Winter Wonderland: Creating a Socially Celebrated Smile

The recent advent of social distancing and the resulting increase in health safety awareness have also successfully inspired new methods of digital communication in dentistry, including esthetic consultations via online virtual platforms. Patients can openly discuss their anxieties and esthetic goals with their dental providers and be educated about the next steps to take in realizing their perfect smiles. Consumers with compromised self-images due to factors such as congenital issues, tooth discoloration, disproportionate tooth shapes, and chipping or significant wear may not be satisfied with orthodontic alignment and chemical whitening solutions alone. For dentists, crossing the virtual bridge and providing the most conservative options to complement the desired outcome of patients—while fitting within their available budgets—can be as challenging as performing the treatment itself.

Dentists who confidently offer thin, long-lasting veneer restorative options that are minimally invasive can discover an increase in patients who are motivated to expand the potential of their smiles and willing to accept treatment. When strategically analyzed by both the clinic and the laboratory, it has been found repeatedly that little to no preparation is required in order to achieve the same competitive results traditionally found in cases where more aggressive preparations have become part of the standard course of treatment.

Since their introduction in the early 1900s, porcelain veneers have become an established and proven treatment option with very high, long-term success rates.¹ Retrospective studies have revealed that porcelain veneers have the highest survival rate (eg, 99%) when the preparation is confined to enamel.^1-3 Practitioners can take advantage of the high success rates of this treatment modality and increase patient motivation to accept treatment by offering minimal-thickness porcelain restorative options.

Although the esthetic properties of a feldspathic approach to veneers may be favored by the industry within a limited restorative environment, many laboratories wrestle with the technical challenges associated with space constraints, cost efficiency, and incorporating the necessary analog materials into their modern digital workflows. Leveraging the material science of pressed lithium disilicate, the following case ventured to maximize the results of both beauty and strength that are hidden within the layers of socially celebrated smiles.

Case Report

Winter, a healthy, 24-year-old female patient, presented to the practice for options to improve the quality of her smile. Previously, she had used an online portal (Oryx Dental Software, Oryx) to fill out a new patient questionnaire, which was used to gain comprehension of her oral health and medical risks.⁴ The patient's first in-office appointment included the acquisition of a series of detailed 2D images and videos to assist the dentist in understanding her concerns as well as to evaluate the condition of her entire dentition. Although the patient was never seated in a dental chair while visiting for the consultation, clinical records were assembled through detailed inquiry, intraoral scanning, and digital SLR photography, which provided the dentist and technician with adequate information to discuss treatment considerations (Figure 1 through Figure 3). An additional series of photographic records, including practical images that captured authentic facial expressions, was useful to go beyond the static positions of clinical protocol and accentuate her personality.

The patient's ultimate goal was to have bigger, longer, and whiter teeth as well as a fuller smile. To accomplish this, she was presented with conservative treatment options that included whitening and selective bonding to increase the incisal edge position, no-preparation direct veneers, and no-preparation indirect veneers. It was decided that the patient would receive the most benefit from having her maxillary anterior teeth treated with no-preparation porcelain veneers; however, her budget did not allow for all 10 of her visible maxillary teeth to be treated. The option of fabricating porcelain veneers for her maxillary incisors and canines and placing direct veneers for her four maxillary premolars was presented as a lower-cost alternative. The patient exhibited moderate incisal edge wear of the anterior dentition, which was from attrition, but significantly less enamel loss on the occlusal surfaces of the posterior anatomy.

Treatment Planning

The initial records were shared with the restorative technician and evaluated to determine appropriate tooth lengths and shapes to complement the fundamental facial proportions that were unique to the patient. The digital design would be used to create a mock-up for provisionalization as well as a matrix for the chairside fabrication of the premolar veneers. In order to decrease the selective wear of the patient's anterior teeth, she would be deprogrammed and equilibrated to achieve a stable bite position with the temporomandibular joints in their most orthopedically correct positions.^5,6 When treatment planning restorations that restore anterior teeth to their original lengths, favorable results have been achieved by equilibrating patients who present with anterior wear without the presence of posterior wear. A lithium disilicate material (IPS e.max^® Press, Ivoclar Vivadent) was selected for the fabrication of the final anterior no-preparation veneers because of its combination of strength and beauty and the ceramist's ability to successfully refine it for the no-preparation technique.

After the patient was deprogrammed and equilibrated, she was scanned with an intraoral scanner (3Shape TRIOS^®, 3Shape), and photographs were taken with an earless facebow (EZ Bow System, Advanced Dental Designs) to assist the technician in mounting the case (Figure 4).⁷ The facebow's lasers and levels are used to record the patient's occlusal plane relative to the true horizontal plane. Using these results, the dentist and technician collaborate to determine what changes need to be made to the angle of the smile related to the horizontal plane and the patient's facial esthetics.

Once articulated, the diagnostic proposal was digitally simulated by marrying the .STL files with the 2D clinical photography. Accurately positioned 2D records were essential to the restorative communication and key to a predictable digital workflow. By merging multiple files, the virtual design software was able to easily sync the topographical landmarks of the teeth and face (Figure 5).⁸ Diagnostic tooth positions were proposed by integrating the facebow records using digital dentofacial analysis software (Smile Creator, exocad). The design was created to be additive and represent thicknesses that the technician would be able to replicate in lithium disilicate for the final ceramics.⁹ After the dentist and technician reviewed the proposed designs virtually to facilitate conversation, the final design was determined, and diagnostic models were fabricated. The 2D diagnostic proposal was also used as a visual communication tool with the patient (Figure 6). Prior to the first clinical appointment, the laboratory delivered 3D printed models along with a putty matrix for the direct veneer fabrication for the premolars and a putty matrix for anterior provisionalization.

Prototype Provisional Restorations

The patient returned to the office for an esthetic evaluation of the digital design, direct veneering of her four maxillary premolars, and provisionalization of her six maxillary anterior teeth. First, the teeth were cleaned with a pumice paste (Pumice Preppies^™, Whip Mix) that was mixed with a 2% chlorhexidine gluconate solution (Consepsis^™, Ultradent Products, Inc.). An intraoral mock-up was then fabricated by filling the laboratory matrix with bisacryl material (Luxatemp [shade BL], DMG America). After the excess material was removed, the mock-up was refined. The patient's esthetics were evaluated with her in a standing position and documented in the studio with photographs and a video recording. This video was shared with the patient, and she was also provided with a mirror to evaluate the prototype of the final restorations.

With patient approval of the treatment proposal, the direct veneers were fabricated using the laboratory-supplied putty matrix. Once the direct veneers were finished, a master impression was made of the maxillary arch (Virtual^®, Ivoclar Vivadent). Teeth Nos. 6 through 11 were isolated, impressions were made, and a bite was recorded. To help the patient achieve her ideal tooth color, detailed shade tab (Natural Die Material Shade Guide, Ivoclar Vivadent) photographs of the existing dentition were taken and shared with the technician to assist in ingot selection for the final veneers (Figure 7). Because the patient's teeth were a darker shade, her thinner restorations would require more opacity to achieve the brighter results she desired. Therefore, a shade (IPS e.max^® Press [Low-Translucency, Bleach 1], Ivoclar Vivadent) was chosen for her final veneers that would deliver the brightest esthetic while providing the strongest opacity in transitionally thin areas.

The prototype provisional restorations were fabricated by filling the laboratory matrix with bisacryl material (Luxatemp [shade BL], DMG America) using the shrink wrap technique. Once placed, they were scanned with the intraoral scanner and photographed in the studio to record the esthetics for the ceramist (Figure 8). A new facebow record was taken and photographed, and a goal shade of Vita OM1 was captured next to the provisional restorations. The ceramist was scheduled to be present during the provisional evaluation.

At the provisional evaluation, in addition to photographic confirmation, an incisal putty index was created to verify any length or embrasure modifications made chairside, which may differ slightly from the original diagnostic model, and scans of the adjusted provisional restorations were also 3D printed to be used as reference models during contouring of the final layered porcelain restorations. This personalized collaboration helps to boost patient confidence and motivates engagement during the process because open discussion of minute preferences promotes equilateral trust in the results to come. It is energizing for patients to see both the dentist and technician passionately combine their interdisciplinary skills and techniques to customize ceramics for them. During this appointment, patients commonly express their desire for subtle enhancements that they hope to see reflected in the final porcelain esthetic, and bigger and whiter teeth are a common request.

It is highly valuable to carefully listen to the patient's input during the provisional evaluation. Although natural colors and respected rules of proportion¹⁰ may be clinically acceptable to the cosmetic team, certain patient preferences for enhanced beauty may call for "larger than life" modifications to balance distinctive features inherent in the patient's composition.

Detailed notes and exacting measurements help to eliminate misconceptions and allow the ceramist to deliver his or her finest precision for the case. To avoid confusing the patient with technical industry jargon or proprietary product terminology, the specific shade, fluorescence, value, and opacity level of the lithium disilicate were determined privately by the ceramist and dentist through photography and observation.

In the Laboratory

Digital CAD/CAM software (DentalCAD, exocad) was utilized to design the six individual maxillary anterior veneers in reference to the updated scan of the adjusted provisional restorations. The designs were converted into .STL files, and the individual units were milled from wax. These units can also be 3D printed using a combustible resin material for pressing. After the wax margins were hand finished to a minimum thickness of 1 mm and sprues were attached, the lithium disilicate ingot was uniformly pressed into the pattern. This process allows the pressing material to evenly flow into the extents of the wax design. Successful pressing requires every stage of the process to be regarded as a work of art (Figure 9).

Once the pressing cycle was completed, the six anterior units were divested and separated from their sprues using a fiberglass reinforced separating disc (Dynex Brilliant [0.3 mm], Renfert) at slow speed. The units were then seated to individually trimmed dies and refined at the margins using soft and medium abrasive wheels at extra slow speed with a continuous application of water. It is important to note that excessive RPM, external forces, heat, and friction can result in microfracturing and quickly disqualify lithium disilicate material for use in areas needed to mimic feldspathic porcelain. After the margins were sufficiently thinned, the interproximal contacts were adjusted, and the units were seated on a solid cast (Figure 10). Great care was taken as the lithium disilicate material was finessed to thinner extremes.

Digital calipers and an incisal putty index were used to verify the updated tooth lengths and shapes before beginning to add incisal details to the porcelain. A 3D printed model of the recent scan provided an ideal side-by-side reference for reshaping the embrasures and precontouring the fuller areas of the lithium disilicate to exactly reproduce the patient's approved provisional changes (Figure 11). Using a medium course, knife-edged stone wheel at slow speed, the incisal edges were vertically reduced by a minimum of 0.3 mm and facially beveled by a minimum of 0.5 mm to account for layering the translucency of the enamel in porcelain (Figure 12). The adjusted surfaces were then steamed to remove any particulate matter and other contaminant residue, and a thin foundational wash of fluorescing paste was applied to the surface of each unit. Next, size 000, 001, and 003 stain brushes were used to imitate the effects of intrinsic mamelon structure. This "wash layer" was then fired at a lower temperature (eg, 700°C) to set the foundational effects and serve as a bonder layer over the lithium disilicate veneers for the higher fusing porcelains (Figure 13).

Veneering porcelain (IPS e.max^® Impulse [OE1], Ivoclar Vivadent) and stain and glaze powders (IPS Ivocolor Essence, Ivoclar Vivadent) were combined in a 2:1 ratio and applied to the incisal bevel to create visual depth at the mesial and distal corners and to simulate the separate development of mamelons. Because different mixing ratios can weaken or intensify the outcome of the incisal effects, this process is subject to patient preferences. These first opal effects of the incisal framework were then fired at a higher temperature (eg, 750°C) (Figure 14).

After firing, the incisal putty index was used to verify mamelon details and guide the ceramist during the final layering of veneering porcelains (Figure 15). For the final layer, veneering porcelains (IPS e.max^® Impulse [OE1], Ivoclar Vivadent) (IPS e.max^® Impulse Power Incisal [1], Ivoclar Vivadent) were combined in a 4:1 ratio, applied at full contour (Figure 16), and fired at 750°C to maintain the integral properties of the porcelain (Figure 17).

Following bisque firing of the full-contour porcelain, a visual map was drawn on the restorations to guide the refinement of the facial anatomy and the final esthetic contouring (Figure 18). A fine tapered diamond bur was used to transition the layered porcelain into the precontoured anatomy of the lithium disilicate, and then a medium soft abrasive wheel was used to smooth the axial line angles and prepolish the restorations before applying the final glaze (Figure 19). The use of reverse imaging and desktop mirrors was crucial in visualizing the line angles and critical zones of symmetry to finalize the esthetics (Figure 20). During final refinement, the reflective dynamic translates better from model to mouth if the lighting influence over the technician's workspace is set up to approximate the flash of the clinical camera. Stronger or softer light reflections can help bring porcelain to life and are dependent on the conditions of the environment. Once the reflections were in harmony, the veneer surfaces were steamed free of any residual polish, and their intaglio surfaces were etched and prepared for clinical adhesion.

Final Veneer Delivery

At the delivery appointment, the provisional restorations were removed, and the prepared teeth were cleaned. The ceramic veneers were tried in one at a time for fit and then two at a time to check the contacts. Noting some areas of difficult fabrication over the existing dentition, the dentist polished any appropriate line angles and edges to facilitate passive seating. The veneers were then tried in with a neutral try-in paste (Variolink^® Esthetic Try-In, Ivoclar Vivadent) to hold them in place to evaluate the final color. The shade of ingot selected, even at the restoration's thinnest points, opaqued much of the natural tooth color and created a very white shade to achieve the patient's color goal. She was photographed in the studio, and the images were reviewed with her on a large monitor. Before and after images were put up on the screen to fully convey the dramatic change that was achieved. At this time, any final patient concerns could be addressed prior to bonding the restorations.

After isolation was achieved using a split, latex-free rubber dam (HYGENIC^® Flexi Dam^®, Coltene), a knitted retraction cord was placed (Ultrapak^™ [No. 000], Ultradent Products Inc.) (Figure 21). The teeth were then prepared by cleaning with a non-fluorinated prophy paste mixed with 2% chlorhexidine gluconate solution, performing particle abrasion, and employing a total etch technique. Once the teeth were prepared, a universal adhesive (Adhese^® Universal, Ivoclar Vivadent) was placed (Figure 22) and light cured to the manufacturer's specifications. The veneers were then bonded (Variolink Esthetic^® LC [neutral], Ivoclar Vivadent) into place using the tack and wave technique. To accomplish this, each veneer was held firmly with soft pads (OptraSculpt^®, Ivoclar Vivadent) while the dental assistant cured the dead center for one second with a 1-mm tack tip on an LED curing light (Bluephase^® PowerCure, Ivoclar Vivadent) (Figure 23). This permitted the excess cement to be easily lifted away from the margins of the veneers (Figure 24). Next, the contacts were separated with a restorative strip (ContacEZ Restorative Strip System, ContacEZ) followed by floss, and any remaining remnants of cement were cleaned up with a No. 12 scalpel blade. The retraction cord was removed, and a glycerin gel (Liquid Strip, Ivoclar Vivadent) was placed for the final curing. Prior to ending the appointment, the occlusion was refined, and the margins were finished with a diamond polishing needle and polishing points (Dialite^®, Brasseler USA) (Figure 25).

Conclusion

The patient returned 2 weeks later for her postoperative appointment, where the occlusion of the restorations was checked, and new images were taken of the final ceramic (Figure 26 through Figure 28). Ultimately, the patient's goals for a socially celebrated smile were achieved through placement of ultra-thin lithium disilicate no-preparation veneers. Oftentimes, teeth in these situations are aggressively prepared only to achieve similar or even less esthetic results; however, with proper treatment planning, excellent technique in the fabrication of thin pressed lithium disilicate restorations, and the ability to deliver them successfully during cementation, the option exists to provide veneers that are thin enough and bright enough to make patients happy with minimal or no removal of the natural enamel. The result is a makeover for the patient that fulfills his or her goals for a new smile with a conservative treatment modality (Figure 29 and Figure 30).

About the Authors

Jason Olitsky, DMD, AAACD
Private Practice
Ponte Vedra Beach, Florida

David Anderson
In-house Ceramist
Ponte Vedra Beach, Florida