Renewing the Smile Zone: Changing Our Patients’ Lives

EXAMINATION, DIAGNOSIS, AND TREATMENT PLAN
Steve is small business owner who wished to have his smile improved. From a full-face view (Figure 1), you can see that he had what I call an “acquired” smile. He tended to hold his lower lip up to disclose less of his teeth when he smiled (Figure 2). The retracted view in Figure 3 shows that his mandibular right lateral incisor and both central incisors had been previously restored with porcelain-fused-to-metal (PFM) crowns. His maxillary right canine and lateral incisor had also received PFM crowns. The patient had diastemas between both lateral incisors and the adjacent canine teeth that he wished to have closed. The maxillary central incisors were not symmetrical. The left central had a higher zenith than the right one. They were not mirror images as we would have preferred. The retracted left lateral view (Figure 4) shows that the maxillary left lateral incisor was narrower than the “golden proportion” of 1 to 1.6 as compared to the adjacent central incisor. Figure 5 shows an occlusal view of the maxillary arch showing the teeth that were in what we consider to be the “smile zone.” The mandibular occlusal view can be seen in Figure 6.

Figure 1. Preoperative full-face view.	Figure 2. The patient’s acquired smile before treatment.
Figure 3. Retracted preoperative facial view.	Figure 4. Left lateral retracted preoperative view.

The patient’s periodontal health was excellent, with no periodontal pockets over 3.0 mm in depth. There was no bleeding upon probing and his mouth was devoid of calculus and plaque. The crown-to-root ratio was good with no detectable bone loss. Steve was maintaining his present restorations well. I consider this type of patient a good can­didate for elective dentistry. Had he exhibited dental or periodontal disease, I would have advised him to focus on reversal of disease before advancing to elective procedures. However, Steve desired a replacement of his previous crowns and addition of ceramic veneers to change his smile to an appearance that he felt was more aesthetic.
His occlusion was class I with a slightly deep overbite. I did not plan to change his occlusal scheme, which was functioning well. His vertical dimension would remain constant. He occluded in centric relation and had no interferences in centric or excursive movements. Anterior guidance with posterior disclusion would be maintained in the final restorations. Our treatment plan was to treat the maxillary 10 teeth from second premolar to second premolar for aesthetic improvement within functional limits.
At the preoperative appointment, a facebow record was taken (Denar Slidematic [Whip Mix]) and a CR registration was made with a hard setting polyvinylsiloxane (PVS) bite registration material (O-Bite [DMG America]). Upper and lower impressions were taken with a PVS alginate substitute material (Status Blue [DMG America]). The dental laboratory technicians would use these records to pour-up study models and mount them on a semi-adjustable articulator (Denar [Whip Mix]). A full wax-up of the desired finished result would be accomplished on the mounted models and a polyvinyl putty matrix would be made from this wax-up for fabrication of provisional restorations.

PREPARATIONS

Figure 5. Preoperative maxillary occlusal view.	Figure 6. Preoperative mandibular occlusal view.
Figure 7. Retracted facial view of prepared teeth.	Figure 8. Left lateral retracted view of prepared teeth.

At the preparation appointment, the man­dibular arch was anesthetized first using bilateral mandibular blocks. The left lateral incisor, both canines, and the first and second premolars were to be prepared for veneers. Facial depth cuts were made at 0.5 mm with the LVS1 diamond bur (Brasseler USA). The depth cuts were joined using the LVS3 bur (Brasseler USA) leaving chamfer margins at the height of the tissue. The preparation was taken into the proximal areas to form el­bow preparations that stopped at the proximal contact areas. Incisal edges were then reduced by 1 mm and butt margins were formed over the incisal edges of the canines and lateral incisor. The KS1 diamond bur (Brasseler USA) was used to form “window” preparations over the cusp tips of the 4 premolars so that “new” cusp tips could be formed in porcelain.
The KS1 diamond bur was used to break through the porcelain surfaces of the 3 crowns and a metal-cutting carbide (H-54012 [Brasseler USA]) was used to cut slots through the metal foundations. A crown spreader instrument (B-13416 [Brasseler USA]) was used to torque the crowns off of the prepared teeth. The left central incisor had been endo­dontically treated and would need a post. The post space was prepared and a fiber post (LuxaPost [DMG America]) was bonded to place with a composite resin cement (Multilink Automix [Ivoclar Vivadent]) that utilizes a self-etching primer. The luting composite itself was used as the core material. The 3 crown preparations were refined and finished with chamfer margins at the height of the tissue. A PVS bite registration (Regisil Rigid [DENTSPLY Caulk]) was taken at this point so the dental laboratory technician could “jump” the prepared model to the mounted preoperative model on the articulator.
The maxillary arch was then anesthetized using local infiltration from second premolar to second premolar. Three hundred sixty degree laminate preparations were accomplished on both central incisors, the left lateral incisor, and the canine. A football-shaped diamond (5379 023 [Brasseler USA]) was used to reduce the lingual aspect of these teeth to allow for a porcelain thickness of at least 0.5 mm.

Figure 9. Maxillary occlusal view of prepared teeth.	Figure 10. Mandibular occlusal view of prepared teeth.

My objective was to establish porcelain-to-porcelain contact in centric and excursive movements for the 6 anterior teeth. Depth cuts were accomplished with the KS1 diamond bur. These were then joined with the KS3 forming chamfer margins at the height of the tissue. Veneer preparations were accomplished for the 4 premolar teeth using the same technique as for the mandibular teeth except that no window preparations were used. The preparations were stopped at the cusp tips without extending over the occlusal surfaces. Horizontal seating grooves were placed in the facial surfaces of the premolar teeth. The 2 PFM crowns were removed with the same technique as before. Chamfer margins were redefined at the tissue level.
A diode laser was then used to raise the tissue levels of the right lateral and central incisors. Finally, all margins were refined using a chamfer-ended fine grit finishing diamond bur. All preparations were smoothed and polished using an Enhance (DENTSPLY Caulk) point. The final preparations can be seen from the facial aspect in Figure 7. A left lateral view of the finished pre­p­arations is shown in Figure 8. Figure 9 shows the incisal view of the maxillary preparations, and Figure 10 shows the mandibular preparations from the incisal aspect.

IMPRESSIONS
No cord was used for hemostasis. Instead, an aluminum chloride astringent in a putty base (Expasyl [Kerr]) was used. Full-arch final impressions were taken using a PVS impression material (Flexitime [Heraeus Kulzer]). In addition, another bite registration was taken with a hard setting PVS bite registration material (Regisil Rigid [DENTSPLY Caulk]) for mounting the maxillary model of the prepared teeth to the mounted model of the mandibular prepared teeth on the semi-adjustable articulator.

PROVISIONALIZATION
A bisacrylic provisional material (Luxatemp [DMG America]) was injected into the polyvinyl putty matrix fabricated earlier by the dental laboratory technician using the diagnostic wax-up of the proposed final restorations. The putty matrix was placed over the prepared teeth and the provisional material was allowed to set fully. When the matrix was removed, the bisacrylic material remained on the prepared teeth and the excess at the margins was removed with a small carbide finishing bur (ET3 [Brassler USA]) in a high-speed handpiece. Then, the margins were smoothed and polished using an Enhance (DENTSPLY Caulk) cup in a slow-speed handpiece.

RESTORATION FABRICATION

Figure 11. Maxillary restorations on a mirrored surface.	Figure 12. Mandibular restorations on a mirrored surface.

At the dental laboratory (The Center for Ceramics at the Nash Insitute), the impressions were poured and the models of the prepared teeth were mounted on the articulator. Twenty all-ceramic (Venus [Heraeus Kulzer]) restorations were fabricated. This system allows for the fabrication of pressed cores exhibiting excellent fit and high strength. Layering porcelain was then stacked and fired over the cores to create the desired aesthetic effects. The final restorations for the maxillary arch are shown on a mirrored surface in Figure 11. The mandibular restorations can be seen in Figure 12.

Try-In and Delivery
At the delivery appointment, the patient was anesthetized and the provisional restorations were removed. The restorations were tried-in using water as a try-in medium. Since the shading was good using water, it was decided to use a neutral or untinted luting agent to bond the restorations into place. Should a tinted try-in paste be used, we would have made sure the try-in paste was thoroughly removed to keep the ceramic surfaces from being contaminated. During the try-in, the restorations were checked for fit, contacts, and aesthetics. Steve was also given the chance to check and approve the restorations. Then, they were removed and placed in an organizer so that the assistant could prepare them for the bonding process.
The internal surfaces of the restorations were thoroughly cleaned (acetone), rinsed, and dried. Silane (Silane Primer [Kerr]) was then applied with a brush to the (cleaned and laboratory-etched surfaces) of the restorations and dried with a blast of air from an air/water syringe.
A dual-cured composite resin luting agent was chosen (Nexus 2 [Kerr]) and used with OptiBond Solo (Kerr), the corresponding bonding agent used with a total-etch technique. The restorations ranged from 0.5 mm thick for some of the veneers, to 1.0 mm thick (or more) for the crowns. Using a dual-cured material insured that all of the luting agent would be cured, even if light was unable to reach it. The dual-cure technique is also one that allows for an efficient clean up of any excess cement at the gel stage.
The 6 maxillary anterior teeth from canine to canine were etched with 37% phosphoric acid gel for 10 seconds and rinsed. A wetting and desensitizing agent (Gluma [Heraeus Kulzer]) was liberally applied with a brush. A high-speed suction tip was placed near the 6 teeth to remove excess Gluma, and the teeth were left slightly moist for the wet bonding process. The dual-cured Opti­Bond Solo was mixed and liberally applied to the 6 slightly moist teeth using a brush. Air from an air/water syringe was then used to remove the ethanol carrier in the bonding agent and any remaining water on the teeth. A glossy surface remained showing the proper resin layer which was left on the tooth structure. Nexus 2 catalyst and base were mixed and placed into each restoration. Each restoration was set to place and a veneer stabilizer instrument (Brasseler USA) was used to hold each veneer in place until the gel stage was reached. (This is approximately 3 minutes after the start of the mix.) As the luting composite began to gel, it was gently teased away from the margins using the scaler on the other end of the stabilizer instrument. Floss was worked in between each restoration and pulled to the fa­cial to remove excess luting composite there. The distal aspects of the canines were completely cleared to allow for placement of the adjacent veneers. A visible light-curing unit was used to finish the polymerization for the first 6 restorations by curing for 20 seconds on the facial and 20 seconds on the lingual. The same process was used to bond the veneers on the 2 right maxillary premolars, and then, the 2 maxillary left premolars.
The mandibular crowns and the veneer on the left lateral incisor were placed next. The same technique outlined above was used here. The porcelain veneers for the mandibular right canines and premolars were placed next, followed by the left canine and premolar veneers.
Finally, the occlusion was checked with articulation paper. A slightly heavy contact was found on the right lateral incisor. An adjustment was made by using a 30-µm grit-finishing diamond bur (D0S1F 023 [Brasseler USA]). A 15-µm grit diamond bur followed by a 30-fluted carbide-finishing bur (D0S1EF 023 [Brasseler USA]) was used to smooth the adjusted area. Porcelain polishing points (CeramiPro Dialite W16DG, W16DM, W16D [Brasseler USA]) using 3 successive grits were used to bring the adjusted surface to a high gloss and a smooth surface.

FINAL RESULTS

Figure 13. Retracted facial view of finished case.	Figure 14. Left lateral retracted view of finished case.
Figure 15. Postoperative maxillary occlusal view.	Figure 16. Postoperative mandibular occlusal view.
Figure 17. Postoperative anterior view.	Figure 18. Steve’s new smile.

The final results can be seen in Figures 13 to 18. Steve’s new smile exhibits well-aligned teeth that are lighter in color. His new smile is wider, his lower lip drops down further, and he does not hesitate to show his teeth when he smiles. In fact, he commented at his postoperative appointment that he was very happy and that the dental makeover accomplished his goal for feeling more self-confident.

Dr. Nash is president and cofounder of the Nash Institute for Dental Learning in Charlotte, NC. He owns and operates Cosmetic Dentistry of the Carolinas located in Huntersville, NC, where he and his associates provide general, aesthetic, and cosmetic dental care. Dr. Nash is an accredited Fellow in the American Academy of Cosmetic Dentistry and a Diplomat of the American Board of Aesthetic Dentistry. An international presenter on dental aesthetics and oral rehabilitation, he is also a consultant to numerous dental products manufacturers. He can be reached at (704) 364-5272 or ross@nashinstitute.com, or visit his Web site at nashinstitute.com.

Disclosure: Dr. Nash reports no conflicts of interest.