternative isolation system mouthpiece stretched their mouth and made them feel as if they were going to gag. e eects on patient behavior of alternative isolation systems have not been well studied. Other factors to consider include greater noise when using alternative systems and the fact that rubber dams facilitate nose breathing, which can enhance the eect of nitrous oxide inhalation sedation.Restoration of Primary Molarse anatomy of the primary molars, with their ssured occlusal surfaces and broad, at interproximal contact areas, makes them the most caries-susceptible primary teeth. e importance of primary molars in mastication and as maintainers of space for the succedane-ous teeth, coupled with the development of suitable economic restorative materials, has shaped a philosophy of restoring and conserving primary molars, versus extraction or supervision of caries.SSCs, ZCs, amalgam, and adhesive materials such as resin-based composites, resin-modied glass ionomers (RMGIs), polyacid-modied resin-based composites (compomers), and glass ionomers are the materials used in the restoration of primary molars. Although amalgam was historically the material of choice for intracoronal restorations, the use of adhesive materials for restoring posterior teeth continues to increase annually. It is estimated that more than 50% of intracoronal restorations placed are resin-based composites. Following is a discussion of primary molar restoration which has been divided topically based upon the number of tooth surfaces treated, with specic focus on dierences encountered with dierent restorative materials.Adhesive Materials in Primary MolarsAs early as the mid-1960s, composite resins (now referred to as resin-based composites) were suggested as esthetic replacements for class I and class II amalgam restorations in molars. Initial results were promising, but clinical failures of the resin restorations began to occur after approximately 2 years, with the greatest problem being occlusal wear.12 However, further improvements in resin-based composite materials, such as smaller ller particles, increases in material strength, and improvement of dentin-bonding agents, have led to improved clinical results. Currently there are still minimal long-term clinical data available on longevity of resin-based composite materials in primary teeth. However, there are several studies in teeth that demonstrate good performance over time.13–17 For example, in a 5-year study comparing posterior composites and amalgams, Norman and colleagues18 reported satisfactory results for both amalgam and composite. e only signicant statistical dierences were a poorer marginal integrity for the amalgam and a greater wear rate for the resin. However, the wear rate for the composite was well within the acceptable limits established by the American Dental Association (ADA) Council on Dental Materials. Roberts and associates also found no signicant dierence in clinical performance or wear of class II amalgam and resin-based composites restorations evaluated for 3 years.19 Bernardo and colleagues, in a 7-year clinical study comparing amalgam and resin-based composite, found composite to be an acceptable restorative material.20 However, amalgam demonstrated fewer failures than resin-based composites, particularly in restorations with three or more surfaces. In the Bernardo et al. study, recurrent decay was the main cause of failure of the posterior composite restorations. Evidence suggests that the 310 Part 3 The Primary Dentition Years: Three to Six Yearsof smoothly owing arcs and curves, and all internal angles should be rounded slightly. When a dovetail is placed in the second primary molars, its buccolingual width should be greater than the width of the isthmus to produce a locking form to provide resistance against occlusal torque, which may displace the restoration mesially or distally. e isthmus should be one-third of the intercuspal width, and the buccolingual walls should converge slightly in an occlusal direction. e mesial and distal walls should are at the marginal ridge so as not to undercut ridges. Oblique ridges should not be crossed unless they are undermined with caries or are deeply ssured. Primary mandibular second molars often exhibit buccal developmental pits. When carious, these should be restored with a small teardrop- or ovoid-shaped restoration, including all the adjacent susceptible pits and ssures. e steps of preparation and restoration of class I amalgam restorations are listed in Box 22.4.Adhesive Restoration Preparation DesignIn large part, class I adhesive restorations follow the same preparation principles as amalgam restorations. However, adhesive materials adhere to noncarious pits and ssures and can be placed successfully in shallower preparations. erefore the preparation design for adhesive materials is typically more conservative and may incorporate elements of restorative and sealant techniques. is is referred to as a conservative adhesive restoration (CAR).Conservative Adhesive Restorations for Primary Teeth. CAR is an updated term given to a restoration technique rst described by Simonsen and Stallard in 197737 and rened in 198538 as preven-tive resin restoration (PRR). is restoration combines the preventive approach of sealing susceptible pits and ssures with conservative class I cavity preparation of caries occurring on the same occlusal surface. Instead of the traditional amalgam cavity preparation’s “extension for prevention” beyond the area of decay into the adjacent pits and ssures, the CAR or PRR limits cavity preparation to the discrete areas of decay. ese preparations are lled with an adhesive material, usually resin-based composite or compomer, and then the entire occlusal surface is sealed. is results in a restoration that conserves tooth structure and is both therapeutic and preventive. Note that “preventive resin restoration” is the nomenclature that CBA• Figure 22.7 G.V. Black class I amalgam cavity preparations. (A) Maxil-lary right second and rst primary molars (occlusal view). (B) Maxillary second primary molar, lingual view of distolingual groove preparation. (C) Mandibular right rst and second primary molars (occlusal view). 1. Administer appropriate anesthesia and place the rubber dam.2. Using a no. 330 bur in the high-speed turbine handpiece, penetrate the tooth parallel to its long axis in the central pit region and extend into all susceptible ssures and pits to a depth 0.5 mm in dentin.3. Remove all carious dentin. Use a large, round bur in the slow-speed handpiece or a sharp spoon excavator.4. Smooth the enamel walls and rene the nal outline form with the no. 330 bur.5. Rinse and dry the preparation, and inspect for (1) caries removal, (2) sharp cavosurface margins, and (3) removal of all unsupported enamel.6. Triturate the amalgam, and place one carrier load of amalgam into the preparation.7. Using a small condenser, immediately begin condensation of the amalgam into the preparation, condensing small overlapping increments with a rm pressure until the cavity is slightly overlled.8. Following condensation, use a ball burnisher to begin the initial contouring of the amalgam by pushing the excess amalgam up and away from the margins. Then carving of most alloys can begin almost immediately. A small cleoid-discoid carver works very well for carving primary restorations. Always keep part of the carving edge of the instrument on the tooth structure so that overcarving of the cavosurface margin does not occur. Remove all amalgam ash from cavosurface margins. Keep the carved anatomy shallow. Placing deep anatomy in primary teeth (i.e., grooves) can weaken the restoration by creating a thin shelf of amalgam at the cavosurface margin and also by reducing the bulk of amalgam in the central stress-bearing areas, both leading to fracture.9. When the amalgam has begun its initial set and resists deformation, begin to burnish the amalgam. Burnishing is done with a small, round burnisher, which is lightly rubbed across the carved amalgam surface to produce a satin-like appearance. Besides smoothing, burnishing creates a substructure with fewer voids and reduces nishing time.10. A wet cotton pellet can be wiped across the burnished amalgam for a nal smoothing (optional).11. Remove the rubber dam, and check the occlusion. Children must be cautioned before the rubber dam is completely removed that they must not close their teeth into occlusion until instructed to do so. With articulating paper, check the restoration for occlusal irregularities, instructing the child to close gently. Make necessary adjustments with the carver.12. Rinse the oral cavity and massage the soft tissue around the previously clamped tooth.Steps of Preparation and Restoration of Class I Amalgam Restorations• BOX 22.4 retentive ssures and carious areas but is as conservative as possible (Fig. 22.7).Ideal pulpal oor depth is 0.5 mm into dentin (approximately 1.5 mm from the enamel surface). e length of the cutting end of the no. 330 bur is 1.5 mm, so this becomes a good tool for gauging cavity depth. e cavosurface margin should be placed out of stress-bearing areas and should have no bevel. To help prevent stress concentration, the outline form should be composed CHAPTER 22 Restorative Dentistry for the Primary Dentition 311 anesthesia because of the minimal tooth preparation; however, soft tissue anesthesia may be necessary for comfort in placing the rubber dam.Table 22.2 describes the dierences between the two types of restorative materials.Common Errors With Class I RestorationsSome frequent errors made in class I restorations are (1) preparing the cavity too deep; (2) undercutting the marginal ridges (particularly critical for amalgam); (3) carving the anatomy too deep; (4) not removing amalgam ash from cavosurface margins; (5) undercarving/undercontouring, which leads to subsequent fracture or tooth sensitivity from hyperocclusion; and (6) not including or sealing all susceptible ssures. Note that for amalgam an alternative to including all the susceptible ssures is to conne the amalgam preparation to the area of decay and seal the rest of the tooth with a pit and ssure sealant. Sealing over restorative materials signi-cantly decreases microleakage41 and increases the longevity of the restoration.42,43Liners and Bases in Primary TeethNeither liners nor bases are very widely used in primary teeth, but various bases and liners are discussed in Chapter 21. in liners such as calcium hydroxide do not provide thermal insulation, and recent evidence suggests that calcium hydroxide may hydrolyze gradually,44 leaving a small void underneath the restoration and ultimately weakening it.45 erefore use of calcium hydroxide is discouraged. Placement of bases in primary teeth is also uncommon, but when necessary, use of a glass ionomer or an RMGI material is recommended.Class II RestorationsGeneral Considerationse outline form for several class II amalgam preparations is shown in Fig. 22.9. As with class I restorations, amalgam requires a larger and more specic form than adhesive materials. To prepare the ABCDESSCRBA• Figure 22.8 (A) The occlusal surface of a mandibular second primary molar with a small, discrete area of decay in the central pit. (B) A small bur (no. 14 or 12 round or Fissurotomy) is used to remove the decay, which is conned to the enamel. (C) A lled sealant (S) is applied into the preparation and over all susceptible pits and ssures. This is considered a sealant procedure. (D) In this diagram, the caries extends into the dentin. Again, a small round bur is used to conservatively remove the decay. (E) A bonding agent (BA) and resin-based composite (CR) material are placed in the preparation. Then a sealant (S) is applied over all the remaining susceptible pits and ssures. Adhesive Restorations AmalgamTechnique Highly technique sensitive Less technique sensitiveIsolation Critical ImportantPreparation designMaterial properties allow for smaller, shallower preparationsMaterial properties require larger, more aggressive preparationsNoncarious pits and ssuresNoncarious pits and ssures can simply be sealedNoncarious pits are included in preparation design for classic amalgamsContemporary techniques incorporate sealing over noncarious pitsRetention Minor mechanical retention is prudent, as less enamel exists in primary teeth for bondingMechanical retention must be incorporated into preparation designSummary of Dierences in Restorative MaterialsTABLE 22.2 has been historically used; however, this terminology has been replaced by “conservative adhesive restoration” to reect the fact that other adhesive materials, besides resins, may be used in these restorations. CAR will be the term used to describe this technique in this chapter.e CAR is ideally suited for minimal carious lesions in teeth that would otherwise lose a considerable amount of tooth structure if the extension for prevention treatment were followed.39 Houpt and colleagues40 reported 79% retention of CARs in permanent molars after 9 years and concluded that the CAR was a successful conservative alternative to treatment of minimal occlusal caries. Although long-term retention studies of CARs in primary teeth are lacking, with retention rates of CARs and sealants in permanent teeth being very similar, it is not unreasonable to believe that retention rates of CARs in primary teeth would also be similar to sealant rates.Teeth that are suitable for CARs are those that demonstrate small, discrete regions of decay, often limited to a single pit (Fig. 22.8). As with sealants, the ability to isolate the tooth and keep it dry throughout the procedure is the single most important indication. Amalgam or RMGIs, being less sensitive to tech-nique and moisture, would be the restorative materials of choice if the tooth cannot be kept dry. Many CARs do not require 312 Part 3 The Primary Dentition Years: Three to Six YearsLevering48 reported that SSCs placed in 4-year-old and younger children showed a success rate approximately twice that of class II amalgams, for each year up to 10 years of service. Roberts and Sherri49 reported that after 5 years, one-third of class II amalgams placed in primary teeth had failed or required replacement, whereas only 8% of SSCs required retreatment. In the preschool child with large proximal carious lesions, SSCs are preferred to amalgams because of their durability. Similar-sized lesions in teeth that are within 2 or 3 years of exfoliation may be restored with amalgam because the anticipated lifespan is fairly short.Adhesive Restoration Preparation Design. e steps in prepara-tion and restoration of a primary or permanent molar with composite resin are very similar to those followed for restoration with amalgam but with a few alterations. For resin-based composites, absolute moisture control is a must, making a rubber dam almost mandatory. Tooth preparations for class II resin-based composites have undergone a tremendous evolution over the years, with many peculiar shapes and designs suggested. Unlike amalgam preparations, which have been well dened for years, there is no current consensus about the precise design of a class II preparation for a primary molar to receive an adhesive material. A 2001 survey of pediatric dentistry departments in North American dental schools found that 57% of the dental schools teach a conservative “box-only” preparation (with and without retention grooves), whereas 36% use and teach the traditional G.V. Black amalgam preparation.50 Leinfelder51 recommended that a class II preparation be primarily restricted to the region of the caries, with little to no occlusal extensions. He also states that extending the proximal box line angles in “self-cleansing” areas is not necessary and in fact creates a larger restoration that is more prone to occlusal wear. In recent years, dentin-bonding agents and adhesive restorative materials have improved dramatically, suggesting that under the right cir-cumstances the slot preparation (Fig. 22.10) may be used eec-tively.26,52–54 Although evidence indicates that the technique can be successful, experience suggests that a conservative preparation that incorporates mechanical retention such as a small dovetail or a cavosurface margin bevel55 to increase surface area for bonding should improve retention and overall success of the restoration. Beveling not only increases the surface area to be etched but also removes the aprismatic layer of enamel which may not etch well and may leave islands of unetched enamel that can act as pathways for bacterial leakage and/or reduce resin bond strength to the enamel.13Matrix ApplicationMatrices are placed for interproximal restorations to aid in restoring normal contour and contact areas and to prevent extrusion of restorative materials into gingival tissues. Many types of matrix bands are available for use in pediatric dentistry. Regardless of the type of matrix band used, after it is in place and a wedge rmly inserted, a small ball burnisher can be used to burnish the band in the area of the contact point against the adjacent tooth. is will help provide a tight proximal contact.1. T band: allows for multiple matrices; no special equipment is needed.2. Sectional matrices (e.g., Strip-T, Denovo Dental, Inc., Baldwin Park, CA; Palodent Plus Sectional Matrices, Dentsply Sirona): allow for multiple matrix placement, are very easy to use, are not circumferential, must be held in place by a wedge.3. AutoMatrix (Dentsply Sirona): allows for multiple matrix placement, is very easy to use, requires special tightening and removal tools.class II restoration, the guidelines given for the class I preparation should be followed during the preparation of the occlusal portion. Preparation of the proximal surface requires additional steps during both preparation and restoration. Placement of an interproximal wedge prior to and during preparation is highly desirable to achieve a slight separation of teeth and consequently a tighter interproximal contact of the final restoration. The wedge also protects the interproximal gingival tissue during instrumentation and thereby reduces the likelihood of hemorrhage into the proximal box during instrumentation.Amalgam Restoration Preparation Design. For the class II amalgam, the proximal box should be broader at the cervical portion than at the occlusal portion. e buccal, lingual, and gingival walls should all break contact with the adjacent tooth, just enough to allow the tip of an explorer to pass. e buccal and lingual walls should create a 90-degree angle with the enamel. e gingival wall should be at, not beveled, and all unsupported enamel should be removed. Ideally, the axial wall of the proximal box should be 0.5 mm into dentin and should follow the same contour as the outer proximal contour of the tooth. Because occlusal forces may permit a concentration of stress within the amalgam around sharp angles, the axiopulpal line angle is routinely beveled or rounded. No buccal or lingual retentive grooves should be placed in the proximal box. e mesiodistal width of the gingival seat should be 1 mm, which is approximately equal to the width of a no. 330 bur.In primary teeth, many practitioners limit class II amalgam restorations to relatively small two-surface restorations. ree-surface (MOD) restorations may be done, but studies have shown that SSCs are a more durable and predictable restoration for large multiple surface restorations in primary teeth.46,47 Messer and CBA• Figure 22.9 G.V. Black class II amalgam cavity preparations. (A) Maxil-lary right second and rst primary molars (occlusal view). (B) Mandibular second primary molar (proximal view); note occlusal convergence of proxi-mal walls. (C) Mandibular right rst and second primary molars (occlusal view). CHAPTER 22 Restorative Dentistry for the Primary Dentition 313 ere are many commercially available sectional matrices or “matrix pieces.” One commonly used in pediatrics is the Strip-T matrix. ey are stainless steel matrix strips approximately one-half inch long that do not encircle the prepared tooth but rather t only in the prepared proximal area. For small class II preparations, they are very simple to place and use. After placement, they must be rmly wedged to stay in place. ey are not recommended for proximal preparations that extend beyond the line angles; a cir-cumferential matrix (or SSC) is more appropriate in that instance.AutoMatrix is a preformed loop of stainless steel matrix material that is placed on the tooth (Fig. 22.12) and tightened with a special tightening tool that comes with the kit. A small pin automati-cally keeps the tightened matrix tightly bound around the tooth. To remove the matrix, this small pin is clipped (another special tool) and the matrix is easily loosened and removed.Placement of Restorative Materials in Class II RestorationsAmalgam. e steps of preparation and restoration of class II amalgam restorations are listed in Box 22.5.Retention grooveRetention grooveShort bevelShort bevelABC• Figure 22.10 Modied class II cavity preparations for adhesive restor-ative materials. Note the short bevel around the preparations and small retention groves. (A) Maxillary right second and rst primary molars (occlu-sal view). (B) Mandibular second primary molar (proximal view); note occlusal convergence of proximal walls. (C) Mandibular right rst and second primary molars (occlusal view). CBA• Figure 22.11 (A) The T-band matrix. (B) The T band is formed into a circle, and the extension wings are folded down to secure the band. (C) The T band is adapted to t the tooth tightly and is trimmed with scissors, and the free end is bent back. • Figure 22.12 A sectional matrix (Strip-T, Denovo) is placed onto a mesioocclusal preparation of the second primary molar. An AutoMatrix (Dentsply Sirona) is seen placed on the distoocclusal preparation of the rst primary molar. The matrix can be tightened to draw the band more closely to the tooth. A wedge secures both in place. 4. Toemire matrix: is used infrequently because it does not t primary tooth contour well and is dicult to place as multiple matrices.T bands are available in dierent sizes, contours, and materials. A straight, narrow, brass T band will work in almost all pediatric restorative procedures. e T-band matrix (Fig. 22.11) is formed by folding the band back on itself in the form of a circle and by folding over the extension wings of the “T” to make an adjustable loop. e band is contoured and positioned onto the tooth with the folded extension wings on the buccal surface. e free end of the band is drawn mesially to pull the band snugly against the tooth. e extension folds are then grasped rmly with a pair of Howe no. 110 pliers and removed from the tooth. e band should then be tightened an additional 0.5 to 1.0 mm, and the free end should be bent back over the vertical folds and cut with scissors to a length of 5 to 6 mm. e band is then reseated onto the tooth and wedged. It must t below the gingival margin of the preparation and must also be at least 1 mm higher than the marginal ridge of the adjacent tooth. e T band is removed by opening the extension wings with an explorer or spoon excavator and allowing the band to open. Scissors are then used to cut one end of the band close to the restored proximal surface, the wedge is removed, and the band is then drawn buccally or lingually through the contact. 314 Part 3 The Primary Dentition Years: Three to Six Years1. Administer appropriate anesthesia, and place the rubber dam.2. Place a wooden wedge in the interproximal area being restored (optional). This retracts the gingival papilla during instrumentation, keeps the operator from cutting the interseptal rubber dam material and underlying gingiva, and creates some prewedging, which helps to ensure a tight proximal contact of the nal restoration.3. Using a no. 330 bur in the high-speed turbine handpiece with a light, brushing motion, prepare the occlusal outline form at ideal depth.4. To prepare the proximal box, begin at the marginal ridge by brushing the bur buccolingually in a pendulum motion and in a gingival direction at the dentin-enamel junction. Continue until contact is just broken between the adjacent tooth and the gingival wall and the wedge is seen. If the gingival wall is made too deep, the cervical constriction of the primary molar will create a very narrow gingival seat. The widest buccolingual width of the box will be at the gingival margin. Take care not to damage the adjacent proximal surface.5. Remove any remaining caries with a sharp spoon excavator or with a round bur in the low-speed handpiece.6. Round the axiopulpal line angle slightly. Because of the shape of the no. 330 bur, all other internal line angles will automatically be gently rounded.7. Remove the wedge placed at the beginning of the treatment and place a matrix band.8. While holding the matrix band in place, forcefully reinsert the wedge between the matrix band and the adjacent tooth, beneath the gingival seat of the preparation. The wedge is placed with a pair of Howe pliers or cotton forceps from the widest embrasure. The wedge should hold the band tightly against the tooth but should not push the band into the proximal box. It may be necessary to trim the wedge slightly to achieve a proper t.9. Triturate the amalgam. With the amalgam carrier, add the amalgam to the preparation in single increments, beginning in the proximal box.10. Using a small condenser, condense the amalgam into the corners of the proximal box and against the matrix band to ensure the reestablishment of a tight proximal contact. Continue lling and condensing until the entire cavity is overlled.11. Use a small round burnisher to begin the initial contouring of the amalgam. Carving of the occlusal portion is performed with a small cleoid-discoid carver, as in class I restorations. The marginal ridge can be carved with the tip of an explorer or with a Hollenback carver.12. Carefully remove the wedge and the matrix band. Drawing the band in a buccal-lingual direction, as opposed to an occlusal direction, will be less likely to damage the marginal ridge of the newly placed restoration during withdrawal.13. Remove excess amalgam at the buccal, lingual, and gingival margins with an explorer or Hollenback carver. Check to see that the height of the newly restored marginal ridge is approximately equal to the adjacent marginal ridge.14. Gently oss the interproximal contact to check the tightness of the contact, to check for gingival overhang, and to remove any loose amalgam particles from the interproximal region.15. Do a nal burnish of the restoration, and use a wet cotton pellet held with the cotton pliers for nal smoothing if necessary.16. Remove the rubber dam carefully.17. Check the occlusion for irregularities with articulating paper, and adjust as needed.Steps of Preparation and Restoration for Class II Amalgam Restorations• BOX 22.5 Adhesive Restorations. If an RMGI base or liner is to be used, it should be placed and cured before the etching or adhesive steps. For details regarding specics of adhesive systems, refer to Chapter 40. e preparation should be etched for 15 to 20 seconds with an acid gel. e etchant should extend well beyond the cavosurface margin to cover any susceptible pits and ssures not included in the preparation. After thoroughly rinsing the etch from the tooth, a dentin-bonding agent is applied and cured. Several self-etching bonding systems are now available that eliminate the separate etching and rinsing steps. However, not all self-etching systems can be used successfully in primary teeth, and clinical studies are lacking as to their eectiveness.13 Following application of the adhesive, many clinicians will place a owable resin-based composite as a cavity liner. Although not mandatory, it appears that use of a thin (0.5 to 1 mm) owable liner reduces the voids at the cervical cavosurface margin in class II restorations56 and may consequently reduce microleakage. e owable material may be cured before placement of the packable material, but best marginal sealing likely comes from placement of the packable composite over a thin, uncured owable liner.Many resin-based composites and compomers are prepackaged in small ampules that can be injected directly into the prepara-tion. A plastic instrument or a condenser can be used to pack or condense the composite into the preparation. No more than a 2- to 4-mm depth of composite should be polymerized at one time. ere is some debate about whether resin-based composites should be placed in bulk or incrementally. It appears that one of the primary concerns is that the curing light must penetrate to the full depth of the material. Limiting the depth of material placed to 2 to 4 mm per increment should ensure full polymerization. Incremental placement may also reduce polymerization shrinkage, a suspected cause of dentin-bonding agent failure and postoperative sensitivity. Complete curing or polymerization of the material is very important to the success of the restoration. Undercuring may lead to a weakened restoration prone to failure under masticatory forces. When placing the nal increment of packable resin, slightly overll the preparation with material and use a ball burnisher to push the material toward and up over the enamel margins. is will remove excess material and eectively act as a carver. Do not use a cleoid-discoid carver on resin-based composite material. Use the tip of the explorer to carve the marginal ridge away from the matrix band. Remember to always move the instrument from material to tooth, pushing the material toward the margins. If you move instruments from tooth to restoration, you will likely pull material away from the margins, leaving a gap. After nal cure of the restoration, remove the wedge and matrix band and cure the restoration one more time, directing the light toward the proximal from a buccal or lingual approach. Finishing can begin immediately following polymerization. e occlusal surface is grossly contoured with round, high-speed carbide nishing burs or ne-nishing diamond burs. Gross contouring of proximal surfaces is accomplished with ame-shaped, high-speed carbide nishing burs and with garnet disks, where accessible. Final nishing can be completed with a white stone or with rubber abrasive points to eliminate surface irregularities and nal polishing with a composite polish or gloss. Fine abrasive disks or strips are used for nal polishing of accessible proximal margins. e application of a surface sealant after polishing may serve to reduce occlusal wear and contraction gaps.57Adjacent or Back-to-Back Class II RestorationsAmalgam. Adjacent interproximal lesions are not uncommon in the primary dentition. From the standpoint of time and patient management, it is desirable to restore these lesions simultaneously. CHAPTER 22 Restorative Dentistry for the Primary Dentition 315 in the area where you want to create the contact point. en add, contour, and polymerize the resin-based composite material in the second preparation. Remove the wedge and bands, and nishing and polishing procedures are identical to single restoration placement.Common Problems With Class II RestorationsClass II restorations are prone to many of the errors discussed previously for class I restorations. In addition to these considerations, it is important to recognize that the proximal box of a class II preparation is a feature that can contribute to recurrent decay or restoration loss. Indeed, most restorative problems in pediatric dentistry result from a failure to prepare and restore the teeth in a way that considers their anatomic or morphologic structural characteristics (Fig. 22.14). Marginal failure in the proximal box, usually owing to an excessive are of the cavosurface margin, is a common issue with class II restorations. Failure to remove all caries during preparation and leaving material voids due to inadequate condensation also contribute to restoration failure.58,59 Failure of adhesive restorations may also result due to deviation from manufacturer recommendations for light cure time and maximum material depth.Finishing of Adhesive and Amalgam RestorationsFinishing and polishing of adhesive restorations is standard practice and is described in detail previously. On the other hand, polishing of amalgams is no longer routinely recommended. Historically, polishing of amalgams was advocated to (1) eliminate surface scratches and blemishes, which act as centers of corrosion, (2) remove any remaining amalgam ash not carved away, and (3) rene the anatomy and occlusion. However, good burnishing and carving during placement eliminates most of the need for polishing. Although there are no contraindications to amalgam polishing, there is little evidence that polishing amalgam restorations contributes to their clinical success or longevity; thus this procedure has generally fallen out of favor.Preparation for adjacent proximal restorations is identical to those previously described. A matrix is placed on each tooth and is properly wedged. T bands, sectional matrices, or automatrices are preferable because multiple matrix holders are dicult to place side by side. Condensation of the amalgam should be done in small increments, alternately in each preparation, so that the restorations are lled simultaneously (Fig. 22.13). Condensation pressure toward the matrix will help to ensure a tight interproximal contact. Carve the marginal ridges to an equal height, and carefully remove the wedge and matrix bands one at a time. Final carving is like that described for solitary class II restorations.Adhesive Restorations. Placement of adjacent back-to-back class II resin-based composite restorations is acceptable and encouraged when there are two adjacent carious lesions to be restored, but the method is dierent from that of placing back-to-back amalgam restorations. After the preparations are completed, matrix bands or segmental matrices are placed on both preparations and a wedge is forcefully inserted between the two bands. Be certain that the place-ment of the matrices allows a convexity to the proximal surface of both teeth. Sometimes the matrices are placed such that if the resin material were placed into the preps, one proximal surface would be vastly overcontoured and the adjacent surface vastly undercontoured. is will result in two poorly contoured restorations. is can be prevented by carefully placing the matrices and observing their contour before resin placement; or by putting the matrix on one tooth, restoring it completely, and then placing the matrix band on the second tooth and restoring it. However, it is possible to place both matrices and restore simultaneously. With two matrix bands in place, etch and bond both preparations. To avoid voids in the proximal box, put the tip of the composite ampule in the bottom of the box against the gingival oor and slowly back ll the box. Next completely ll, contour, and polymerize one of the restorations. To ensure a tight contact between the two restorations, after the rst restoration is polymerized, use a small ball burnisher and burnish the matrix band against the newly placed restoration AB• Figure 22.13 “Back-to-back” amalgam preparations. (A) After wedging, begin condensing the adjacent proximal boxes alternately. (B) Continue condensing the amalgams alternately until both preparations are slightly overlled. CBGFEDA• Figure 22.14 Common errors with class II amalgam cavity prepara-tions. (A) Failure to extend occlusal outline into all susceptible pits and ssures. (B) Failure to follow the outline of the cusps. (C) Isthmus cut too wide. (D) Flare of proximal walls too great. (E) Angle formed by the axial, buccal, and lingual walls too great. (F) Gingival contact with adjacent tooth not broken. (G) Axial wall not conforming to the proximal contour of the tooth, and the mesiodistal width of the gingival oor is greater than 1 mm. (Modied from Forrester DJ, Wagner M, Fleming J. Pediatric Dental Medi-cine. Philadelphia: Lea & Febiger; 1981.) 316 Part 3 The Primary Dentition Years: Three to Six Yearsposterior strip crowns (Space Maintainers Laboratory, Chatsworth, CA) and a preveneered molar crown which is an SSC with a composite veneer overlay on the buccal and occlusal surfaces (e.g., NuSmile Primary Crowns, Houston, TX; and Cheng Crowns, Exton, PA). Because of their infrequent use, they will not be discussed in chapter.SSCs are by far the most frequently used full coverage crown in the primary dentition, but the use of ZCs is increasing in popularity. e indications for use of both are listed in Box 22.6. e steps of preparation and placement of SSCs and ZCs are listed in Box 22.7 and are shown in Fig. 22.16.Special Considerations for Primary Crown Placement65Placement of Adjacent Crowns. When quadrant dentistry is practiced, it often is necessary to place SSCs or ZCs on adjacent teeth. e tooth preparation and crown selection for placing multiple crowns are similar to that previously described for single crowns. However, there are several areas of consideration as follows:• Prepareocclusal reductionof onetoothcompletely beforebeginning occlusal reduction of the other tooth. When reduction of two teeth is performed simultaneously, the tendency is to underreduce both.• Insucientproximalreductionisacommonproblemwhenadjacent crowns are placed. Contact between adjacent proximal surfaces should be broken, producing approximately 1.5-mm separation at the gingival level.• Bothcrownsshouldbetrimmed,contoured,andpreparedforcementation simultaneously. It is generally best to begin place-ment and cementation of the more distal tooth rst. However, most importantly, the sequence of placement of crowns for cementation should follow the same sequence as when the crowns were placed for nal tting. Sometimes crowns will seat quite easily in one placement sequence and will seat with great diculty if the sequence is altered.Preparing Crowns in Areas of Space Loss. Frequently, when the tooth structure is lost because of caries, a loss of contact and drifting of adjacent teeth into space normally occupied by the tooth to be restored occurs. When this happens, the crown required to t over the buccolingual dimension will be too wide mesiodistally to be placed and a crown selected to t the mesiodistal space will be too small in circumference. Placing ZCs in areas of space loss can be extremely challenging and may be a contraindication to their placement. is is because the ZCs cannot be reshaped and the only way to get them to t in areas of space loss is extensive Full Coronal Coverage of Primary MolarsPreformed metal crowns, also referred to as stainless steel crowns (SSCs), were introduced to pediatric dentistry by Humphrey in 1950.60 Since then, they have become an invaluable restor-ative material and treatment of choice for badly broken down primary teeth. As mentioned previously, they are generally considered superior to large, multisurface amalgam or adhesive restorations and have a longer clinical lifespan than two- or three-surface restorations.46–48,61,62 e crowns are manufactured in dierent sizes as a metal shell with some preformed anatomy and are trimmed and contoured as necessary to t individual teeth.ere are two commonly used types of SSCs:1. Precontoured crowns (e.g., 3M ESPE Stainless Steel Crowns, Minneapolis, MN; and Acero 3S crowns [Acero Crowns, Seattle, WA]): is type of crown is by far the most popular and their use is recommended. eir anatomy more closely resembles a natural tooth. ese crowns are prefestooned and precontoured. Some trimming and contouring may be necessary but usually is minimal. If trimming of these crowns becomes necessary, the precontour will be lost and the crown will t more loosely than before trimming.2. Pretrimmed crowns (e.g., Unitek stainless steel crowns [3M ESPE] and Denovo Crowns): ese crowns have straight, noncontoured sides but are festooned to follow a line parallel to the gingival crest. ey still require contouring and some trimming. ese are good crowns but require much more time and eort for placement and are not widely used.e biggest parental complaint about SSCs is their esthetics. Unfortunately, there are no tooth-colored, durable SSCs available; however, there are other esthetic full coverage options which have been gaining in popularity since 2010. One such option is a premade ZC for primary teeth (Fig. 22.15). ere is still not a lot of clinical information available about zirconia ceramic crowns for primary teeth; however, ZCs in adults have been shown to be very esthetic, durable, stain resistant, biocompatible, and retentive,63 so it is anticipated that their performance in children will be similar. Although zirconia is a very hard material, it appears that ZCs do not cause excessive wear on the enamel of opposing teeth.64 Like SSCs, these primary ZCs come in six premade sizes and can be prepared, t, and cemented in a 20- to 30-minute visit. eir indications and placement will be discussed later. Two other esthetic full coverage alternatives which are not widely used are resin-bonded BA• Figure 22.15 (A) A zirconia primary molar crown and a molar stainless steel crown. (B) Zirconia crowns on rst and second primary molars. CHAPTER 22 Restorative Dentistry for the Primary Dentition 317 1. Restoration of primary or young permanent teeth with extensive carious lesions. These include primary teeth with extensive decay, large lesions, or multiple surface lesions. First primary molars with mesial interproximal lesions are included in the category because the morphologic appearance that the tooth exhibits results in inadequate support for mesial interproximal restorations.2. Restoration of hypoplastic primary or permanent teeth.3. Restoration of primary teeth following pulpotomy or pulpectomy procedures.4. Restoration of teeth with hereditary anomalies such as dentinogenesis imperfecta or amelogenesis imperfecta.5. Restorations in disabled individuals or others in whom oral hygiene is extremely poor and failure of other materials is likely.6. As an abutment for space maintainers or prosthetic appliances (stainless steel crowns only, not zirconia).7. Strong consideration should be given to the use of full coverage restorations in children who require general anesthesia for dental treatment and demonstrate a high caries risk.Indications for Use of Full Coverage Primary Crowns• BOX 22.6 Data from Seale NS. The use of stainless steel crowns. Pediatr Dent. 2002;24(5):501–505.HALL TECHNIQUE OF STAINLESS STEEL CROWN PLACEMENTN. Sue SealeThe Hall technique (HT) of stainless steel crown (SSC) placement represents a remarkable change over the past 10 years in the use of SSCs. The technique, rst practiced in 1988 by N. Hall, a general practitioner in Scotland, used a novel technique where a crown was tted and cemented over a caries affected primary molar without local anesthetic (LA), caries removal, or tooth preparation.1,2 There have been a number of investigations, both retrospective and prospective, published about SSCs placed with the HT,2–5 and the authors all concluded that HT was a predictable restorative option with low retreatment rates.The technique is simple. On the day of crown placement, the child should be seated in the dental chair and kept in an upright position because no rubber dam is used and the airway must be protected. No LA is administered. The dentist chooses the smallest SSC that will seat over the unprepared tooth. It should cover all cusps with a feeling of “spring back,” and there should be no attempt to seat the crown during try-in. The chosen SSC is then lled with glass ionomer (GI) cement and seated over the caries affected primary molar, initially using nger pressure and then the child’s own occlusal force if necessary. Excess cement is removed, and occlusal pressure maintained by having the child bite on a cotton roll until the cement sets. Occlusion is allowed to adjust to the increased occlusovertical dimension over time. Because the HT of SSC placement requires no tooth preparation, occasionally orthodontic spacers are needed in the interproximal areas of the tooth to be crowned to create the spacing necessary to allow easy placement of the crown. The spacers are left in place for several days prior to the crown appointment.1,6The HT has been controversial since its introduction into the United States due to the initial open bite created by cementing the SSC over an unprepared tooth and because all caries-affected dentin is sealed in the tooth under the SSC. However, studies show the open bite resolved within the rst month,3,7 and sealing caries-affected dentin in teeth is much like an indirect pulp cap, which has abundant good evidence that it works so long as the seal is maintained and the pulpal status is properly diagnosed pretreatment.8,9 To that end, high-quality radiographs showing the furcation and a thorough clinical history for symptoms are mandatory in selecting teeth to receive the HT of SSC placement.Despite the controversy associated with the HT, there are denitely indications for its use in the United States. Young, uncooperative children who have open, active caries in their primary molars, but who have no funding for treatment in the operating room or who are placed on long wait lists to receive such treatment, can be treated on an interim basis with the HT. Newly erupting permanent molars with enamel hypoplasia and early destruction of the occlusal surfaces can be treated with the HT until the tooth erupts sufciently to receive a more denitive restoration. The HT of SSC placement can be used much as interim therapeutic restoration (ITR) with GI has been used in the past. It provides an interim approach for large lesions where the tooth is badly broken down, and IRT with GI would not have the strength to protect the tooth.As the HT receives increased use and more well-designed prospective studies evaluate its long-term effectiveness, there may be more acceptance of it, and more uses may become evident.References1. Innes N, Evans D, Hall N. The Hall technique for managing carious primary molars. Dent Update. 2009;36:472–478.2. Innes NP, Stirrups DR, Evans DJ, et al. A novel technique using preformed metal crowns for managing carious primary molars in general practice—a retrospective analysis. Brit Dent J. 2006;200:451–454.3. Innes NP, Evans DJ, Stirrups DR. The Hall technique: a randomized controlled clinical trial of a novel method of managing carious primary molars in general dental practice: acceptability of the technique and outcomes at 23 months. BMC Oral Health. 2007;7:18.4. Innes NP, Evans DJ, Stirrups DR. Sealing caries in primary molars: randomized control trial, 5-year results. J Dent Res. 2011;90: 1405–1410.5. Ludwig KH, Fontana M, Vinson LA, et al. The success of stainless steel crowns placed with the Hall technique: a retrospective study. J Am Dent Assoc. 2014;145:1248–1253.6. Hall Technique Guide, A Users Manual. Version 3, University of Dundee, Scotland.7. van der Zee V, van Amerongen WE. Inuence of preformed metal crowns (Hall technique) on the occlusal vertical dimension in the primary dentition. Eur Arch Paediatr Dent. 2010;11:225–227.8. Falster CA, Araujo FB, Straffon LH, et al. Indirect pulp treatment: in vivo outcomes of an adhesive resin system vs calcium hydroxide for protection of the dentin-pulp complex. Pediatr Dent. 2002;24:241–248.9. Ricketts DN, Lamont T, Innes NP, et al. Operative caries management in adults and children. Cochrane Database Syst Rev. 2013;(3):CD003808.circumferential tooth reduction. For SSCs a larger crown, which will t over the tooth’s greatest convexity, is selected and an adjustment is made to reduce mesiodistal width (Fig. 22.17). is adjustment is accomplished by grasping the marginal ridges of the crown with Howe utility pliers and squeezing it, thereby reducing the mesiodistal dimension. Considerable recontouring of proximal, buccal, and lingual walls of the crown with the no. 137 or no. 114 pliers will be necessary (Fig. 22.18). If diculty in crown placement is still encountered, additional tooth reduction of the buccal and lingual surfaces and selection of another, smaller crown may be necessary. When the area of space loss is in the region of the distal surface of a mandibular rst primary molar and diculty 318 Part 3 The Primary Dentition Years: Three to Six YearsSeveral different preparation designs have been advocated for stainless steel crowns (SSCs) over the years. Only one such preparation, requiring minimal tooth reduction for SSCs, is discussed here. Necessary adjustments for zirconia crown preparation, tting, and cementation are noted for each step.1. Evaluate the preoperative occlusion. Note the dental midline and the cusp-fossa relationship bilaterally.2. Administer appropriate local anesthesia, ensuring that all soft tissues surrounding the tooth to be crowned are well anesthetized, and place a rubber dam. Because gingival tissues all around the tooth may be manipulated during crown placement, it is important to obtain lingual or palatal, as well as buccal or facial anesthesia.3. Reduction of the occlusal surface is carried out with a no. 169L taper ssure bur or a football diamond in the high-speed handpiece. Make depth cuts by cutting the occlusal grooves to a depth of 1.0–1.5 mm, and extend through the buccal, lingual, and proximal surfaces. Next, place the bur on its side and uniformly reduce the remaining occlusal surface by 1.5 mm, maintaining the cuspal inclines of the crown (see Fig. 22.15). Establish access to decay with a no. 330 or 169L bur in the high-speed handpiece. Then remove decay with a large, round bur in the low-speed handpiece or with a spoon excavator. Note: If a zirconia crown is going to be placed, slightly more occlusal reduction (1.5–2 mm) will be necessary.4. Proximal reduction is also accomplished with the taper ssure bur or thin, tapered diamond. Contact with the adjacent tooth must be broken gingivally and buccolingually, maintaining vertical walls with only a slight convergence in an occlusal direction. Proximal reduction should be approximately 1 mm. The gingival proximal margin should have a feather-edge nish line. Care must be taken not to damage adjacent tooth structure. Note: For placement of a zirconia crown, proximal reduction should be at least 1.5 mm mesially and distally but also ending in a feather-edge.5. Round all line angles, using the side of the bur or diamond. The occlusobuccal and occlusolingual line angles are rounded by holding the bur at a 30- to 45-degree angle to the occlusal surface and sweeping it in a mesiodistal direction. For SSCs, buccolingual reduction is often limited to this beveling and is conned to the occlusal one-third of the crown. If problems are later encountered in selecting an appropriate crown size or in tting a crown over a large mesiobuccal bulge, more reduction of the buccal and lingual tooth structure may become necessary. Important Note: If a zirconia crown is being placed, circumferential reduction including the buccal and lingual surfaces is denitely necessary and all bulges and heights of convexity must be removed, especially on the mesiobuccal. The buccal and lingual proximal line angles are rounded by holding the bur parallel to the tooth’s long axis and blending the surfaces together. All angles of the preparation should be rounded to remove corners. Avoid an overtapered preparation.6. Selection of an SSC crown begins as a trial-and-error procedure. The goal is to place the smallest crown that can be seated on the tooth and to establish preexisting proximal contacts. (Helpful hint: Size 4 is a frequently used crown size for molar SSCs.) The selected SSC is tried on the preparation by seating the lingual rst and applying pressure in a buccal direction so that the crown slides over the buccal surface into the gingival sulcus. Friction should be felt as the crown slips over the buccal bulge. Some teeth are an “in-between” size, so that one crown size is too small to seat and the next larger size ts very loosely, even after contouring. Further tooth reduction, especially on the buccal and lingual surfaces, may be necessary in these cases to seat the smaller crown. After seating a crown, establish a preliminary occlusal relationship by comparing adjacent marginal ridge heights. If the crown does not seat to the same level as the adjacent teeth, the occlusal reduction may be inadequate; the crown may be too long; a gingival proximal ledge may exist; or contact may not have been broken with the adjacent tooth, preventing a complete seating of the crown. An extensive area of gingival blanching around the crown indicates that the crown is too long or is grossly overcontoured. Some crowns may need to be trimmed slightly for a better t. Crown and bridge trimming scissors, a heatless stone mounted on the low-speed straight handpiece, and a rubber wheel can be used to neatly trim and smooth an SSC. A properly trimmed crown should extend approximately 1 mm into the gingival sulcus. The margins of the nished, trimmed steel crown consist of a series of curves or arcs as determined by the marginal gingiva of the tooth being restored. There should be no corners, jagged angles, right angles, or straight lines found on these margins (see Fig. 22.16). Note: Selection of zirconia crowns is also trial and error; however, when a zirconia crown does not seat completely onto a tooth, the crown cannot be adjusted and more tooth preparation is required until the crown slides over the preparation and is completely seated when compared with adjacent teeth. If the crown ts very loosely, a smaller crown should be selected. If it does not seat completely, further reduction of the tooth will be necessary. Often the zirconia crown does not seat well because of a gingival ledge on the preparation. Do not force a zirconia crown onto the preparation. The thin zirconia margins will not ex and may break if forced over a ledge or bulge.7. Contour and crimp the SSC to form a tightly tting crown. Contouring involves bending the gingival one-third of the crown’s margins inward to restore anatomic features of the natural crown and to reduce the marginal circumference of the crown, ensuring a good t. Contouring is accomplished circumferentially with a no. 114 ball-and-socket pliers (see Fig. 22.17A) or with a no. 137 Gordon pliers. Final close adaptation of the crown is achieved by crimping the cervical margin 1 mm circumferentially. The no. 137 pliers may be used for this; special crimping pliers, such as no. 800-417 (3M ESPE; see Fig. 22.17B), are also available. A tight marginal t aids in (1) mechanical retention of the crown, (2) protection of the cement from exposure to oral uids, and (3) maintenance of gingival health. After contouring and crimping, rm resistance should be encountered when the crown is seated. After seating the crown, examine the gingival margins with an explorer for areas of poor t. Observe the gingival tissue for blanching, and examine the proximal contacts. When removing the crown, a scaler or amalgam carver can be used to engage the gingival margin and dislodge the crown. A thumb or nger should be kept over the crown during removal so that movement of the crown is controlled. Note: There is no contouring, crimping, or trimming a zirconia crown.8. The rubber dam is removed and the crown replaced so that the occlusion may be checked. Examine the occlusion bilaterally with the patient in centric occlusion. Look for movement of the crown occlusogingivally with biting pressure, and check for excessive gingival blanching. After the rubber dam is removed, special care must be taken when handling the crown in the mouth. A 2 × 2-inch gauze pad should be placed posterior to the tooth being crowned to prevent the crown from dropping into the oropharynx.9. If the SSC was trimmed, nal smoothing and polishing of the crown margin should be performed before cementation to ensure there are no jagged edges.10. Rinse and dry the SSC inside and out, and prepare to cement it. Any number of cements, including glass ionomer, polycarboxylate, or self-curing resin ionomer cement, can be used. A glass ionomer cement is preferred for SSCs. The crown is lled approximately two-thirds with cement, with all inner surfaces covered. Note: Before cementation, the inside of a zirconia crown should be free of contamination. Salivary and hemorrhagic by-products will adhere to the surface of zirconia and cannot be simply washed away. If the crown has been in contact with blood or saliva it is advisable to clean the interior by sandblasting, or use of a decontaminating agent such as Ivoclean (Ivoclar Vivadent, Amherst, NY). This will ensure maximum cement retention. A light activated resin-modied glass ionomer or bioactive cement is recommended for cementation of zirconia cement.11. Dry the tooth with compressed air and seat the SSC completely. Cement should be expressed from all margins. The handle of a mirror or the at end of a band pusher may be used to ensure complete seating, or the patient may be instructed to bite on a tongue blade. Before the cement sets, have the patient close into centric occlusion and conrm that the Steps for Preparation and Placement of Stainless Steel Crowns and Zirconia Crowns on Primary Molars• BOX 22.7 CHAPTER 22 Restorative Dentistry for the Primary Dentition 319 Stainless Steel Crown PreparationBu1–1.5 mmBuZirconia Crown PreparationBu1.5–2 mmBu1–1.5 mmBCDA• Figure 22.16 Stainless steel crown (SSC) and zirconia crown preparation. Mandibular second primary molar. (A) Proximal view. Note there is more occlusal reduction for zirconia crowns. Bu, Buccal. (B) Buccal view. Note feather-edge gingival margins on both crown preps but more proximal reduction for zirconia. (C) Occlusal view. Note for SSCs the line angles are just rounded, but circumferential reduction is neces-sary for the zirconia. (D) Mesiolingual view. For SSCs, lingual and buccal reduction is limited to beveling of the occlusal third, but for zirconia it extends subgingivally to a feather-edge. occlusion has not been altered. Note: For zirconia crowns make sure the preparation is free of saliva and blood, and seat the crown gently, tack cure the cement (if light activated), and carefully removed excess cement while keeping the crown stabilized with nger pressure. After cement removal, nish curing the cement from buccal, lingual, and occlusal directions.12. Cement must be removed from the gingival sulcus. Excessive glass ionomer cement can be removed immediately with a wet gauze and/or water spray. The interproximal areas can be cleaned by tying a knot in a piece of dental oss and drawing the oss through the interproximal region. A scaler may be needed to remove hardened cement.13. Rinse the oral cavity well, and reexamine the occlusion and the soft tissues before dismissing the patient. Note: You cannot adjust the occlusion of an SSC, and it is extremely difcult to adjust a zirconia crown. If the occlusion requires adjustment, consideration should be made to adjusting the tooth opposing the crown.Steps for Preparation and Placement of Stainless Steel Crowns and Zirconia Crowns on Primary Molars— cont’d• BOX 22.7 320 Part 3 The Primary Dentition Years: Three to Six Yearsis encountered nding the appropriate size crown because of the space loss, another alternative exists. Select a maxillary rst primary molar crown for the opposite side of the mouth and try it on the mandibular tooth. Owing to the space loss, often the mandibular tooth preparation resembles a maxillary tooth and therefore is more suited for placement of the maxillary crown. By selecting the maxillary crown for the opposite side of the mouth, the crown’s gingival margin contour in the area of the mesiobuccal cervical bulge ts the mandibular mesiobuccal cervical bulge. If several millimeters of space have been lost, it may be necessary to extract the tooth and place a space maintainer rather than struggle to place a crown on a compromised tooth preparation.Restoration of Primary Incisors and CaninesIndications for restoration of primary incisors and canines are generally based on the presence of (1) caries, (2) trauma, or (3) developmental defects of the tooth’s hard tissue. Adhesive materials, BuccalbulgeAB• Figure 22.17 (A) The buccal gingival contour of the second primary molar (left) has been described as a smile, and the buccal gingival contour of the rst primary molar has been described as a stretched-out S. Note the contour in the region of the mesiobuccal bulge of the rst primary molar. The gingival contour of all the lingual surfaces (not pictured) is a smile. (B) The proximal gingival contour of primary molars has been described as a frown because the shortest occlusocervical heights are approximately midpoint buccolingually. usually resin-based composites or resin ionomer products, are placed into class III and class V restorations in primary anterior teeth. Class IV restorations may also be done; however, if a great deal of tooth structure has been lost, full coverage with a crown will provide a superior restoration.Class III Adhesive RestorationsClass III adhesive restorations on primary incisors are very chal-lenging to do well (Fig. 22.19). Caries often extend subgingivally, making good isolation and hemorrhage control dicult. Because of the large size of the pulps of these teeth, the preparations must be kept very small. A simple slot preparation may be used, which merely removes decay and has a short cavosurface bevel.66 However, in children, especially those with bruxism, experience has revealed that retention of class III restorations solely with acid etching can be inadequate, and additional mechanical retention may be required. Retention can be gained with retentive locks on the facial or lingual BA• Figure 22.18 (A) Contouring is accomplished with a no. 114 pliers. (B) Final crimping is accomplished with a no. 800-417 pliers. (Courtesy 3M ESPE, St. Paul, MN.)ABCD• Figure 22.19 Class III cavity preparations (A, B, C: labial view). Note that a short bevel is placed on the cavosurface margin of all three prepara-tions. (A) Slot preparation with a dovetail (a frequently used class III prepa-ration). The dovetail provides additional retention. (B) Slot preparation, used for very small class III carious lesions. (C) Modied slot preparation, used when extensive gingival decalcication is evident adjacent to inter-proximal caries. (D) The interproximal box is placed perpendicular to a line tangent to the labial surface. CHAPTER 22 Restorative Dentistry for the Primary Dentition 321 AB• Figure 22.20 Class III preparation for primary canines. (A) The dovetail is usually placed on the lingual surface of maxillary canines and on the labial surface of mandibular canines. A short bevel (not shown) is placed on the cavosurface margin of preparations to be restored with resin-based composite. (B) The proximal box is placed perpendicular to a line tangent to the surface on which the dovetail is placed. 1. Administer appropriate anesthesia, and place the rubber dam. Ligation of individual teeth with dental oss provides the best stability.2. Place a wooden wedge interproximally to minimize gingival hemorrhage by depressing the papilla and protecting it from the bur.3. Create access, and remove caries with a no. 330 bur or no. 2 round bur in the high-speed handpiece, using a facial access. The axial wall is ideally placed 0.5 mm into dentin. A round bur in the low-speed handpiece can be used to remove deep decay. The gingival and lingual walls should just break contact with the adjacent tooth. It is not necessary to break contact with the incisal wall of the preparation to maintain adequate tooth structure.4. To enhance retention, a dovetail or lock may be placed on the labial or lingual surface. The lock should not extend more than halfway across the labial surface and is kept in the middle horizontal third of the tooth; or may extend across the cervical, if there is presence of cervical decalcication.5. Place a short bevel (0.5 mm) at the cavosurface margin. This may be accomplished with a ne, tapered diamond or with a ame-shaped composite nishing bur.6. Clean and dry the preparation with water and compressed air.7. Place a plastic or sectional metal matrix. Most plastic matrices will rst have to be cut in half horizontally because they are manufactured for permanent teeth and are too wide for primary teeth. The matrix is placed interproximally, and a wedge is reinserted. Note: A resin strip crown form can be trimmed to cover the preparation only (not the entire crown) to create a custom matrix, which often is easier to use than a matrix strip.8. If using a two-step bonding agent, etch the preparation for 15–20 seconds. An acid gel is preferable. Etching aids in retention and ensures improved marginal integrity and reduced marginal leakage. After etching, rinse and dry the preparation well. If a self-etching bonding agent is used, this step is eliminated.9. Place a dentin-bonding agent in the preparation with a small brush. Gently blow compressed air into the preparation to disperse a thin layer of bonding agent evenly over both dentin and enamel. Polymerize the bonding agent.10. With a plastic instrument or a pressure syringe, place the composite in the preparation. Pull the matrix tightly around the cavity preparation with nger pressure and hold until cured. Hold the visible light as closely as possible to the composite and polymerize per the manufacturer’s instructions. The light should be directed from both the facial and the lingual surfaces to ensure complete polymerization. Avoid looking directly at the polymerization light when it is turned on.11. Finishing and polishing can be performed immediately following polymerization. The smoothest and most desirable surface of a composite is that which remains after a properly adapted matrix is removed; however, it is difcult to adapt a matrix so accurately that additional adjustment to the margins is unnecessary. Gross nishing or contouring can be performed with ne-grit diamonds or with carbide nishing burs. A ame carbide nishing bur (12–20 utes) is excellent for nishing the facial and interproximal surfaces. The lingual surface is best nished with a round or pear-shaped carbide nishing bur. A lubricated, pointed white stone may also be used for smoothing. Composite polishing gloss may be used for nal polishing to create a luster-like appearance. Final interproximal polishing of the restoration is completed with sandpaper strips. These strips will be best used if they are cut into thin strips 2–3 mm in width. Mounted abrasive disks can be used to nish the facial and lingual surfaces. As an optional step, after polishing is completed, an unlled resin glaze may be added to the polished restoration. The glaze provides a better marginal seal and a smooth, nished surface. Before adding the glaze, the restoration and surrounding enamel should rst be etched for 15–20 seconds to remove surface debris. After rinsing and drying, the resin is painted onto the restoration and is polymerized. Care should be taken not to bond adjacent teeth together with the resin glaze.12. When nishing is completed, remove the rubber dam and oss the interproximal areas to check for overhangs and to remove excess glaze material.Steps in Preparation and Placement of a Class III Adhesive Restoration• BOX 22.8 surface and by beveling the cavosurface margin to increase the surface area of the enamel etched.67,68 It has been suggested that preparing the entire facial surface by 0.5 mm and veneering the surface for additional bonding can signicantly improve retention of class III restorations.69Restoring the distal surface of primary canines (Fig. 22.20) requires a preparation slightly dierent from that for incisors. e proximal box is directed at a dierent angle toward the gingiva. Either amalgam or adhesive materials may be used as the restorative material in this location. e preparation, except for a short cavosurface bevel for resin materials, is identical regardless of the restorative material chosen. A dovetail may be placed on the facial surface, except when amalgam is chosen for a maxillary canine; in that situation, the dovetail is placed on the palatal surface. e steps in preparation and placement of a class III composite restora-tion are listed in Box 22.8. 322 Part 3 The Primary Dentition Years: Three to Six YearsALTERNATIVE RESTORATIVE TREATMENTMichael J. KanellisAtraumatic restorative treatment (ART) is a minimally invasive treatment technique for restoring teeth by means of hand instrumentation for decay removal and uoride-releasing adhesive materials (glass ionomer) for lling.1 ART has been promoted by the World Health Organization as a means of delivering care in underdeveloped countries that do not have electricity or access to sophisticated dental equipment.2,3 In 2001 the American Academy of Pediatric Dentistry (AAPD) adopted a policy on ART, referring to it as “alternative restorative treatment.” The AAPD policy acknowledged that “not all dental disease can be treated by ‘traditional’ restorative techniques” and recognized ART as “a useful and benecial technique in the treatment and management of dental caries where traditional cavity preparation and placement of traditional dental restorations are not possible.”4 In 2008 the AAPD further rened their policy and included the technique in a broader discussion of “Interim Therapeutic Restorations” (ITR).5 The use of ART in developed countries has led to modications of the technique that allow for the occasional use of a slow speed handpiece and follow-up care that may include placement of a traditional restoration. Modications of the technique have led to a call by Frencken (developer and early pioneer of the ART technique) for “adherence to its original description.”6There are several potential advantages to ART when used with young children. Because hand instrumentation is used, the noise and vibration of dental handpieces is eliminated.Also eliminated is the need for acid etching, water coolant, and the accompanying high-velocity suction. Caries removal using hand instrumentation also often eliminates the need for local anesthesia. Because instrumentation is kept to a minimum, treatment can easily be carried out in the knee-to-knee position. The use of a uoride-releasing restorative material helps to prevent further decay.The use of ART in combination with silver diamine uoride, known as SMART (silver modied atraumatic restorative treatment) has been recommended because this combined approach kills bacteria prior to sealing a cavity with glass ionomer.7References1. Frencken JE, Pilot T, Songpaisan Y, et al. Atraumatic restorative treatment (ART): rationale, technique, and development. J Public Health Dent. 1996;56(3):135–140.2. Phantumvanit P, Songpaisan Y, Pilot T, et al. Atraumatic restorative treatment (ART): a three-year community eld trial in Thailand—survival of one-surface restorations in the permanent dentition. J Public Health Dent. 1996;56(3):141–145.3. World Health Organization. Revolutionary new procedure for treating dental caries. Press Release WHO/28. April 7, 1994.4. American Academy of Pediatric Dentistry Council on Clinical Affairs. Policy on alternative restorative treatment (ART). Pediatr Dent. 2005–2006;27(suppl 7):30.5. American Academy of Pediatric Dentistry Council on Clinical Affairs. Policy on interim therapeutic restorations (ITR). Pediatr Dent. 2010–2011;32(6 Special Issue):39.6. Frencken JE, Leal SC. The correct use of the ART approach. J Appl Oral Sci. 2010;18(1):1–4.7. Fa BA, Jew JA, Wong A, et al. Silver modied atraumatic restorative technique (SMART): an alternative caries prevention tool. Stoma EDU J. 2016;3(2).Class V Restorations for Incisors and CaninesClass V restorations may be adhesive materials (most frequently) or amalgams. ey are most often needed on the facial surface of canines. To prepare these restorations, penetrate the tooth in the area of caries with a no. 330 bur until dentin is reached (approxi-mately 1 mm from the outer enamel surface). Move the bur laterally into sound dentin and enamel, thus establishing the walls of the cavity. e pulpal wall should be convex, parallel to the outer enamel surface. e lateral walls are slightly ared near the proximal surfaces to prevent undermining of the enamel. e nal external outline is determined by the extent of caries. Mechanical retention in the preparation can be achieved with a no. 35 inverted cone bur or a no. 12 round bur, creating small undercuts in the gingi-voaxial and incisoaxial line angles. For resin-based composites, a short bevel is placed around the entire cavosurface margin. Etching, bonding, material placement, and nishing are like that described for class III adhesive restorations, except that no matrix is used.Full Coronal Coverage of IncisorsIndications70e indications for full coverage of incisors are as follows:• Incisorswithlargeinterproximallesions,orlargelesionscoveringa single surface (e.g., lingual surfaces in nursing caries)• Incisorsthathavereceivedpulptherapy• Incisorsthathavebeenfracturedandhavelostanappreciableamount of tooth structure• Incisorswithmultiplehypoplasticdefectsordevelopmentaldisturbances (e.g., ectodermal dysplasia)• Discoloredincisorsthatareestheticallyunpleasing• Incisorswithsmallinterproximallesionsthatalsodemonstratelarge areas of cervical decalcication (i.e., high caries risk)It is a challenging task to repair extensively destroyed anterior teeth with restorations that are durable, retentive, and esthetic (see Fig. 22.19). ere are several methods of providing full coronal coverage to primary incisors, but adhesive resin–based composite crowns (Strip Crowns [3M ESPE]) (see Fig. 22.19B), preveneered SSCs (e.g., Kinder Krowns [Kinder Krowns, St. Louis Park, MN], NuSmile Primary Crowns [NuSmile Crowns]), and preformed primary ZCs (e.g., EZ Pedo, Loomis, CA; NuSmile ZR Crowns) are the most popular methods. A survey published in 2010 of pediatric dentists reported that 46% of respondents preferred strip crowns for treatment of decayed primary incisors, and 41% preferred veneered crowns.71 is survey was published prior to the widespread introduction of zirconia primary crowns, which have gained much popularity. Other considerably less popular options include plain SSCs and open face SSCs (see Fig. 22.19C). All have shortcomings (Table 22.3) but may still be used in certain situations. Plain SSCs provide a very durable restoration but are esthetically unpleasing to most parents. Open-face crowns72 are used by some clinicians because their retention is superior to that of adhesive resin crowns; however, esthetic results are compromised. A very esthetic and frequently placed crown is the adhesive resin–based composite crown or “strip” crown. Studies have shown that these crowns demonstrate clinically satisfactory results with good durability and have high parental acceptance.73,74 Preveneered crowns are both esthetic and durable but may show some metal and can demonstrate chipping of the veneer. As stated earlier in the chapter, there is still not a lot of clinical information available about zirconia ceramic crowns for primary teeth; however, ZCs in adults have been shown to be very esthetic, durable, stain resistant, biocompatible, and CHAPTER 22 Restorative Dentistry for the Primary Dentition 323 Technique Esthetics Durability Time for Placement Selection CriteriaResin (strip) crownsaVery good initially; may discolor over timeRetention dependent on amount of tooth structure present and quality of acid etchCan be dislodged fairly easily if traumatizedTime required for optimum isolation, etching, placement, nishingWhen esthetics is a great concernAdequate tooth structure remains for etching/bondingChild is not highly prone to traumaGingival hemorrhage is controllableZirconia ceramic crownsaVery good Ceramic is very durable, rarely chips or breaksLike a preveneered crown (prep must t the crown form)Adequate tooth structure remains, similar to a strip crownEsthetics of great concernPrefabricated veneered steel crownsVery good Good; however, facings may occasionally chip or fractureComparable to strip crowns; however, must make tooth t the crown, which adds timeEsthetics is a concernHemorrhage difcult to controlChildren with history of bruxismSteel crownsbVery poor Very good; a well-crimped, cemented crown is very retentive and wears wellFastest crown to place Severely decayed teethEsthetics of no concernUnable to control gingival hemorrhageNeed to place restoration quickly because of inadequate cooperation or timeOpen-face steel crownsGood; however, usually some metal showsGood; like steel crowns, are very retentive; however, facings may be dislodgedMay take the longest to place because of two-step procedure:1. Crown placement2. Composite placementSeverely decayed teethDurability needed: active, accident-prone child or severe bruxism evidentaRestoration of choice esthetically.bAvoid using because of esthetics.Comparison of Full Coverage Techniques for Primary IncisorsTABLE 22.3 ALTERNATIVE RESTORATIVE TREATMENT—cont’dDCBA(A) Facial caries evident on incisors and cuspid. (B) Spoon excavator positioned for decay removal. (C) Following caries removal with spoon excava-tor. (D) Teeth restored with glass ionomer restorative material.

Related Articles

Leave A Comment?