Immediate Implant Placement Surgical Protoco










830
32
Immediate Implant
Placement Surgical Protocol
RANDOLPH R. RESNIK
T
he traditional dental implant placement protocol is
a proven and reliable treatment modality to restore
edentulous spaces. However, a healing period is usually
required after extraction and/or graft, which delays the implant
placement and ultimately the placement of the nal prosthe-
sis. is extended treatment time leaves the patient without
teeth and usually an interim prosthesis. Since the 1980s these
conventional treatment protocols have been challenged to be
replaced with other options that are geared toward shorter
treatment times. Classications have been reported to clarify
the placement of dental implants according to various time
intervals after tooth extraction.
e placement of dental implants at the time of tooth extrac-
tion (immediate implants) has been shown to be a viable treat-
ment protocol in implant dentistry today.
1-4
e objectives of
immediate implant placement are the same as for conventional
staged treatment: implant primary stability, sucient rigid
xation after healing, ideal positioning for implant restoration,
and an ideal esthetic result. Immediate implant placement
has become extremely popular because these objectives can be
obtained with fewer procedures, less treatment time, and less
cost to the patient. However, immediate placement implants
are more demanding and require a special skill set from the
implant clinician. e surgical procedure and prosthetic reha-
bilitation are more complex, with multiple factors that may
lead to an increased morbidity or complications. erefore this
chapter will address the immediate placement protocol with a
comprehensive evaluation of treatment planning and specic
factors related to site-specic recommendations and the pre-
vention of complications (Fig. 32.1) Box 32.1.
Advantages of Immediate Implant
Placement
Decreased Treatment Time and Cost
e immediate placement procedure reduces the number of surgical
appointments because no postoperative healing period is required.
Because of the decreased number of surgical appointments, patient
discomfort and morbidity are decreased. In addition, less chair time
is required, which reduces the overall cost of the procedure.
Decreased Need for Bone Augmentation
Because the implant is placed at the same time as extraction, the
bone remodeling process does not take place in which bone resorbs
from the facial to the lingual, often resulting in compromised bone
dimensions. If no immediate implant or grafting is completed at the
time of extraction, resorption has been shown to result in approxi-
mately 1 to 2 mm of vertical bone height and 4 to 5 of horizontal
bone width within 1 to 3 years.
5
Additional studies have shown
that at 6 months after extraction, bone healing averages approxi-
mately 1.24 mm vertical bone loss (range 0.9–3.6 mm) and 3.79
mm horizontal bone decrease (range 2.46–4.56 mm) (Fig. 32.2).
6
Preservation of the Soft Tissue Drape
An additional benet of immediate implant insertion after tooth
extraction is related to the preservation of the soft tissue drape.
Most often after tooth extraction, the soft tissue drape is lost and
becomes compromised. e immediate implant placement tech-
nique has been described as a “preservation technique,” because
the gingival architecture is preserved. If the soft tissue drape is
not maintained, “black triangles” will result in the interproximal
areas, which compromises long-term esthetics and/or contributes
to peri-implant disease (Fig. 32.3).
Improved Implant Positioning
Because the implant is placed into the existing extraction site, the
ideal implant positioning is much easier for the clinician. In a
staged implant protocol, often the available bone is not in the
• Immediate=attimeofextraction
• Early=4–6weeksafterextraction
• Delayed=3–4monthsafterextraction
• Late=>4monthsaftertoothextraction
BOX
32.1
Implant Placement Denitions
1

831
CHAPTER 32 Immediate Implant Placement Surgical Protocol
D
A B
C
Fig. . Immediate Placement Implant. (A) Nonrestorable maxillary second bicuspid fracture. (B and
C) Verification of initial pilot and final drill engaging bone apical to root apex. (D) Final immediate implant
placement.
AB
C
Fig. . (A) Existing tooth root supporting the buccal plate. (B) Immedi-
ate implant supports the buccal plate. (C) Diagram depicting resorption of
buccal bone requiring bone graft before implant placement.
Fig. . Immediate implant placement with minimal soft tissue reflec-
tion allows for the preservation of the soft tissue drape and results in mini-
mal recession.

832
PART VI Implant Surgery
ideal position (i.e., the ridge is positioned more lingually), which
leads to nonideal implant placement, with resultant implant pros-
thesis complications (Box 32.2).
Disadvantages of Immediate Placement
Site Morphology
After tooth extraction the dimensions of the remaining socket
(i.e., mesial-distal and buccal-lingual dimensions) are usually
much dierent from the implant diameter. erefore a discrep-
ancy is present between the implant diameter and the morphology
of the socket, which results in bony defects. For example, the max-
illary molar has an 8.0-mm mesial-distal average cervix diameter
and a 10.0-mm buccal-lingual diameter. After extraction, usually
a 5.0- or 6.0-mm diameter is inserted that leaves a 2.0- to 3.0-mm
(mesial-distal) and a 4.0- to 5.0-mm buccal-lingual discrepancy
(Fig. 32.4).
Surgical Technique Is More Complicated
Placement of an implant into an extraction site is usually much
more surgically demanding. e techniques are site specic and
usually do not follow standard manufacturers’ surgical place-
ment protocols. Most notably, it is often dicult to achieve
primary stability because of poor bone density or compromised
bone quantity (Fig. 32.5).
Anatomic Limitations
It is often necessary to deepen the osteotomy 2 to 4 mm apical
to the existing extraction socket (apical wall) to obtain primary
stability. is may result in impingement on vital structures,
resulting in neurosensory impairments, perforation into the max-
illary sinus or nasal cavity, or perforation of the cortical plates.
In the maxillary anterior the nasal cavity may be penetrated, and
in the posterior the maxillary sinus may be violated, which can
predispose the patient to rhinosinusitis. In the mandibular pos-
terior, extending the osteotomy deeper may lead to violation of
the mandibular canal and resultant nerve damage (i.e., especially
common in type 1 nerve positions) or lingual plate perforation
(Fig. 32.6).
Lack of Primary Closure
It is usually dicult or even impossible to obtain primary clo-
sure after tooth extraction and immediate implant placement.
Unless a large incision is made and the tissue stretched, it is
often challenging to approximate the tissues. erefore usually
a membrane will be required to be placed over the extraction
site. Making larger broad-based incisions with vertical releases
incisions results in compromised blood supply and is usually not
warranted. In some cases, when compromised keratinized tissues
exist, free tissue, subepithelial, or connective tissue grafts may
be indicated after stage I healing to restore the facial attached
keratinized tissue.
Presence of Acute/Chronic Pathology
Although studies have shown immediate implants may be suc-
cessfully placed after extraction of teeth into infected sites, there
is obviously an increased risk. Because residual bacteria may be
present after an extraction, healing may be aected and mor-
bidity higher. If exudate is present, the pH is lowered, which
• Decreasedtreatmenttimeandcost
• Decreasedneedforboneaugmentation
• Preservationofthesofttissuedrape
• Improvedimplantpositioning
• Highpatientsatisfaction
BOX
32.2
Advantages of Immediate Placement
Fig. . Poor Site Morphology: Mandibular extraction resulting in mini-
mal bone for immediate implant placement.
Fig. . Surgical placement into an extraction site requires an increased
skill set.

833
CHAPTER 32 Immediate Implant Placement Surgical Protocol
may cause solution-mediated resorption of the grafted bone
and contamination of the implant body because of a bacterial
smear layer. erefore implant placement into an infected site
is a controversial topic in implant dentistry, and the implant
clinician must be conscious of the possible associated complica-
tions (Fig. 32.7).
Consequences of Implant Failure
If implant failure results from an immediate implant, signicant
complications may occur. Usually the need for bone augmen-
tation will result, which delays treatment and increases costs.
Studies have shown that a replacement implant (second time)
has a success rate of approximately 71%, and a third replace-
ment has a success rate of approximately 60% (Fig. 32.8 and
Box 32.3).
7,8
erefore, implant failure may lead to many nan-
cial and patient related issues.
AB
C
Fig. . Anatomic Limitations. (A) Maxillary implant penetrating the nasal cavity. (B) Maxillary molar
showing no host bone present for immediate implant placement because of the maxillary sinus location.
(C) Implant placement positioned more apical to root socket, which impinges on the mandibular canal.
Fig. . Postextraction site exhibiting acute pathology.

PART VI Implant Surgery
Immediate Implant Studies
Immediate placement implants were rst reported by Lazzara in
1989.
1
In his studies, he documented the placement of implants at
the time of extraction with the use of barrier membranes. Becker
et al.
9,10
in 1999 reported a 93.3% survival rate for implants
placed at the time of extraction and grafted with barrier mem-
branes after 1 and 5 years after loading. Since then, a full array
of studies has conrmed the success and predictability of placing
implants at the time of extraction.
11,12
Peñarrocha-Diago etal.
13
evaluated immediate versus nonimmediate placement of implants
for full-arch xed restorations. ey determined that the immedi-
ate group had a higher success rate (97.7%) versus the nonimme-
diate group (96.3%).
Treatment Planning Considerations
Available Bone
e concept of available bone is generally accepted as a primary
determinant of implant placement viability. Available bone
describes the amount of bone in an extraction site considered
for implantation. It is measured in width, height, length, angula-
tion, and crown height space (Fig. 32.9). As a general guideline,
1.5 to 2 mm of surgical error is maintained between the implant
and any adjacent landmark or vital structure. is is especially
critical when the opposing landmark is the mandibular inferior
alveolar nerve.
When evaluating available bone in an immediate extraction
site, the implant clinician must consider the dimension of the
extraction socket and the defect between the labial plate of bone
and the proposed position of the implant. e resultant defect may
be deceiving. For example, most anterior teeth have a faciopala-
tal dimension that is far greater than its mesiodistal dimension.
When an anterior tooth requires extraction, during the extraction
process the thin facial cortex often becomes compromised or lost.
As a result the buccal cortex is almost always several millimeters
apical to the palatal cortical plate, and frequently bone grafting
and/or membrane placement in conjunction with the implant
insertion are indicated.
Bone Height
e height of available bone is measured from the crest of the
edentulous ridge to the opposing landmark. e anterior regions
are limited by the maxillary nares or the inferior border of the
mandible. e anterior regions of the jaws have the greatest height
because the maxillary sinus and inferior alveolar nerve limit this
dimension in the posterior regions. e maxillary canine emi-
nence region often oers the greatest height of available bone in
the maxillary anterior.
1
In the posterior jaw region there is usually
greater bone height in the maxillary rst premolar than in the
second premolar, which has greater height than the molar sites
because of the concave morphology of the maxillary sinus oor.
Likewise, the mandibular rst premolar region is usually anterior
to the mental foramen and provides the most vertical column
of bone in the posterior mandible. However, on occasion, this
premolar site may present a reduced height compared with the
anterior region because of the presence of an anterior loop of the
mandibular canal. e nerve courses anteriorly below the foramen
and proceeds superiorly, then distally, before its exit through the
mental foramen. Posterior nerve anatomy has particular signi-
cance with regard to immediate implant placement. Primary sta-
bility for immediately placed implants is frequently achieved using
bone apical to the extraction site. In the posterior mandible the
course of the inferior alveolar nerve can vary from type 1 to type
3, with associated available apical bone ranging from nonexistent
to sucient and surgical risk varying accordingly. In addition,
variants of the mental foramen exist that can increase the pos-
sibility of injury to the inferior alveolar nerve during immediate
implant placement in the region (Fig. 32.10). e available bone
height in an edentulous site is the most important dimension for
implant consideration because it aects both implant length and
crown height. Crown height aects force factors and esthetics. In
addition, vertical bone augmentation, if needed, is less predictable
than width augmentation.
Bone Width
e width of available bone is measured between the facial and
lingual plates at the crest of the potential implant site. It is the next
most signicant criterion aecting long-term survival of endosteal
implants. e crestal aspect of the residual ridge is often cortical in
nature and exhibits greater density than the underlying trabecular
bone regions, especially in the mandible.
Accordingly, the lack of crestal bone at an extraction site makes
the achievement of primary stability more challenging for imme-
diate implant placement. Facial dehiscence defects commonly
found after tooth extraction and immediate implant placement
Fig. . Immediate Implant Failure: Large defect resulting from the loss
of an immediate implant resulting no buccal plate remaining and missing
mesial bone.
• Sitemorphology
• Surgicaltechniqueismorecomplicated
• Anatomiclimitations
• Lackofprimaryclosure
• Presenceofacute/chronicpathology
• Consequencesofimplantfailure
BOX
32.3
Disadvantages of Immediate Placement
834

A
DB
C
Fig. . Anatomic limitations for immediate implant treatment planning: (A) Floor of the nasal cavity. (B)Infe-
rior border of the maxillary sinus. (C) Lingual cortical plate of the inferior mandible. (D) Inferior alveolar canal.
A B
Fig. . Proximity of the Mental Foramen to the Premolar Apices. (A) In 25% to 38% of cases the
mental foramen is superior to the premolar apex. (B) Three-dimensional image depicting a premolar root
in the mental foramen.

836
PART VI Implant Surgery
have been shown to have more compromised healing compared
with infrabony defects (Fig. 32.11).
9
Bone Length
Bone length is dened as the mesiodistal length of bone in a postex-
traction area. It is most often limited by adjacent teeth or implants.
As a general rule the implant should be at least 1.5 mm from an
adjacent tooth and 3 mm from an adjacent implant. ese mea-
surements not only allow surgical error but also compensates for
the width of an implant or tooth crestal defect, which is usually
less than 1.4 mm and may vary with implant diameter and thread
design. As a result, if bone loss occurs around the crest module of an
implant or around a tooth with periodontal disease, the associated
vertical bone defect will not typically expand into horizontal defect
and thereby cause bone loss on the adjacent structure (Fig. 32.12).
Bone Angulation
Bone angulation is an additional determinant for available bone
(Fig. 32.13). e initial alveolar bone angulation represents the
natural tooth root trajectory in relation to the occlusal plane. Ide-
ally it is perpendicular to the plane of occlusion, which is aligned
with the forces of occlusion and is parallel to the long axis of
the prosthodontic restoration. e incisal and occlusal surfaces
of the teeth follow the curve of Wilson and curve of Spee. As
such, the roots of the maxillary teeth are angled toward a com-
mon point approximately 4 inches away. e mandibular roots
are, so the anatomic crowns are more lingually inclined in the
posterior regions and labially inclined in the anterior area com-
pared with the underlying roots. e mandibular rst premolar
cusp tip is usually vertical to its root apex. e maxillary anterior
teeth are the only segment in either arch that does not receive a
long axis load to the tooth roots, but instead are usually loaded
at a 12-degree angle. As such, their root diameter is greater than
the mandibular anterior teeth. In all other regions the teeth are
loaded perpendicular to the curves of Wilson or Spee. e ante-
rior sextants may have labial undercuts that often mandate greater
angulation of the implants or concurrent grafting of the site after
insertion. e narrower width ridge often requires a root form
implant design that is likewise narrower. Compared with larger
diameters, smaller-diameter designs cause greater crestal stress and
may not oer the same range of custom abutments. In addition,
the narrower width of bone does not permit as much latitude in
placement regarding angulation within the bone. is limits the
acceptable angulation of bone in the narrow ridge to 20 degrees
from the axis of the adjacent clinical crowns or a line perpendicu-
lar to the occlusal plane.
14
e angulation of available bone in the
maxillary rst premolar region may place the adjacent cuspid at
risk during implant placement.
Esthetic Risk
Especially in the anterior region, extracting a tooth with the
immediate implant placement may result in nonideal esthetic
issues. erefore the patient should be evaluated preoperatively
for the following esthetic parameters: lip line in relation to the
A
B
Fig. . Evaluation of Width: (A) Bone width may be measured on CBCT cross-section, (B) Evaluation by interactive treatment planning with implant
placement.
Fig. . Cone beam computed tomographic three-dimensional axial
image measuring the length between two root tips.

837
CHAPTER 32 Immediate Implant Placement Surgical Protocol
teeth and gingival margins, presence and position of interproximal
papilla, shape and shade of adjacent teeth, presence of restorations
on adjacent teeth, and a hard and soft tissue thickness analysis. In
some cases, even with an ideal esthetic result, possible limitations
may deem the placement of implants nonideal (Fig. 32.14).
Type of Prosthesis
e clinician must always be proactive in the evaluation and
anticipation of the nal prosthesis and its associated dimensions
of crown height space, whether for a single-tooth crown or full-
arch prosthesis. In clinical situations where tooth extraction will
result in an edentulous arch, an alveoloplasty may need to be
completed to satisfy the need for additional space. In completely
edentulous patients, alveoplasty may result in the complete
obliteration of the residual socket. is is imperative because
sucient crown height space is needed for an overdenture and
attachment, whereas minimal reduction is required when a type
3 xed prosthesis (FP-3) is treatment planned. When considering
immediate implant placement for partially edentulous patients,
the anatomic dimensions of the edentulous space must be evalu-
ated. In some cases the opposing arch may need to be modied,
or possible orthodontic treatment to realign or reposition the
dentition (Fig. 32.15).
Bone Density
Bone quality or density refers to the internal structure of bone
and reects a number of its biomechanical properties, such as
strength and modulus of elasticity. e density of available bone
in a potential implant site is a determining factor in treatment
planning, implant design, surgical approach, healing time, and
initial progressive bone loading during prosthetic reconstruction.
e quality of bone is often dependent on the arch position. e
densest bone is usually observed in the anterior mandible, with
less dense bone in the anterior maxilla and posterior mandible,
and the least dense bone typically found in the posterior maxilla.
In addition to arch location, several authors have reported dier-
ent failure rates related to the quality of the bone. Johns etal.
15
reported a higher failure rate in the maxilla (poorer bone quality)
in comparison with the mandible (more favorable bone density).
Smedberg etal.
16
reported a 36% failure rate in the poorest bone
density. e reduced implant survival most often is more related
to bone density than arch location. In a 15-year follow-up study,
Herrmann etal.
17
found implant failures were strongly correlated
to patient factors, including bone quality, especially when cou-
pled with poor bone volume. Bone quality is directly related to
the ability to achieve an acceptable level of primary xation for
Fig. . Cone beam computed tomographic image determining ideal
angulation.
Fig. . Maxillary lateral incisor resulting in poor esthetics because of
a facially placed immediate implant placement.
Fig. . Immediate placement resulting in poor esthetics and periodon-
tal complications because of positioning too deep and poor angulation.

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83032Immediate Implant Placement Surgical ProtocolRANDOLPH R. RESNIKThe traditional dental implant placement protocol is a proven and reliable treatment modality to restore edentulous spaces. However, a healing period is usually required after extraction and/or graft, which delays the implant placement and ultimately the placement of the nal prosthe-sis. is extended treatment time leaves the patient without teeth and usually an interim prosthesis. Since the 1980s these conventional treatment protocols have been challenged to be replaced with other options that are geared toward shorter treatment times. Classications have been reported to clarify the placement of dental implants according to various time intervals after tooth extraction.e placement of dental implants at the time of tooth extrac-tion (immediate implants) has been shown to be a viable treat-ment protocol in implant dentistry today.1-4 e objectives of immediate implant placement are the same as for conventional staged treatment: implant primary stability, sucient rigid xation after healing, ideal positioning for implant restoration, and an ideal esthetic result. Immediate implant placement has become extremely popular because these objectives can be obtained with fewer procedures, less treatment time, and less cost to the patient. However, immediate placement implants are more demanding and require a special skill set from the implant clinician. e surgical procedure and prosthetic reha-bilitation are more complex, with multiple factors that may lead to an increased morbidity or complications. erefore this chapter will address the immediate placement protocol with a comprehensive evaluation of treatment planning and specic factors related to site-specic recommendations and the pre-vention of complications (Fig. 32.1) Box 32.1.Advantages of Immediate Implant PlacementDecreased Treatment Time and Coste immediate placement procedure reduces the number of surgical appointments because no postoperative healing period is required. Because of the decreased number of surgical appointments, patient discomfort and morbidity are decreased. In addition, less chair time is required, which reduces the overall cost of the procedure. Decreased Need for Bone AugmentationBecause the implant is placed at the same time as extraction, the bone remodeling process does not take place in which bone resorbs from the facial to the lingual, often resulting in compromised bone dimensions. If no immediate implant or grafting is completed at the time of extraction, resorption has been shown to result in approxi-mately 1 to 2 mm of vertical bone height and 4 to 5 of horizontal bone width within 1 to 3 years.5 Additional studies have shown that at 6 months after extraction, bone healing averages approxi-mately 1.24 mm vertical bone loss (range 0.9–3.6 mm) and 3.79 mm horizontal bone decrease (range 2.46–4.56 mm) (Fig. 32.2).6 Preservation of the Soft Tissue DrapeAn additional benet of immediate implant insertion after tooth extraction is related to the preservation of the soft tissue drape. Most often after tooth extraction, the soft tissue drape is lost and becomes compromised. e immediate implant placement tech-nique has been described as a “preservation technique,” because the gingival architecture is preserved. If the soft tissue drape is not maintained, “black triangles” will result in the interproximal areas, which compromises long-term esthetics and/or contributes to peri-implant disease (Fig. 32.3). Improved Implant PositioningBecause the implant is placed into the existing extraction site, the ideal implant positioning is much easier for the clinician. In a staged implant protocol, often the available bone is not in the • Immediate=attimeofextraction• Early=4–6weeksafterextraction• Delayed=3–4monthsafterextraction• Late=>4monthsaftertoothextraction • BOX 32.1 Implant Placement Denitions1 831CHAPTER 32 Immediate Implant Placement Surgical ProtocolDA BC• Fig. . Immediate Placement Implant. (A) Nonrestorable maxillary second bicuspid fracture. (B and C) Verification of initial pilot and final drill engaging bone apical to root apex. (D) Final immediate implant placement.ABC• Fig. . (A) Existing tooth root supporting the buccal plate. (B) Immedi-ate implant supports the buccal plate. (C) Diagram depicting resorption of buccal bone requiring bone graft before implant placement.• Fig. . Immediate implant placement with minimal soft tissue reflec-tion allows for the preservation of the soft tissue drape and results in mini-mal recession. 832PART VI Implant Surgeryideal position (i.e., the ridge is positioned more lingually), which leads to nonideal implant placement, with resultant implant pros-thesis complications (Box 32.2). Disadvantages of Immediate PlacementSite MorphologyAfter tooth extraction the dimensions of the remaining socket (i.e., mesial-distal and buccal-lingual dimensions) are usually much dierent from the implant diameter. erefore a discrep-ancy is present between the implant diameter and the morphology of the socket, which results in bony defects. For example, the max-illary molar has an 8.0-mm mesial-distal average cervix diameter and a 10.0-mm buccal-lingual diameter. After extraction, usually a 5.0- or 6.0-mm diameter is inserted that leaves a 2.0- to 3.0-mm (mesial-distal) and a 4.0- to 5.0-mm buccal-lingual discrepancy (Fig. 32.4). Surgical Technique Is More ComplicatedPlacement of an implant into an extraction site is usually much more surgically demanding. e techniques are site specic and usually do not follow standard manufacturers’ surgical place-ment protocols. Most notably, it is often dicult to achieve primary stability because of poor bone density or compromised bone quantity (Fig. 32.5). Anatomic LimitationsIt is often necessary to deepen the osteotomy 2 to 4 mm apical to the existing extraction socket (apical wall) to obtain primary stability. is may result in impingement on vital structures, resulting in neurosensory impairments, perforation into the max-illary sinus or nasal cavity, or perforation of the cortical plates. In the maxillary anterior the nasal cavity may be penetrated, and in the posterior the maxillary sinus may be violated, which can predispose the patient to rhinosinusitis. In the mandibular pos-terior, extending the osteotomy deeper may lead to violation of the mandibular canal and resultant nerve damage (i.e., especially common in type 1 nerve positions) or lingual plate perforation (Fig. 32.6). Lack of Primary ClosureIt is usually dicult or even impossible to obtain primary clo-sure after tooth extraction and immediate implant placement. Unless a large incision is made and the tissue stretched, it is often challenging to approximate the tissues. erefore usually a membrane will be required to be placed over the extraction site. Making larger broad-based incisions with vertical releases incisions results in compromised blood supply and is usually not warranted. In some cases, when compromised keratinized tissues exist, free tissue, subepithelial, or connective tissue grafts may be indicated after stage I healing to restore the facial attached keratinized tissue. Presence of Acute/Chronic PathologyAlthough studies have shown immediate implants may be suc-cessfully placed after extraction of teeth into infected sites, there is obviously an increased risk. Because residual bacteria may be present after an extraction, healing may be aected and mor-bidity higher. If exudate is present, the pH is lowered, which • Decreasedtreatmenttimeandcost• Decreasedneedforboneaugmentation• Preservationofthesofttissuedrape• Improvedimplantpositioning• Highpatientsatisfaction • BOX 32.2 Advantages of Immediate Placement• Fig. . Poor Site Morphology: Mandibular extraction resulting in mini-mal bone for immediate implant placement.• Fig. . Surgical placement into an extraction site requires an increased skill set. 833CHAPTER 32 Immediate Implant Placement Surgical Protocolmay cause solution-mediated resorption of the grafted bone and contamination of the implant body because of a bacterial smear layer. erefore implant placement into an infected site is a controversial topic in implant dentistry, and the implant clinician must be conscious of the possible associated complica-tions (Fig. 32.7). Consequences of Implant FailureIf implant failure results from an immediate implant, signicant complications may occur. Usually the need for bone augmen-tation will result, which delays treatment and increases costs. Studies have shown that a replacement implant (second time) has a success rate of approximately 71%, and a third replace-ment has a success rate of approximately 60% (Fig. 32.8 and Box 32.3).7,8 erefore, implant failure may lead to many nan-cial and patient related issues. ABC• Fig. . Anatomic Limitations. (A) Maxillary implant penetrating the nasal cavity. (B) Maxillary molar showing no host bone present for immediate implant placement because of the maxillary sinus location. (C) Implant placement positioned more apical to root socket, which impinges on the mandibular canal.• Fig. . Postextraction site exhibiting acute pathology. PART VI Implant SurgeryImmediate Implant StudiesImmediate placement implants were rst reported by Lazzara in 1989.1 In his studies, he documented the placement of implants at the time of extraction with the use of barrier membranes. Becker et al.9,10 in 1999 reported a 93.3% survival rate for implants placed at the time of extraction and grafted with barrier mem-branes after 1 and 5 years after loading. Since then, a full array of studies has conrmed the success and predictability of placing implants at the time of extraction.11,12 Peñarrocha-Diago etal.13 evaluated immediate versus nonimmediate placement of implants for full-arch xed restorations. ey determined that the immedi-ate group had a higher success rate (97.7%) versus the nonimme-diate group (96.3%). Treatment Planning ConsiderationsAvailable Bonee concept of available bone is generally accepted as a primary determinant of implant placement viability. Available bone describes the amount of bone in an extraction site considered for implantation. It is measured in width, height, length, angula-tion, and crown height space (Fig. 32.9). As a general guideline, 1.5 to 2 mm of surgical error is maintained between the implant and any adjacent landmark or vital structure. is is especially critical when the opposing landmark is the mandibular inferior alveolar nerve.When evaluating available bone in an immediate extraction site, the implant clinician must consider the dimension of the extraction socket and the defect between the labial plate of bone and the proposed position of the implant. e resultant defect may be deceiving. For example, most anterior teeth have a faciopala-tal dimension that is far greater than its mesiodistal dimension. When an anterior tooth requires extraction, during the extraction process the thin facial cortex often becomes compromised or lost. As a result the buccal cortex is almost always several millimeters apical to the palatal cortical plate, and frequently bone grafting and/or membrane placement in conjunction with the implant insertion are indicated.Bone Heighte height of available bone is measured from the crest of the edentulous ridge to the opposing landmark. e anterior regions are limited by the maxillary nares or the inferior border of the mandible. e anterior regions of the jaws have the greatest height because the maxillary sinus and inferior alveolar nerve limit this dimension in the posterior regions. e maxillary canine emi-nence region often oers the greatest height of available bone in the maxillary anterior.1 In the posterior jaw region there is usually greater bone height in the maxillary rst premolar than in the second premolar, which has greater height than the molar sites because of the concave morphology of the maxillary sinus oor. Likewise, the mandibular rst premolar region is usually anterior to the mental foramen and provides the most vertical column of bone in the posterior mandible. However, on occasion, this premolar site may present a reduced height compared with the anterior region because of the presence of an anterior loop of the mandibular canal. e nerve courses anteriorly below the foramen and proceeds superiorly, then distally, before its exit through the mental foramen. Posterior nerve anatomy has particular signi-cance with regard to immediate implant placement. Primary sta-bility for immediately placed implants is frequently achieved using bone apical to the extraction site. In the posterior mandible the course of the inferior alveolar nerve can vary from type 1 to type 3, with associated available apical bone ranging from nonexistent to sucient and surgical risk varying accordingly. In addition, variants of the mental foramen exist that can increase the pos-sibility of injury to the inferior alveolar nerve during immediate implant placement in the region (Fig. 32.10). e available bone height in an edentulous site is the most important dimension for implant consideration because it aects both implant length and crown height. Crown height aects force factors and esthetics. In addition, vertical bone augmentation, if needed, is less predictable than width augmentation. Bone Widthe width of available bone is measured between the facial and lingual plates at the crest of the potential implant site. It is the next most signicant criterion aecting long-term survival of endosteal implants. e crestal aspect of the residual ridge is often cortical in nature and exhibits greater density than the underlying trabecular bone regions, especially in the mandible.Accordingly, the lack of crestal bone at an extraction site makes the achievement of primary stability more challenging for imme-diate implant placement. Facial dehiscence defects commonly found after tooth extraction and immediate implant placement • Fig. . Immediate Implant Failure: Large defect resulting from the loss of an immediate implant resulting no buccal plate remaining and missing mesial bone.• Sitemorphology• Surgicaltechniqueismorecomplicated• Anatomiclimitations• Lackofprimaryclosure• Presenceofacute/chronicpathology• Consequencesofimplantfailure • BOX 32.3 Disadvantages of Immediate Placement834 ADBC• Fig. . Anatomic limitations for immediate implant treatment planning: (A) Floor of the nasal cavity. (B)Infe-rior border of the maxillary sinus. (C) Lingual cortical plate of the inferior mandible. (D) Inferior alveolar canal.A B• Fig. . Proximity of the Mental Foramen to the Premolar Apices. (A) In 25% to 38% of cases the mental foramen is superior to the premolar apex. (B) Three-dimensional image depicting a premolar root in the mental foramen. 836PART VI Implant Surgeryhave been shown to have more compromised healing compared with infrabony defects (Fig. 32.11).9 Bone LengthBone length is dened as the mesiodistal length of bone in a postex-traction area. It is most often limited by adjacent teeth or implants. As a general rule the implant should be at least 1.5 mm from an adjacent tooth and 3 mm from an adjacent implant. ese mea-surements not only allow surgical error but also compensates for the width of an implant or tooth crestal defect, which is usually less than 1.4 mm and may vary with implant diameter and thread design. As a result, if bone loss occurs around the crest module of an implant or around a tooth with periodontal disease, the associated vertical bone defect will not typically expand into horizontal defect and thereby cause bone loss on the adjacent structure (Fig. 32.12). Bone AngulationBone angulation is an additional determinant for available bone (Fig. 32.13). e initial alveolar bone angulation represents the natural tooth root trajectory in relation to the occlusal plane. Ide-ally it is perpendicular to the plane of occlusion, which is aligned with the forces of occlusion and is parallel to the long axis of the prosthodontic restoration. e incisal and occlusal surfaces of the teeth follow the curve of Wilson and curve of Spee. As such, the roots of the maxillary teeth are angled toward a com-mon point approximately 4 inches away. e mandibular roots are, so the anatomic crowns are more lingually inclined in the posterior regions and labially inclined in the anterior area com-pared with the underlying roots. e mandibular rst premolar cusp tip is usually vertical to its root apex. e maxillary anterior teeth are the only segment in either arch that does not receive a long axis load to the tooth roots, but instead are usually loaded at a 12-degree angle. As such, their root diameter is greater than the mandibular anterior teeth. In all other regions the teeth are loaded perpendicular to the curves of Wilson or Spee. e ante-rior sextants may have labial undercuts that often mandate greater angulation of the implants or concurrent grafting of the site after insertion. e narrower width ridge often requires a root form implant design that is likewise narrower. Compared with larger diameters, smaller-diameter designs cause greater crestal stress and may not oer the same range of custom abutments. In addition, the narrower width of bone does not permit as much latitude in placement regarding angulation within the bone. is limits the acceptable angulation of bone in the narrow ridge to 20 degrees from the axis of the adjacent clinical crowns or a line perpendicu-lar to the occlusal plane.14 e angulation of available bone in the maxillary rst premolar region may place the adjacent cuspid at risk during implant placement. Esthetic RiskEspecially in the anterior region, extracting a tooth with the immediate implant placement may result in nonideal esthetic issues. erefore the patient should be evaluated preoperatively for the following esthetic parameters: lip line in relation to the AB• Fig. . Evaluation of Width: (A) Bone width may be measured on CBCT cross-section, (B) Evaluation by interactive treatment planning with implant placement.• Fig. . Cone beam computed tomographic three-dimensional axial image measuring the length between two root tips. 837CHAPTER 32 Immediate Implant Placement Surgical Protocolteeth and gingival margins, presence and position of interproximal papilla, shape and shade of adjacent teeth, presence of restorations on adjacent teeth, and a hard and soft tissue thickness analysis. In some cases, even with an ideal esthetic result, possible limitations may deem the placement of implants nonideal (Fig. 32.14). Type of Prosthesise clinician must always be proactive in the evaluation and anticipation of the nal prosthesis and its associated dimensions of crown height space, whether for a single-tooth crown or full-arch prosthesis. In clinical situations where tooth extraction will result in an edentulous arch, an alveoloplasty may need to be completed to satisfy the need for additional space. In completely edentulous patients, alveoplasty may result in the complete obliteration of the residual socket. is is imperative because sucient crown height space is needed for an overdenture and attachment, whereas minimal reduction is required when a type 3 xed prosthesis (FP-3) is treatment planned. When considering immediate implant placement for partially edentulous patients, the anatomic dimensions of the edentulous space must be evalu-ated. In some cases the opposing arch may need to be modied, or possible orthodontic treatment to realign or reposition the dentition (Fig. 32.15). Bone DensityBone quality or density refers to the internal structure of bone and reects a number of its biomechanical properties, such as strength and modulus of elasticity. e density of available bone in a potential implant site is a determining factor in treatment planning, implant design, surgical approach, healing time, and initial progressive bone loading during prosthetic reconstruction. e quality of bone is often dependent on the arch position. e densest bone is usually observed in the anterior mandible, with less dense bone in the anterior maxilla and posterior mandible, and the least dense bone typically found in the posterior maxilla. In addition to arch location, several authors have reported dier-ent failure rates related to the quality of the bone. Johns etal.15 reported a higher failure rate in the maxilla (poorer bone quality) in comparison with the mandible (more favorable bone density). Smedberg etal.16 reported a 36% failure rate in the poorest bone density. e reduced implant survival most often is more related to bone density than arch location. In a 15-year follow-up study, Herrmann etal.17 found implant failures were strongly correlated to patient factors, including bone quality, especially when cou-pled with poor bone volume. Bone quality is directly related to the ability to achieve an acceptable level of primary xation for • Fig. . Cone beam computed tomographic image determining ideal angulation.• Fig. . Maxillary lateral incisor resulting in poor esthetics because of a facially placed immediate implant placement.• Fig. . Immediate placement resulting in poor esthetics and periodon-tal complications because of positioning too deep and poor angulation. 838PART VI Implant Surgeryimmediate implant placement, as well as long-term success for all placement protocols (Fig. 32.16). Existing Crown FormWhen evaluating teeth for immediate placement, tapered crown forms usually are associated with a higher risk for soft tissue com-promise after extraction. e tapered crown also has more inter-proximal bone between the teeth and more facial bone over the tapered root. As such, under perfect conditions, the tapered tooth form may be more advantageous for extraction and immediate implant insertion. A square tooth form has less gingival shrinkage after extraction and exhibits less scalloping of the interproximal and facial bone with adjacent tooth roots. ere is also less bone between the roots and larger spaces between the extraction site and the implant. As a result an immediate implant insertion after extraction oers less benet for the soft tissue and greater risk for the implant-bone interface.18 Anatomic LocationFor immediate implant placement an awareness of the bone characteristics of the proposed anatomic location will help dic-tate the appropriate treatment plan modications for short- and long-term success. Regional variations in both available bone and bone density have already been described. e initial treatment plan before surgery suggests the anterior maxilla be treated as D3 bone, the posterior maxilla as D4 bone, the ante-rior mandible as D2 bone, and the posterior mandible as D3 bone. Bone remodeling, including loss of bone density, is pri-marily related to the length of time the region has been eden-tulous and therefore not loaded, the initial density of the bone, and mandibular exure and torsion.Immediate implant placement can take advantage of the fact that implant placement can be performed before the bone density in the jaws begins its usual decline after tooth loss. Tissue Thicknesse patient’s biotype is crucial in evaluating the susceptibility to increased tissue recession. Patients with a thin biotype are more predisposed to gingival recession and bone loss. Usually patients with a thin biotype will require bone and possible tissue grafting to minimize recession.Kan etal.19 reported marginal tissue levels around immediate implants may continue up to 8.2 years (mean 4 years) after place-ment. In addition, thin biotypes were found to recede three times more than thick biotypes. For patients exhibiting a thin biotype, the use of orthodontic forced eruption procedures before tooth removal and implantation. is will result in bone and soft tissues to move coronally, thereby increasing mucosal tissue adjacent to the implant (Fig. 32.17). Buccal Bone ThicknessIn general the buccal bone is thinner than the lingual bone, and the buccal bone is usually compromised after extraction. For example, Januario et al.20 evaluated facial bone thickness in the anterior maxillae at various measurements from the bone crest. ey deter-mined the bone thickness in the tooth sites to be approximately ≤1 mm thick (≤0.6 mm on average). In addition, they found the mar-ginal portion of the wall was <0.5 mm wide.20 After extraction, bone resorbs naturally from buccal to the lingual. ere exist three main sources of blood supply to the bone surrounding the teeth: the periodontal ligament blood vessels, the periosteal blood vessels, AB• Fig. . Poor Bone Quality. (A) D4 bone has an increased failure rate with immediate placement. (B) D4 bone has less than 30% bone-implant contact.• Fig. . Thin biotype leads to postoperative tissue recession and black triangles. 839CHAPTER 32 Immediate Implant Placement Surgical Protocoland the alveolar bone blood vessels. After an extraction, 20% of the blood supply from periodontal ligament blood vessels is lost and over the buccal plate of bone loses 50% of its blood supply.21 In addition, if a buccal ap is elevated on the buccal side, the peri-osteal blood supply will be discontinued for approximately 4 to 6 days, until the formation of a new anastomoses. e cortical bone buccal plate contains no endosteal blood vessels; therefore, com-plete resorption of the buccal plate may occur after extraction if implant placement or grafting is not completed. Socket grafting is frequently used in the treatment postextraction to prevent collapse and to minimize resorption of the thin buccal plate (Fig. 32.18). Implant Positione immediate implant positioning is dictated by the anatomic position. For implants placed in the maxillary anterior, immediate implants should not be placed close to the buccal plate; instead they should be positioned more in the lingual aspect of the extrac-tion socket. Evans and Chen22 evaluated the esthetic outcomes of immediate anterior implants and found implants placed more buccally had three times more soft tissue recession than lingually placed implants (1.8 versus 0.6 mm). Spray etal.23 reported that when 2 mm of facial bone thickness was present, vertical bone loss height was minimal. When <2 mm of bone thickness was present, tissue recession and failure resulted. In the mandibular anterior, implants should be positioned more toward the lingual, but not as much lingual version as the maxillary anterior. In the maxillary and mandibular posterior region the implants should be positioned in the center of the extraction socket, with a buccal lingual trajectory similar to the central fossas of the adjacent teeth. Requirements for Immediate Implant Placement 1. A CBCT evaluation conrms sucient bone quantity (buccal plate bone, bone apical to root apex, palatal bone); in addition, sucient proximal bone to avoid encroachment on adjacent roots 2. An esthetic risk evaluation should be completed before immedi-ate implant placement. e following factors should be taken into consideration (i.e., smile line, soft tissue drape, adjacent teeth shade stable and free of large restorations) 3. Ability to position implant in an ideal location for pros-thetic rehabilitation, which is dependent on the anatomic location and the available bone. 4. Ideal primary implant stability is achieved (35–45 N/cm), which is dictated by bone density, surgical technique (i.e., drill-ing and osseodensication protocols), and implant design 5. If any of the above requirements are not satisfactory, the clini-cian should determine if other treatment options exist. Immediate Implant Placement TechniqueStep 1: Clinical and Radiographic ExaminationA thorough clinical and radiographic examination should be completed as the rst step of the immediate placement technique. Preferably a comprehensive CBCT scan is taken of the associ-ated areas in question. e type of extraction defect (e.g., walls of bone present) may be anticipated with a careful preoperative clinical examination that includes periodontal probing, evaluation of mobility, infection, and fractures, along with two- and three-dimensional radiographs. ese collective clinical data are useful in evaluating for possible factors that would lead to immediate placement contraindications (Fig. 32.19). Step 2: Atraumatic Tooth ExtractionOnce the extraction of a natural tooth is indicated, methods to maintain or preserve the surrounding hard and soft tissues should be of utmost importance. Avoiding soft tissue injury reduces the dimensional loss of the underlying bone as the periosteum sup-plies more than 80% of the blood supply to surrounding cortical bone.24 e atraumatic extraction of a natural tooth should ide-ally begin with a sulcular incision, preferably with a thin scalpel blade or periotome 360 degrees around the tooth. is will ensure all connective tissue attachment bers above the bone level are severed. Failure to cut these bers before extraction will result in increased tissue trauma and possible fracture of the buccal plate of bone. For an atraumatic extraction, the less soft tissue reection the better as to minimize disruption of the blood supply.e next step in an atraumatic extraction process is to evaluate the crown and root anatomy for ease of removal, especially with multirooted teeth. Proximal reduction of the tooth will increase the space so bone expansion can be completed and also will pre-vent damage from the adjacent teeth. If the roots of the tooth to AB• Fig. . Buccal Bone Thickness. (A) Thin buccal bone leading to poor immediate implant candidate. (B) Postoperative radiograph depicting thick buccal bone, which results in higher success and better soft tissue healing. 840PART VI Implant Surgerybe extracted are divergent, they should be sectioned and removed as individual units, because this will decrease the risk of fracturing a root or the surrounding bone. Elevation from the mesiolingual, direct lingual, or distolingual is most benecial in avoiding the alteration of the buccal hard and soft tissue including the papillae.Periotomes and dental elevators, which both use the mechani-cal advantage of a wedge, can then be used to initiate the luxation of teeth for their removal. A traditional dental forceps is used to grasp the tooth for any needed additional luxation before tooth removal. Ideally forceps should not be used until mobility of the tooth is present. Alternatively, a biomechanically based forceps (physics forceps) can be used. Its increased mechanical advantage may allow for tooth removal without application of rotational forces, minimizing potential fracture of the facial plate of bone (Fig. 32.20).25 Step 3: Curetting the Extraction Sockete debridement of the extraction socket is imperative in the immediate implant process. Any remnants of periodontal liga-ment, bacteria, residual infection, dental material (i.e., gutta per-cha), and tooth fragments may aect the osseointegration process. erefore the extraction socket should be thoroughly debrided and irrigated with saline to ensure the socket is free of contaminants. A serrated spoon curette (Salvin Dental) should be used to scrape the walls of the socket (degranulation) and also initiate the regional acceleratory phenomenon (RAP), which enhances the healing pro-cess. is will initiate multiple areas of bleeding, which will pro-mote a greater initiation of angiogenesis to the area (Fig. 32.21). Step 4: Evaluating the Extraction Socket for Remaining Wallse easiest and simplest technique for evaluating the remaining walls of bone after an extraction is with a blunted probe. e index nger may be placed over the buccal plate of bone, and the probe is introduced into the socket and run up and down within the socket. If the probe is felt (i.e., most commonly on a missing buccal plate), then no bone is present and the socket is missing a wall of bone (Fig. 32.22).Classification of Bony DefectsThick Five-Bony-Wall Defects. e most ideal condition for a successful immediate implant is the presence of ve thick, bony walls around the extraction site. Most of the keys for predictable bone formation are present under these conditions, and the socket usually will form bone in the extraction socket without loss of width or height (Fig. 32.23). ABC D• Fig. . Cone Beam Computed Tomography (CBCT) Interactive Treatment Planning for Immedi-ate Implant. (A) CBCT cross section of maxillary central incisor. (B) Interactive treatment plan depicting implant length coinciding with root length. Placement of implant this length would lead to decreased prog-nosis. (C) Measurement of apical bone is available. (D) Ideal-length immediate implant. 841CHAPTER 32 Immediate Implant Placement Surgical ProtocolFour-Wall Bony Socket. When a labial plate around a socket is missing, the absence of the wall prevents space maintenance, reduces host bone vascularization, and is replaced with soft tissue. In most cases bone augmentation procedures must be used to obtain an ideal volume and contour of bone. Sockets with a missing wall are sig-nicantly compromised and heal by repair rather than regeneration.e rst determination after the tooth extraction is complete is the assessment of the thickness of labial and palatal plates of bone and their relative height to the ideal volume desired. When one of the plates of bone is thinner than 1.5 mm or when height is desired, a socket graft is indicated, even in the presence of ve bony walls (Fig. 32.24).ere exist three treatment options after tooth removal and bony wall evaluation: 1. No treatment: e most likely reason the option of no treat-ment would be chosen is if there is active infection present in the extraction site that cannot be completely eradicated. 2. Bone grafting: If the remaining walls of bone are not advan-tageous, then grafting the socket is completed. Usually one- to three-wall, and in many cases four wall defects should be grafted instead of attempting immediate placement. 3. Immediate implant placement: If favorable conditions exist, the implant is placed immediately after the extraction of the tooth. AB• Fig. . (A and B) Periotome atraumatic extraction; note minimal tissue reflection and damage.AB• Fig. . (A) Curetting the extraction socket with serrated spoon. (B) #10 round bur to remove soft tis-sue within the extraction socket and to initiate the regional acceleratory phenomenon technique. PART VI Implant SurgeryStep 5: Immediate Implant Placement TechniqueFlap Designree types of ap designs are used for immediate implants: open (buccal and lingual tissue reected), minimal ap (no buccal or lingual reection, but minimal ap to expose crestal area), or apless (tissue punch). Caneva etal.26 evaluated ap versus ap-less implant placement into extraction sockets and determined there is no dierence in bone loss between the two techniques (Fig. 32.25). Implant Osteotomye immediate implant placement surgical technique is initiated with either a surgical template or freehand technique. a. Surgical template: If a surgical template is used, it should be placed over the adjacent teeth (i.e., ideally tooth supported) and standard drilling procedures completed according to the manufacturer’s instructions (i.e., pilot, universal, fully guided surgical templates.) (Fig. 32.26). b. Freehand: e initial osteotomy is directly related to the ana-tomic area and remaining socket anatomy. For example, in the maxillary anterior region it is crucial to avoid placing the implant directly in the center of the extraction socket. Place-ment of the implant in this position may perforate the buccal plate and increase morbidity. In addition, the implant is often too facial, which compromises esthetics. It is imperative the implant’s nal trajectory is within the incisal edge.In the posterior regions, implants usually may be placed within the extraction site, along a trajectory in line with the central fossa of the adjacent teeth (Fig. 32.27 and Table 32.1).Heat generation. Site preparation should always be performed with copious amounts of irrigation with cold saline (i.e., refriger-ated) to reduce heat generation. It is often dicult to avoid heat generation when using a guided template or a apless procedure. erefore, a “bone dancing” technique should always be followed to allow saline to enter the osteotomy site. Prevention of perforation. During the osteotomy process for an immediate implant placement, the clinician should use their index nger over the buccal plate for tactile sense to conrm no buccal vibration or fenestration.27 Ideal PositioningIdeal depth. In general it has been accepted in the literature that 2 to 4 mm of bone is ideally required apical to the inferior part of the socket to obtain primary stability for an immediate implant.28 Madani etal.29 reported in a retrospective study that implant placement 1.08 mm subcrestally is the ideal depth of the neck of the implant. Subcrestal placement of the implant greater than 2 mm led to and increased bone loss. e vertical position of the implant shoulder should be 1 mm apical to the buccal crest to allow for adequate space for an emergence prole of the nal res-toration. Ideally a tapered design implant is used to avoid buccal fenestration, which is highly likely with a straight-walled design (Fig. 32.28).30,31 • Fig. . Evaluating the number of walls remaining with a colored peri-odontal probe. Note the lack of buccal plate.• Fig. . Four-Wall Extraction Socket (Mesial, Distal, Lingual, and Api-cal Present). The buccal plate is missing which is the most common wall to be lost after extraction.BMADL• Fig. . Five-Wall Extraction Socket (Mesial [M], Distal [D], Buccal [B], Lingual [L], and Apical [A] Present).842 ABC• Fig. . Flap Design. (A) Flapless. (B) Minimal flap. (C) Open flap is usually utilized when a wall of bone is missing and bone grafting is indicated.• Fig. . Surgical placement with cone beam computed tomography tooth-supported template into the immediate extraction site.• Fig. . Freehand Surgical Placement Into Immediate Extraction Site. 844PART VI Implant SurgeryJumping distance (maxillary anterior). e horizontal bone defect (“Jumping Distance,” “Gap”) is dened as the distance between the implant and the surrounding wall of the defect. Mul-tiple animal and human studies have shown that the gap will ll with bone, regardless of whether graft materials and barriers are used.32-35 Botticelli etal.33-35 reported that in defects of 2 mm or larger, no grafting was needed to grow bone. Tarnow etal.36 con-cluded that as long as the buccal plate is intact after the extraction, no bone graft, membrane, or primary closure is needed, irregard-less of how large the defect is. In most cases, care should be exer-cised not to completely ll the extraction socket with the implant. Many studies have shown conicting results with the aftermath of lling the void between the implant and buccal socket wall.26,37 In the author’s opinion, the gap should always be grafting with a bone substitute that will maintain the space long enough for bone to regenerate, which ultimately will maintain the hard and soft tissue. erefore a slower resorbing material (i.e., mineralized freeze-dried bone or xenograft), not a faster resorbing material (i.e., demineralized freeze-dried bone and autograft), should be used to augment the gap.Too large an implant diameter for the tooth in question should not be used because they will reduce the gap space, thereby risk-ing future soft and hard tissue recession (i.e. immediate implant placement in maxillary central incisor should not exceed 5 mm in diameter) (Fig. 32.29).38 In addition, if the diameter of the implant is too large, a compromised emergence prole will result with the nal prosthesis. Lindeman drill. In most extraction sites the standard round or starter drill will have a tendency to “chatter,” which makes initial placement of the osteotomy dicult. e author advocates the use of a Lindeman drill (side cutting surgical bur) to initiate osteoto-mies in extractions side. is type of bur when used in a “sawing” motion allows for an initial groove to be made that provides for proper and more precise positioning (Fig. 32.30). Maxillary anterior position. Multiple studies have shown that postoperative gingival recession in the anterior region is associ-ated with buccal implant positioning, which usually occurs when the implant is placed in the center of the extraction socket.22 In the most esthetic area of the oral cavity (maxillary anterior), it is imperative that the positioning of the implant be lingually ori-ented. is will allow the buccal gap to be >2 mm, which has been shown to be vital in preventing hard and soft tissue recession.39,40 A lingually placed implant will also minimize the possibility of apical perforation, which is common when implants are placed in the socket and a parallel walled implant is used.41 In addition, Surgical Protocol for Various Anatomic AreasAnatomic Area Initial Osteotomy Location Apical Implant positIoning Horizontal Implant Positioning MiscellaneousMaxillary anteriorEngagelingualplate Engage2–4mmofbonepastapexEngagemesial,distal,andpalatalNoengagementofbuccalwallMaxillary premolarFirst:palatalsocketSecond:lingualofsocketEngage2–4mmofbonepastapexEngagemesial,distal,andpalatalNoengagementofbuccalwallMaxillary molarsLateraltoseptalbonein“sawing”motionRarelycanengageapicallywithoutsinuspenetrationDifculttoobtainbecauseofsocketmorphologyUseextremecautionbecauserarelysufcientboneispresentMandibular anteriorCentertolingualofsocket Engage2–4mmofbonepastapexEngagemesial,distal,andpalatalAngulationandthinbuccalboneareofconcernMandibular premolarCentertolingualofsocket DifculttoengagemoreapicalbecauseofmentalforamenEngagemesial,distal,andpalatalUseextremecautionascloseproximitytomentalforamenMandibular molarsLateraltoseptalbonein“sawing”motionDifculttoengagemoreapicalbecauseofmandibularforamenDifculttoobtainbecauseofsocketmorphologyUseextremecautionascloseproximitytomandibularcanal TABLE 32.1AB• Fig. .  (A, B) Ideal depth to coincide with 2 to 3 mm below the free gingival margin. 845CHAPTER 32 Immediate Implant Placement Surgical Protocoloversize implants should not be placed in the maxillary anterior because the buccal gap will be obliterated and the implant will encroach on the proximal area.42 If the proximal area is compro-mised, a poor emergence prole will result, which may lead to peri-implant disease (Fig. 32.31). Minimum torque. To achieve primary stability, a minimum torque value has been shown to be one of the most important factors in the success of immediate implants. e minimum torque has been shown to be approximately 35-45 N/cm in the literature.43,44 Final Emergence Position Based on Prosthesis. For a cement-retained prosthesis, the implant should exit slightly lingual to the incisal edge in the anterior and in the central fossa in the posterior. For a screw-retained prosthesis, the implant should exit in the cingu-lum area in the anterior and in the central fossa of the posterior. For a removable prosthesis, the implants should exit slightly lingual to the anterior teeth and within the central fossa of the posterior teeth. Implant DesignTapered versus parallel. Many studies have evaluated the implant design (tapered versus parallel) in the immediate implant protocol. McAllister etal.45 showed a high success with tapered implants with a high initial implant stability. Tapered implants have been reported to be superior with immediate implants because the implants are narrow apically, which result in less chance of perforation. Because they are wider coronally, their jumping distance is less, therefore requiring less augmentation. However, Lang etal.46 found that parallel and tapered implants have very positive short-term success rates with improved wound healing and primary stability. Implant surface. Many researchers have evaluated rough versus machined surfaces for immediate implants. Wagenberg and Froum47 ADBC• Fig. . (A) Lindeman side-cutting drill (Salvin). (B) As a guide for depth preparation, measure the flutes of the drill (i.e. use this measurement as a depth guide for osteotomy preparation, (C) Extracted tooth may be measured to determine socket depth, (D) Lindeman bur initiating the osteotomy.• Fig. . Jumping Gap Present on Facial of Implant. 846PART VI Implant Surgerycompleted a clinical study with 1925 implants and reported higher success rates with roughened surfaces. Results concluded machined-surface implants were twice as likely to fail as roughened surface implants (4.6% versus 2.3%). In addition, studies have veried that roughened surfaces with a microthreaded neck result in less crestal bone loss than implants with non-microthreaded necks.48 Implant neck/collar design. When evaluating the implant col-lar or neck of the implant to be placed in an immediate extracting site, studies have shown a tapered platform-switched internal connection to be superior for healing and implant survival.49-52 Linkevicius etal.53 determined that the use of a platform switch-ing implant in a one-stage implant placement approach does not prevent crestal bone loss when the tissue is thin (≤2 mm). How-ever, when the tissue is thick (>2 mm), use of a platform-switch implant shows minimal bone recession at the 1-year time frame.53 Puisys and Linkevicius,54 in a two-stage protocol, showed similar results with the thin versus thick tissue. in tissues (≤2 mm) lost minimal amount of crestal bone, whereas thick tissues (>2 mm) or thin tissues augmented with acellular dermal matrix (LifeNet; Salvin) had similar crestal bone maintenance with minimal bone loss at 1 year postoperatively (Fig. 32.32).54 Implant length. Schnitman et al.55 reported that implant lengths greater than 10 mm provide signicantly higher suc-cess rates for immediate implants. However, the implant length is directly related to the bone density. In favorable bone densi-ties (e.g., D1, D2), implant length is not as important. When poor bone density is present (e.g., D3, D4), longer implants are required because of the greater need for primary stability and rigid xation (Fig. 32.33 and Box 32.3). Implant Stabilitye initial stability of the immediate implant is one of the most critical factors in the success of the implant. When micromove-ment occurs, the implant-bone interface is reduced, thereby resulting in loss of primary stability. Micromovement greater than 100 μm may cause brous encapsulation of the implant.56 ere exist two types of implant stability, primary and secondary.Primary. Primary stability is dened as the stability of the dental implant immediately after placement; it is derived from mechanical friction of the implant threads and the surrounding bone. Several methods have been advocated in the literature to determine primary stability. a. Percussion is the rst test method in the literature to be used to assess primary stability and estimate the amount of bone-implant contact. is technique is based on vibrational-acoustic science, where a “high pitched” sound signies integration and a “low-pitched” sound may be indicative of lack of integration. ABC• Fig. . Maxillary Anterior Placement. (A) Osteotomy should be initiated within the lingual wall. (B) A groove is placed in the lingual wall. (C) From the lingual groove position, the handpiece is rotated facially to allow for ideal implant angulation.• Fig. . Tapered and platform switch implant has been shown to be the ideal implant for immediate implants. 847CHAPTER 32 Immediate Implant Placement Surgical ProtocolUnfortunately, this test is highly dependent on the clinician’s experience level and subjective beliefs. erefore although still used, it is not the most ideal testing method (Fig. 32.34).57,58 b. Periotest (Seimens, Bensheim, Germany) is a testing method that has been proposed to be a more objective method for assessment of implant stability. Although much better than the percussion test, the Periotest has been shown to have inaccura-cies in the lack of resolution, poor sensitivity, and subject to operator variability (Fig. 32.35).59 c. A more recent method is the use of insertion torque that can be measured with low-speed insertion tools (i.e., surgical hand-piece) or manual wrench ratchet. It has been shown that for a successful immediate loading protocol, the insertion torque should be between 35 and 45 N/cm.60,61 d. Resonance frequency analysis (RFA) is a diagnostic tool that allows for detecting implant stability as a function of the stiness of the bone-implant interface. is test can be used in a continuous and objective manner during the healing phases of the implant. RFA was initially presented by Meredith etal.62 in 1996. RFA has been shown to have quantitative and reproducible measurements on the presence of integration, immediate load feasibility, and follow-up evaluation at the prediction of an implant failure.63RFA is a technique that is based on continual excitation of the implant interface through the use of dynamic vibration anal-ysis (piezo eect). A specialized transducer, which contains two MaxillaryCentralincisor:13.0mmLateralincisor:13.0mmCanine:17.0mmFirstpremolar:14.0mmSecondpremolar:14.0mmFirstmolar:12.0mm(B),13.0mm(L)Secondmolar:11.0mm(B),12.0mm(L) MandibleCentralincisor:12.5mmLateralincisor:14.0mmCanine:16.0mmFirstpremolar:14.0mmSecondpremolar:14.5mmFirstmolar:14.0mmSecondmolar:13.0mmB, Buccal; L, lingual. • BOX 32.3 Root Lengths20• Fig. . Percussion test may be used to evaluate the initial primary stability; however, this test is very subjective.• Fig. . Periotest was a more objective test to evaluate initial stability; however, it gives inconsistent results.• Fig. . Implant Length. Ideally an immediate implant needs to extend 2 to 4 mm beyond the apex of the tooth root, especially when poor bone density is present. 848PART VI Implant Surgerypiezoceramic elements, is either attached directly to the implant or abutment. e rst piezo element generates an excitation sig-nal that is a sinusoidal wave (5–15 kHz), leading to vibration of a whole transducer-implant-tissue complex. e oscillation response is measured by the second piezo element.64e RFA technique measures implant stability as a function of stiness of the bone-implant complex. e health of the implant is measured on an implant stability quotient (ISQ) that is calcu-lated on a scale from 1 to 100. e full integration of an implant is usually measured in the range from 45 to 85 ISQ. Measurements of less than 45 are indicative of implant failure, whereas an ISQ value of 60 to 70 indicates success.65 Secondary. During the healing process, the primary stability process is replaced by the biological process of bone healing. e main factors that inuence secondary stability are the initial pri-mary stability, bone remodeling process, bone-implant contact, and implant surface characteristics.e use of RFA after the initial healing has shown great success. Han etal.66 reported a decrease in ISQ values within the rst 3 weeks after implant placement; then a return to the original ISQ values is observed approximately 8 weeks after surgery.When comparing implants placed into immediate extrac-tion sites vs. healed sites, Han et al.67 showed implants immediately loaded performed the same, whether in postex-traction or healed sited. In addition, they showed that tapered implants with strong self- cutting threads provides an excel-lent initial stability, with high insertion torque and ISQ values (Fig. 32.36). Grafting/MembraneAfter implant stability is conrmed, the present osseous defects are evaluated and grafted accordingly. Ideally the bone-grafting mate-rial should include a slower resorbing material that will maintain the space to allow for bone regeneration (e.g., demineralized/mineralized allograft, allograft + autograft, or xenograft). e membrane selection is dictated by the defect present. If the buccal wall is missing or very thin, then a longer-acting collagen membrane is recommended. It is more predictable if the membrane is placed on the buccal along with grafting before implant placement. If all ve walls are present, then a collagen plug (or collagen tape) is placed over the socket (Fig. 32.37). ClosureIn most immediate placement sites it is dicult to obtain primary closure unless the ap is advanced. However, advancement of the ap will result in less keratinized tissue to the facial of the pros-thesis. When inadequate keratinized tissue results, tissue grafts are usually indicated (Fig. 32.38). Immediate Load or Staged TreatmentAfter implant placement a healing abutment (1-stage) or a cover screw (2-stage) may be placed. In immediate load cases a provisional restoration may be inserted, allowing the pontic (ovate design) to heal the soft tissue. De Rouck etal.68 demonstrated that using sin-gle immediate implants with immediate provisionalization aids in • Fig. . Resonance Frequency Analysis (RFA). The Penguin RFA (Glidewell) is a noninvasive resonance frequency analysis test that results in reliable, accurate numerical results concerning the stability of immediate placed implants.AB• Fig. . (A) Grafting of the jumping gap and other bony defects. (B) Membrane placement to prevent migration of bone graft material.• Fig. . Closure. Usually primary closure is not completed, and extending the flap to obtain primary closure is not generally recommended. 849CHAPTER 32 Immediate Implant Placement Surgical Protocoloptimizing the esthetic results. ey concluded that the provisional will mold the soft tissue and will limit the amount of soft tissue loss. Tarnow etal.69 reported that immediate implant placement with a bone graft and a well-contoured provisional crown resulted in the least amount of facial-palatal contour change (<1 mm). Immediate Implants Into Infected SitesPlacing implants into infected sites has been controversial. Villa and Rangert70 reported on a series of cases where implants were placed immediately after extraction and had exhibited periodon-tal or endodontic infections. After 2 years the cumulative sur-vival rate was 100%. e theory includes that after extraction, infections and microorganisms present can be eliminated with proper socket degranulation. Novaes etal.71 evaluated immediate implant placement of implants placed in chronically infected sites. ey determined that as long as antibiotics are used, meticulous debridement is completed, and alveolar bone preparation before implant placement is properly performed, immediate implants in infected sites are not contraindicated. Crespi etal.72 evaluated immediate implant associated with a chronic periapical lesion; they did not demonstrate an increased rate of complications, and showed favorable soft and hard tissue postoperatively (Fig. 32.39). ComplicationsNot Recognizing 4-Wall SocketOne of the most common complications for immediate implant placement is for the clinician to not diagnosis the loss of the buccal socket wall. A ve wall socket is ideal and is treated with the con-ventional surgical technique (Fig. 32.40). In contrast, a four-wall socket requires a longer acting collagen membrane that is positioned over the buccal aspect of the extraction site. (Fig. 32.41).Not Understanding Specific Anatomical FactorsEach tooth in the maxillary and mandibular arch is associated with factors which may make conditions ideal for an immediate implant placement or contraindicate placement. e author has formulated a protocol for each tooth based on specic anatomic and treatment planning criteria. Each speciifc tooth has ideal con-ditions (green), cautious conditions (yellow), or contraindication (red). (Fig. 32.42 and Fig. 32.43). Inability to Obtain Primary StabilityPrimary implant stability may be dicult to achieve in extraction sites where the trabecular bone density is less than ideal. Unlike a healed ridge of desirable bone volume, primary stability in fresh extraction sites is more dicult to achieve in general because of the lesser quantity of native bone present, as well as the fact that the anatomic challenge of the coronal aspect of the extraction site is often wider than the implant being placed. Potential variations in bone density may necessitate multiple modications to osteot-omy preparation and implant placement protocols compared with procedures performed in homogeneous bone density. As a result, after attempted implantation, the clinician may be faced with an implant with a questionable level of primary stability (Fig. 32.44).PreventionComplete Osteotomy Preparation in Appropriate Location and Surgical Sequence. Depending on the size of the extracted tooth and the implant to be placed, the implant in most cases extend past the original dimensions of the root apex and pro-vide mechanical retention of the implant. In the anterior max-illary region, immediate implant placement often requires the osteotomy and implant insertion engage the lingual wall of the alveolus for rigid xation. For maxillary posterior teeth the initial bur should be positioned o-center toward the lingual side of the interradicular septum. For mandibular posterior teeth the initial bur should be positioned on the mesial aspect of the interradicular septum. A Lindemann bur is useful for initiating and modifying osteotomies. e objective of this multiplane preparation process is to create an osteotomy in a prosthetically correct position with-out compromising the buccal wall of bone. Underprepare Osteotomy Width and Overprepare Oste-otomy Length. Misch14 initially outlined a protocol that adapts the treatment plan, implant selection, surgical approach, healing regimen, and initial prosthetic loading to all bone densities and all arch positions, which resulted in similar implant success for all bone densities. e density of the residual native bone can inuence the ability to achieve adequate primary xation. With anterior single-rooted teeth, using bone beyond the apex and the lateral engagement of some or all of the tooth socket walls is instrumental in obtaining sucient primary stability. With AB• Fig. . (A and B) Extreme caution should be exercised when placing immediate implants into sites with active infection. 850PART VI Implant Surgeryposterior implants, vital structures such as the inferior alveolar nerve and the maxillary sinus limit stability derived from bone beyond the tooth apices. Furthermore, the limited native bone present undergoes remodeling after the surgical trauma of oste-otomy preparation and implant insertion. is trauma leads to a weakening of the bone-implant interface and may have an adverse eect on the initial implant stability (Fig. 32.45).Often inadequate primary stability may manifest itself only after 4 to 6 weeks; the bone interface is stronger on the day of implant placement compared with 3 months later. e surgical process of the implant osteotomy preparation and implant inser-tion cause a RAP of bone repair around the implant interface. As a result of the surgical placement, organized, mineralized lamellar bone in the preparation site becomes unorganized, less mineral-ized, woven bone of repair next to the implant. e implant-bone interface is weakest and most at risk for overload at 3 to 6 weeks after surgical insertion because the surgical trauma causes bone remodeling at the interface that is least mineralized and unorga-nized during this time frame. A clinical report by Buchs etal.73 found immediately loaded implant failure occurred primarily between 3 and 5 weeks after implant insertion from mobility without infection. At 4 months the bone is still only 60% miner-alized, organized lamellar bone. With time, bone formation and mineralization will lead to increased interlocking with the implant surface and a stronger implant-bone interface. However, this has proved to be sucient in most bone types and clinical situations ABCDEFGH• Fig. . Five Wall Socket Immediate Implant Placement. (A) Maxillary second premolar depicting sufficient apical bone for immediate implant placement. (B) Atraumatic extraction with a periotome. (C) Mobile root removed with forceps. (D) Five-wall socket remaining after extraction. (E) Osteotomy initiated with Lindeman drill slightly lingual. (F) Bone chips from bur flutes is saved for grafting the buccal gap after implant placement. (G) Osteotomy diameter is increased. (H) Implant insertion with handpiece. (I) Final implant positioning. 851CHAPTER 32 Immediate Implant Placement Surgical Protocolfor two-stage healing and delayed implant loading. e relative lack of native bone (compared with a healed site) suggests the osteotomy should frequently be undersized in width, the degree of which is dependent on bone density. In addition, for less dense bone, immediate implant xation can be facilitated if the clini-cian can use osteotomes or osseodensication techniques for radial compaction. Dependent on tooth socket size and anatomy, suf-cient implant stability can sometimes be achieved by lateral wall engagement only. However, extending the osteotomy 2 to 4 mm past the socket apex (without encroaching on vital structures) is more commonly completed for primary stability.74 Implant Design and Initial Stability. e clinical perception of primary implant stability is frequently based on the cutting resis-tance of the implant during its insertion. e feeling of “good” sta-bility may be accentuated if there is the sense of an abrupt stop at the seating of the implant. Although root form tapered implants often have a geometry that will provide a rm stop, the resultant sta-bility may be a false perception.75 In addition, in a tapered, threaded implant, threads at the apical half are often not as deep because the outer diameter of the implant body continues to decrease. is limits the initial xation of the implant and further reduces the functional surface area. For immediate implant placement, the tapered/conical body design may be of benet during initial inser-tion because it is positioned within the osteotomy halfway before engaging bone. e choice of implant body with regard to primary stabilization is equivocal and may be more inuenced by osteotomy preparation than implant body design. A study by Sakoh etal.76 concluded that the combination of both conical implant design and the procedure of under dimensioned drilling appeared to be associ-ated with increased primary stability (Fig. 32.46). Treatment OptionsRedirection dependent on bone density. If the implant has poor primary stability, the implant can sometimes be redirected into denser bone; the redirection may be needed in more than one plane and kept within the ideal three-dimensional boundaries for prosthetic reconstruction. Often a subtle tap of the (threaded) implant in an axial direction will gain the needed initial primary stability without putting the implant at risk from excessive apical positioning relative to the osseous crest and any adjacent teeth. A mallet and straight or oset osteotome can be used over top of the implant body. Use of larger diameter implant. e dimensions, longer and/or wider, of the “rescue” implant may allow for satisfactory better primary xation; however, it must still be in an acceptable posi-tion in relation to the crestal bone, adjacent teeth, and planned nal prosthesis.77 is may be placed in a redirected manner described earlier. An increased implant surface area can engage more cortical bone. It has also been shown in an experimental study in rabbit tibia that wider implant diameters resulted in increased removal torque values.78 Matsushita etal.79 used a two-dimensional nite element method to analyze the eect of dier-ent implant diameters on stress distribution within the alveolar bone using HA-coated implants. ey found that stress in cortical bone decreased with increased implant diameter. Ivano etal.,80 however, reported a lower survival rate and a tendency for higher bone loss for 5.0-mm-diameter implants, compared with 3.75-mm- or 4.0-mm-diameter implants. Resultant decreased facial bone dimensions associated with wider implant dimensions increase the probability of soft tissue recession. However, caution should be exercised in placing too wide of an implant because it IJKL M N• Fig. ., cont’d (J) Cover screw or healing abutment should be placed before bone graft placement. (K) Bone graft is used to fill the jumping gap and any bony defects; amalgam plugger allows for easy place-ment into small voids. (L) Grafting material packed into voids and membrane placement. (M) Final closure. (N) Final radiograph. 852PART VI Implant Surgerymay encroach on the buccal plate or result in a nonideal prosthetic outcome. Leave implant in place. An implant with loss of rotational sta-bility (spinner) and minimal, if any, surrounding ridge deciencies may be left in place. If replacement is not possible (e.g., in cases of inadequate bone dimensions or where a larger implant is unavail-able), the implant clinician must then decide whether to leave the implant in place or remove it and reevaluate the site for further implant therapy after healing is complete. Ivano etal.81 reported osseointegrated implants that have been mobilized because of a traumatic disruption of the bone-implant interface may reinte-grate if allowed to heal for an additional period. Orenstein etal.82 reported a 79.8% survival rate after 3 years of implants that were mobile at placement. A signicant factor for most of these implants was the presence of a HA coating. Almost half of the noncoated, initially mobile implants failed by 3 years postplacement. Even if initially mobile implants are found to integrate, precautions are advised to avoid implant overload. Clinicians may want to use strategies such as long-term temporization to promote bone matu-ration and evaluate the viability of initially mobile implants in function before inserting the denitive prosthesis. Abort the procedure. e clinician may consider aborting the procedure and proceeding with bone grafting and delayed implant placement (Fig. 32.47). A B CD E FGH I• Fig. . Four-Walled Socket Immediate Implant Placement. (A) Maxillary left lateral incisor cone beam computed tomography showing no buccal bone present. (B) Sulcular and broad-based release inci-sions. (C) Reflection. (D) Lack of buccal bone remaining and evaluation of the 2- to 4-mm measurement from the free gingival margin. (E) Atraumatic extraction. (F) Root removal. (G) Osteotomy with Lindeman drill in lingual wall. (H) Extended collagen membrane measurement. (I) Collagen cut with scalpel to fill socket. 853CHAPTER 32 Immediate Implant Placement Surgical ProtocolKLMNJ• Fig. ., cont’d (J) Positioning of collagen along buccal wall. (K) Implant placement. (L) Abutment placement to check angulation. (M) platelet rich fibrin (PRF) placed underneath the flap. (N) Final closure.Postoperative ComplicationsTransitional Prosthesis Impingemente transitional prosthesis over an immediate implant should not rest or apply pressure to the soft tissue over the site. Implants and particulate grafts are more prone to movement during healing, which prevents blood vessels from entering and forming bone in the site. If possible, a xed provisional or a pressure-free prosthesis is ideal for successful healing (Fig. 32.48). Neurosensory Impairmente close proximity of inferior alveolar nerve to the apices of the man-dibular posterior teeth poses the possibility of neurosensory impair-ment when preparing osteotomies and during implant insertion. In most cases, the immediate implant gains its primary stability from the bone beyond the root apices. is risk is greater in the posterior man-dible extraction site than in a healed site with its increased volume of bone and associated likelihood of the more abundant bone achieving primary stability without nerve encroachment. Preventive strategies include preoperative three-dimensional imaging, guided surgery, and having a heightened awareness of local anatomy (Fig. 32.49). Neuro-sensory impairment is most common in Type 1 nerve positions (i.e. anterior posterior position close to root apexes. For this discussion, care must be taken to distinguish between a compromise(s) that could be present after a delayed/two-stage pro-cedure (e.g., increased nal crown height) versus a compromise that could be solely attributed to implant placement at the time of extrac-tion. Examples of the latter are characterized by excessive positions in one or more of the potential three reference planes. Nonideal posi-tioning can also result after multistage procedures; however, the need for native bone for primary stability in immediate placement cases increases the likelihood of positioning error. Management of cases with resultant excessive mesial-distal space/length can be frequently treated by placement of additional (usually narrower-diameter) implants. Use of surgical templates or guided surgery are recom-mended for clinicians desiring physical reference points during sur-gery (Fig. 32.50).ConclusionPlacement of immediate implants into an extraction site has been shown through the literature to be very successful. Technologi-cal advances have led to an array of options for the patient and clinician as an alternative to the traditional two-stage technique. Immediate placement implants pose many challenges to clini-cians, especially when treating patients with preexisting hard and soft tissue deciencies. In this chapter, the advantages and dis-advantages of immediate implants were explained in detail along with numerous treatment planning factors that should be ideally evaluated prior to treatment. With appropriate patient selection and treatment planning, complications may be minimized, and success rates increased with immediate placement implants. In addition, each specic tooth position is discussed in detail with a treatment planning protocol which allows the clinician to under-stand when ideal conditions exist, cautious variables are present, and when immediate placement is contraindicated. 854PART VI Implant SurgeryIDEAL CAUTION HIGH RISK IDEAL CAUTION HIGH RISK IDEAL CAUTION HIGH RISKAvailable Bone Height>4mm below nasal floor2-3 mm below nasal floor< 2mm below nasal floor>4mm below nasal floor2 -3 mm below nasal floor< 2mm below nasal floor>4mm below nasal floor2-3 mm below nasal floor< 2mm below nasal floorAvailable Bone Width> 7mm 6mm < 6mm > 6mm 5 mm < 5mm > 7mm 6 mm < 6 mmSmile LinePositionLow Medium High Low Medium High Low Medium HighEsthetic DemandsNone Minimal High None Minimal High None Minimal HighGingival Index Favorable Unfavorable Favorable Unfavorable Favorable UnfavorableVertical Bone LossNone PresentMinimal SignificantNone PresentMinimal SignificantNone PresentMinimal SignificantFacial Bone ConcavityNone Minimal Significant None Minimal Significant None Minimal SignificantMesial Distal Space8.0 mm 7.0 -8.0 mm < 7mm > 6.0 mm 5.0 –6.0 mm < 5.0 mm 8.0 mm 7.0 –8.0 mm < 7.0 mmNasopalatine Canal PositionSmall Medium Large N/A N/A N/A N/A N/A N/AOcclusal RelationshipNot PresentModerate DeepbiteSignificant DeepbiteNot presentModerate DeepbiteSignificant DeepbiteNot PresentModerate DeepbiteSignificant DeepbiteBone Density D2 D3 D4 D2 D3 D4 D2 D3 D4Ideal Implant Size4.0 - 4.5 mm 4.0 – 4.5 mm 4.0– 4.5 mm 4.0 - 4.5 mm 4.0 –4.5 mm 4.0– 4.5 mm 4.0 -4.5 mm 4.0– 4.5 mm 4.0– 4.5 mmMaxillary Central Maxillary Lateral Maxillary CuspidIDEAL CAUTION HIGH RISK IDEAL CAUTION HIGH RISK IDEAL CAUTION HIGH RISKAvailable Bone Height>4mm above root apex2-3 mm above root apex< 2mm above root apex>4mm above root apex2-3 mm above root apex< 2mm above root apex< 4 mm above root apex2-3 mm above root apex< 2mm above root apexAvailable Bone Width> 7 mm 6 mm < 6 mm > 7 mm 6 mm < 6 mm > 8mm 7mm < 7mmSmile Line Low Medium High Low Medium High Low Medium HighEsthetic DemandsNone Minimal High None Minimal High None Minimal HighGingival Index Favorable Unfavorable Favorable Unfavorable Favorable UnfavorableVertical Bone LossNone Minimal Significant None Minimal Significant None Present Minimal SignificantMaxillary Sinus PositionPosterior to 1stPremolar ApexApex within 1-2 mm of sinus< 1mm apex to sinus> 4 mm beyond apex2 –3 mm beyond apex< 1 mm apex to sinus> 4 mm beyond apex2 –3 mm beyond apex< 1 mm apex to sinusMesial Distal Space7.0 mm 6.0 mm < 6.0 mm 7.0 mm 6.0 mm < 6.0 mm11.0 mm9 - 11.0 mm < 9.0 mmBone Density D2 D3 D4 D2 D3 D4 D2 D3 D4Ideal Implant Size4.0 -5.0 mm 4.0 -5.0 mm 4.0 -5.0 mm4.0 -5.0 mm 4.0 - 5.0 mm 4.0 - 5.0 mm5.0 –6.0 mm 5.0 – 6.0 mm 5.0 – 6.0 mmMaxillary 1stPremolar Maxillary 2ndPremolar Maxillary 1st/2ndMolarAB• Fig. . Maxillary Immediate Implant Treatment Factors: (A) Maxillary Anterior, (B) Maxillary Posterior. 855CHAPTER 32 Immediate Implant Placement Surgical ProtocolIDEAL CAUTION HIGH RISK IDEAL CAUTION HIGH RISK IDEAL CAUTION HIGH RISKAvailable Bone Height> 4mm beyondroot apex2-3 mm beyond root apex<2mm beyond root apex> 4mm beyondroot apex2-3 mm beyond root apex<2mm beyond root apex> 4mm beyondroot apex2-3mm beyond root apex<2mm beyond root apexAvailable Bone Width> 6 mm 5 mm < 5 mm > 6mm 5 mm < 5mm > 7 mm 6 mm < 6 mmEsthetic DemandsNone Minimal High None Minimal High None Minimal HighGingival Index Favorable Unfavorable Favorable Unfavorable Favorable UnfavorableVertical Bone LossNone Minimal Significant None Minimal Significant None Minimal SignificantFacial Bone ConcavityNone Minimal Significant None Minimal Significant None Minimal SignificantMesial Distal Space5.0 – 6.0 mm4.5 – 5.0 mm < 4.5 mm 5.0 – 6.0 mm 4.5 – 5.0 mm < 4.5 mm 7.0 mm 6.0 – 7.0 < 6.0 mmBone Density D2 D3 D4 D2 D3 D4 D2 D3 D4Ideal Implant Size3.0 – 3.5 mm 3.0 – 3.5 mm 3.0 –3.5 mm 3.0 – 3.5 mm 3.0 – 3.5 mm 3.0 –3.5 mm 4.0 – 4.5 mm 4.0 – 4.5 mm 4.0 –4.5 mmMandibular Central MandibularLateral Mandibular CuspidIDEAL CAUTION HIGH RISK IDEAL CAUTION HIGH RISK IDEAL CAUTION HIGH RISKAvailable Bone Height> 4mm beyondroot apex2-3 mm beyond root apex<2mm beyond root apex> 4mm beyondroot apex2-3 mm beyond root apex<2mm beyond root apex> 4mm beyondroot apex2-3mm beyond root apex<2mm beyond root apexAvailable Bone Width> 7 mm 6 mm < 6 mm > 7 mm 6 mm < 6 mm > 8 mm 7 mm < 7 mmForamen/Canal Location> 4mm below apex2- 4mm below apex< 2mm below apex> 4mm below apex2- 4mm below apex< 2mm below apex> 4mm below apex2- 4mm below apex< 2mm below apexGingival Index Favorable Unfavorable Favorable Unfavorable Favorable UnfavorableVertical Bone LossNone Minimal Significant None Minimal Significant None Minimal SignificantMesial Distal Space7.0 mm6.0-7.0 mm < 6.0 mm 7.0 mm 6.0-7.0 mm < 6.0 mm 11.0 mm 9 - 11.0 mm < 9.0 mmBone Density D2 D3 D4 D2 D3 D4 D2 D3 D4Ideal Implant Size4.0 – 5.0 mm 4.0 – 5.0 mm 4.0 – 5.0 mm 4.0 – 5.0 mm 4.0 – 5.0 mm 4.0 – 5.0 mm 5.0 – 6.0 mm 5.0 – 6.0 mm 5.0 –6.0 mmMandibular 1stPremolar Mandibular 2ndPremolar Mandibular 1st/2ndMolars AB• Fig. . Maxillary Immediate Implant Treatment Factors: (A) Mandibular Anterior, (B) Mandibular Posterior. 856PART VI Implant Surgery• Fig. . Immediate Implant Complication. Lack of primary stability that increases complication and failure rate.AB• Fig. . (A) The trajectory should not be dictated on the natural tooth because this may be misleading. (B) Ideal trajectory based on host bone.• Fig. . Tapered implants have been shown to have better immediate implant fixation.• Fig. . Implant with inadequate primary stability and minimal adja-cent host bone. If adequate primary stability cannot be obtained, the implant should be removed and the site grafted. 857CHAPTER 32 Immediate Implant Placement Surgical ProtocolAB• Fig. . Transitional Prosthesis Impingement. (A) Essix appliance. (B) Insertion of Essix appliance depicting no pressure on surgical site.• Fig. . Neurosensory Impairment resulting from immediate implant placement too deep which penetrated the mandibular canal.• Fig. . Management of malpositioning error by addition of narrow implant. (From Jividen GJ, Misch CE. Complications associated with imme-diate implant placement. 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