Optimal Tooth Preparation with Different Tooth Reduction Guides: Case Presentation
chine (Pro-Vac, Vacuum Formers). It was placed on the an-
terior teeth to evaluate overall tooth preparation. Then it
was perforated with a diamond bur (6 HP Round 51 mm
Overall Shank 2, Brasseler) in speciﬁc zones in order to
insert the periodontal probe (CP-15 UNC color-coded
single end probe, Hu-Friedy Qulix) to take measurements
(Fig 6). Moreover, putty matrix guides (Platinum 85, Zher-
mack) were fabricated and used to evaluate incisal and
two-plane reduction. The ﬁnal space available for the fu-
ture ceramic restorations was 0.75 mm on facial and 1.5
mm on incisal surfaces (Figs 7a and 7b). Crown tooth
preparation for the right lateral incisor was reﬁned prior to
Final Impression and Fabrication of
The ﬁnal impression was made using the double-cord
technique, ﬁrst placing #000 cord followed by #0 cord on
teeth with veneer preparation and #00 cord followed by
#1 cord for the crown preparation (Retraction Cord Plain
Knitted, Ultrapak) (Figs 8a and 8b). Impression trays (Rim-
Lock Impression Trays, Dentsply Caulk) were loaded with
PVS in heavy-body and light-body consistency (Virtual
380, Ivoclar Vivadent) and ﬁnal impressions made (Fig 9).
The ﬁnal master cast was fabricated in type IV stone (Fuji-
rock, GC America). Refractory feldspathic porcelain veneers
Figs 8a and 8b Double-cord
Fig 9 Final impression.
JURADO ET AL
were fabricated (Noritake Super Porcelain EX-3, Kuraray
Dental) and the full-coverage crown was made of press-
able feldspathic (Ex-3 Press, Kuraray Noritake (Figs 10a
to 10e). Line angles were carefully deﬁned during the ﬁn-
ishing of the ceramic veneers (Figs 11a and 11b).
Figs 10a to 10e (a) Master cast and alveolar dies for (b to e) fabrication of feldspathic veneers.
Figs 11a and 11b
(a) Deﬁning line angles and ﬁnishing of (b) ﬁnal feldspathic veneers.
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Optimal Tooth Preparation with Different Tooth Reduction Guides: Case Presentation QDT 2020201chine (Pro-Vac, Vacuum Formers). It was placed on the an-terior teeth to evaluate overall tooth preparation. Then it was perforated with a diamond bur (6 HP Round 51 mm Overall Shank 2, Brasseler) in speciﬁc zones in order to insert the periodontal probe (CP-15 UNC color-coded single end probe, Hu-Friedy Qulix) to take measurements (Fig 6). Moreover, putty matrix guides (Platinum 85, Zher-mack) were fabricated and used to evaluate incisal and two-plane reduction. The ﬁnal space available for the fu-ture ceramic restorations was 0.75 mm on facial and 1.5 mm on incisal surfaces (Figs 7a and 7b). Crown tooth preparation for the right lateral incisor was reﬁned prior to ﬁnal impression.Final Impression and Fabrication of RestorationsThe ﬁnal impression was made using the double-cord technique, ﬁrst placing #000 cord followed by #0 cord on teeth with veneer preparation and #00 cord followed by #1 cord for the crown preparation (Retraction Cord Plain Knitted, Ultrapak) (Figs 8a and 8b). Impression trays (Rim-Lock Impression Trays, Dentsply Caulk) were loaded with PVS in heavy-body and light-body consistency (Virtual 380, Ivoclar Vivadent) and ﬁnal impressions made (Fig 9). The ﬁnal master cast was fabricated in type IV stone (Fuji-rock, GC America). Refractory feldspathic porcelain veneers 8a8b9Figs 8a and 8b Double-cord impression technique.Fig 9 Final impression. JURADO ET ALQDT 2020202were fabricated (Noritake Super Porcelain EX-3, Kuraray Dental) and the full-coverage crown was made of press-able feldspathic (Ex-3 Press, Kuraray Noritake (Figs 10a to 10e). Line angles were carefully deﬁned during the ﬁn-ishing of the ceramic veneers (Figs 11a and 11b).10a 10b10c 10d10e11a 11bFigs 10a to 10e (a) Master cast and alveolar dies for (b to e) fabrication of feldspathic veneers.Figs 11a and 11b (a) Deﬁning line angles and ﬁnishing of (b) ﬁnal feldspathic veneers. Optimal Tooth Preparation with Different Tooth Reduction Guides: Case Presentation QDT 2020203Bonding and PolishingA dry try-in of the ﬁnal restorations was performed to eval-uate the ﬁt and contours, and once the patient approved, the bonding procedure continued. A rubber dam (Dental Dam, Nic Tone) was placed from second premolar to sec-ond premolar and held with clamps (Clamp #00, Hu-Friedy) to achieve proper isolation. A clamp was also placed along the gingival margin of every tooth to be treated (Clamp B4, Brinker Hygenic), followed by sandblasting of the teeth with water and 29-micron aluminum oxide particles (Aqua-Care Aluminum Oxide Air Abrasion Powder, Velopex).Surface treatment of teeth with veneers was carried out with total etch of the enamel using 37% phosphoric acid (Total Etch, Ivoclar Vivadent) for 15 seconds and gentle air drying, followed by primer application and gentle removal of excess with air. Fourth-generation adhesive was applied (Syntac, Ivoclar Vivadent), with gentle removal of excess by air. The ceramic restorations were etched with 37% phos-phoric acid gel (Total Etch, Ivoclar Vivadent) for 15 sec-onds with gentle air-drying for 5 seconds, and then the light-shade bonding material was applied (Monobond Plus, Ivoclar Vivadent). Next, Variolink Esthetic LC (Ivoclar Viva-dent) was applied to the veneers, and the restorations were seated in place. Excess was removed followed by light curing (VALO cordless 6 oz, Ultradent) on the facial surface for 20 seconds, ﬂoss was used to clean the inter-proximal surfaces, followed by another light cure time of 20 seconds on each surface (palatal, mesial, and distal) of the veneer restorations. The single full-coverage crown was cemented with a dual-cure resin cement (Panavia V5, Kuraray Noritake) (Figs 12a to 12e).Excess of adhesive and cement material was removed. The occlusion was checked and adjusted, and restorations were polished with polishing points (Dialite Feather Lite, Brasseler) and polishing paste (Dialite Intra-Oral Polishing Paste, Brasseler).12a 12b 12cFig 12a Rubber dam isolation prior to bonding of ceramic veneers.Fig 12b Placement of Teﬂon tape on adjacent tooth.Fig 12c Bonding of ﬁnal ceramic veneers for central incisors.Fig 12d Placement of clamps on lateral incisors prior to bonding ceramic veneers.Fig 12e All-ceramic restorations bonded under rubber dam isolation.12d 12e JURADO ET ALQDT 2020204Final ResultTo protect the restorations, the patient was provided an oc-clusal guard to wear at night. She was pleased with the overall appearance of the restorations (Figs 13a to 13d). The 1-year follow-up evaluation displayed a good condi-tion of the soft tissue and ceramic restorations (Fig 14).DISCUSSIONThe advancements in adhesive dentistry have enabled a more conservative approach to esthetic dental procedures. Patients seek esthetic treatments to improve their healthy appearance, dentofacial harmony, and physical condition—in dentistry as well as medicine. Esthetic-driven patients can easily recognize any small abnormality or discrepancy in the anterior teeth. Figs 13a to 13d Patient’s ﬁnal restorations and smile.Fig 14 One-year follow-up.13a13b13c13d 14 Optimal Tooth Preparation with Different Tooth Reduction Guides: Case Presentation QDT 2020205Adequate reduction of tooth structure for veneer prepa-rations without the aid of a tooth reduction guide is chal-lenging. Overpreparation of teeth is a common mistake when guides are not used; this may lead to dentin exposure and decreased bonding properties. On the contrary, underprepar-ation of teeth will promote overcontoured restorations. The use of reduction guides is always indicated when prepar-ing teeth for porcelain veneers. The clinician needs to be-come familiar with the different types of guides in order to use those most adequate for a particular case. Putty guides are the most commonly used to evaluate thick ness and inci-sal reduction; however, they do not give a 360- degree view as does the clear matrix guide. Clear matrices can be perforat-ed in order to evaluate tooth reduction of a speciﬁc area. Despite the advantages of using these two types of matri-ces, both enable reduction of only a speciﬁc amount of tooth structure; therefore, in cases of protruded teeth re-quiring more reduction, a cast metal reduction guide or self-cured acrylic guide can provide the opportunity to se-lectively remove tooth areas that are protruded.Controlled tooth preparation can provide the ideal space for ﬁnal restorations fabricated conventionally by the den-tal technician or manufactured by milling. Moreover, con-servative tooth preparation can save tooth structure that will be needed for future full-coverage crowns when the restorations need to be replaced. Since none of the cur-rent dental prostheses can be guaranteed to last forever, the clinician should always consider taking a conservative approach by controlling tooth reduction.CONCLUSIONIdeal and conservative tooth preparations provide optimal space for adequate contour and thickness of the ﬁnal indi-rect restorations. The use of different tooth reduction guides for the same tooth preparation will help the clinician tre-mendously to avoid over- or under-reduction of teeth for the fabrication of successful restorations.ACKNOWLEDGMENTSThe authors declare that there is no conﬂict of interest regarding the publication of this paper.REFERENCES1. Rosentiel SF, Land MF, Fujimoto J. Contemporary Fixed Prosthodon-tics, ed 4. St Louis: Elsevier, 2006:209–257.2. Chen Y, Raigrodski A. A conservative approach for treating young adult patients with porcelain laminate veneers. J Esthet Restor Dent 2008;20:223–238.3. Holm C, Tidehag P, Tillberg A, Molin M. Longevity and quality of FDPs: A retrospective study of restorations 30, 20 and 10 years after inser-tion. Int J Prosthodont 2003;16:283–289.4. Libby G, Arcuri MR, LaVelle WE, Hebl L. Longevity of ﬁxed partial dentures. J Prosthet Dent 1997;78:127–131.5. Edelhoff D, Sorensen J. Tooth structure removal associated with various preparation designs for anterior teeth. J Prosthet Dent 2002; 87:503–509.6. Ozturk E, Bolay S, Hickel R, IIie N. Shear bond strength of porcelain laminate veneers to enamel, dentine and enamel-dentine complex bonded with different adhesive luting systems. J Dent 2013;41:97–105.7. Pincus CR. Building mouth personality. J South Calif Dent Assoc 1938;14:125–129.8. Aristidis G, Dimitra B. Five-year clinical performance of porcelain laminate veneers. Quintessence Int 2002;33:185–189.9. Friedman M. A 15-year review of porcelain failure: A clinician’s obser-vations. Compend Contin Educ Dent 1998;19:625–628, 630, 632 passim.10. Ferrari M, Patroni S, Balleri P. Measurement of enamel thickness in relation to reduction for etched laminate veneers. Int J Periodontics Restorative Dent 1992;12:407–413.11. Tjan A, Dunn J, Sanderson I. Microleakage patterns of porcelain and castable ceramic laminate veneers. J Prosthet Dent 1989;61:276–282.12. Christensen G. Veneering of teeth. State of the art. Dent Clin North Am 1985;29:372–391.13. Livaditis G. Indirectly formed matrix for multiple composite core res-torations: Two clinical treatments illustrating an expanded technique. J Prosthet Dent 2002;88:245–251.14. Magne P, Douglas W. Additive contour of porcelain veneers: A key element in enamel preservation, adhesion and esthetics for aging dentition. J Adhes Dent 1999;1:181–192.15. Fareed K, Solaihim A. Making a ﬁxed restoration contour guide. J Prosthet Dent 1989;61:112–114.16. Moskowitz M, Loft G, Reynolds J. Using irreversible hydrocolloid to evaluate preparations and fabricate temporary immediate provisional restorations. J. Prosthet Dent 1984;51:330–333.17. Gardner L, Rahn A, Parr G. Using a tooth-reduction guide for modify-ing natural teeth. J Prosthet Dent 1990;63:637–639.18. Bluche l, Bluche P, Morgano S. Vacuum-formed matrix as a guide for the fabrication of multiple direct patterns for cast post and cores. J Prosthet Dent 1997;77:326–327.19. Tan H. A preparation guide for modifying the mandibular teeth before making a maxillary single complete denture. J Prosthet Dent 1997; 77:321–322.20. Aminian A, Brunton P. A comparison of the depths produced using three different tooth preparation techniques. J Prosthet Dent 2003; 89:19–22.21. Cho S, Nagy W. Labial reduction guide for laminate veneer prepara-tion. J Prosthet Dent 2015;114:490–492. QDT 2020206M ASTERPIECE Clinical Approach to Fulﬁll Esthetic Requirements: The Challenge of Nature’s BeautyFulﬁlling esthetic requirements is essential for ante-rior restorative treatment. It is necessary to study the fascinating natural beauty of the dentition and its composition in order to raise esthetic results to the next level, with the knowledge that some limitations or unfavor-able conditions usually exist in reality. Improvement of the prosthetic condition plays an important role in the ability to carry out prosthetic treatment effectively. A comprehensive treatment approach with collaboration between the clinic and laboratory is instrumental to the result.Part of the reproduction concept and the author’s chal-lenge to recreate nature’s beauty are presented here, along with clinical cases illustrating the approach for fulﬁll-ing the esthetic requirements.Clinical Approach to Fulﬁll Esthetic Requirements: The Challenge of Nature’s BeautyYuji Tsuzuki, RDTRay Dental LaborElitz Yamashina Building 3F18-8 Takehanatakenokeidocho Yamashina-kuKyoto City, KyotoJapanEmail: [email protected] 2020 TSUZUKIQDT 2020208CASE 1EXCELLENT OPTICAL PROPERTIES— PLAY OF COLOR — Clinical Approach to Fulﬁll Esthetic Requirements: The Challenge of Nature’s BeautyQDT 2020 209In this case, the central incisors were restored with all- ceramic crowns. The edge-to-edge occlusal relationship and shallow anterior coupling were taken into consideration in the framework design. The IPS e.max Press Impulse Opal 2 ingot (Ivoclar Vivadent) was chosen and the facial cutback technique was employed considering reproducibility of the color.The advantage of the facial cutback technique is its high color reproducibility, maintaining the strength of IPS e.max Press. It is possible to choose the ingot according to the translucency of the incisal edge utilizing opaque porcelain. Impulse Opal ingot has superior optical properties in addition to high translucency, and the opal effect of natural teeth can be readily reproduced. Thus, utilizing the particular characteristic of the material precisely expands the range of clinical applications.Dentist: Dr Hiroyuki Takino (Takino Dental Clinic) TSUZUKIQDT 2020210The maxillary right central incisor was restored with an implant in this case. Hard and soft tissue graft procedures were carried out to restore the V-shaped divulsion on the labial aspect. The prosthetic condition was dramatically improved by a proper surgical procedure. Maintenance and stability of the soft tissue depends on the implant superstructure. The abutment is a hybrid design with titanium base and bonded zirconia, and the crown is fabricated with the IPS e.max Press system.Dentist: Dr Hiroyuki TakinoEXACT REPRODUCTION OF NATURAL DENTITIONCASE 2