October 2010, Volume 6, Issue 9
Published by AEGIS Communications
Improving the Past with the Economic Realities of Today
Acceptable compromises in treatment planning can result in satisfying esthetic and functional outcomes.
With economic times as uncertain as many have seen in their lifetimes, it is becoming increasingly challenging to assist patients with "want" dentistry. The obstacles can become magnified when balancing the ideal pathway with the realities of one's discretionary funds. As such, treatment recommendations can become an acceptable compromise while still ensuring an improved outcome. In this specific case, achieving a blended result between full-coverage and veneer restorations added to the esthetic demands of a satisfying outcome.
The patient, a vivacious 26-year-old woman who worked in the cosmetics industry, presented with an attractive smile marred by four unattractive veneers (Figure 1 and Figure 2). These restorations were approximately 10 years old and were characterized by stained margins and being opaque in appearance and bulbous in nature with no suggestion of color gradation. Teeth Nos. 7 and 8 had been previously endodontically treated. When viewed from the incisal, the existing individual veneers were not symmetrical, contributing to the bulbous contour (Figure 3). The appearance was further compromised when examining the gingival zenith of teeth Nos. 7 through 10, with a lack of symmetry at the margins noted.
After viewing the initial study models and photographs, it was evident that the gingival height of teeth Nos. 6 and 11 were not on the same plane, setting up further discrepancies among the four incisors. Moreover, a slight midline cant to the left was of concern to the patient. When considered as a sum, there were a number of issues to address and a decision had to be made to obtain a wish list vs achievable priorities. Because the canines displayed a pleasing contour, it was suspected that there was a mild cant, which resulted in the appearance of teeth Nos. 6 through 8 being shorter than teeth Nos. 9 through 11. To correct this appearance, gingival surgery may have unnecessarily exposed cementum and may not have achieved the desired result. The ideal pre-prosthetic treatment would suggest orthodontics to level the gingival contours among the four incisors framed by the canines. As the patient was looking for a more immediate result, time and additional finances were a strong consideration in the final treatment decision. To help visualize the outcome, a diagnostic wax-up was completed so that the patient could better understand the anticipated result (Figure 4).
From a technical perspective, it was decided that teeth Nos. 7 and 8 would be treated with full-coverage restorations and teeth Nos. 9 and 10 would be maintained as all-ceramic veneers. At this stage, it is critical that the clinician has confidence that the ceramicist can deliver a "mixed media" that, when bonded, presents as a single type of restoration. Understanding the procedure and recommendations for two crowns and two veneers, the patient requested to proceed with treatment.
Treatment was initiated with the removal and placement of the core restorations on teeth Nos. 7 and 8. Subsequently, these teeth were prepared for full-coverage restorations. Teeth Nos. 9 and 10 were then prepared for veneers. This preparation was accomplished by following the gingival contour past the sulcus with the finish lines ending at the mesial-lingual and distal-lingual line angles. This technique ensured a predictable fit at seating, an excellent emergence profile at the contact points, and restricting staining of the margins to the lingual where they could be easily accessed and cleaned. Care and attention was taken to ensure that the margins did not go further than 0.5 mm into the sulcus, to respect that the biological width was not violated and tissue tone was preserved (Figure 5). Once all of the preparations were complete, the margins were inspected for visibility and the body of the preparation was inspected from the incisal inward to ensure that there was sufficient reduction from the labial. Satisfied that the preparations were ideal, they were ready for the final impression procedure.
Before taking the final impression, the sulcus was not packed so as to avoid mechanical manipulation. Expasyl™ (Kerr Corporation, http://www.kerrdental.com) was placed in the sulcus to achieve hemostasis and retraction. The material was left on for 2 minutes then washed off with copious amounts of water and the teeth were then dried (Figure 6).
The impression was taken using Flexi- time® heavy and medium flow (Heraeus Kulzer, http://www.heraeus-dental-us.com) (Figure 7 and Figure 8). This material was selected because it is a polyvinyl siloxane with a new technology called Therma Sense. The material has a 2.5- minute set time with onset becoming more rapid once it is exposed to the oral tissues. This material also exhibits good flowability and an extremely low contact angle that allows for the precise capture of detail in moist environments. Dimensional stability is achieved through exceptional toughness of the material, which prevents tearing and distortion upon removal. As such, this material is ideal to provide the ceramist with an impression upon which to fabricate a working model. The impression, opposing arch, occlusal registration (Kois Dental Facial Analyzer) and laboratory script were packaged and sent to the ceramist.
As teeth Nos. 7 and 8 had to be temporized 360° and teeth Nos. 9 and 10 had to be temporized as veneers, temporary coverage was achieved in the following manner. Full-crown temporary coverage was fabricated for teeth Nos. 7 and 8. The occlusion was adjusted and the face of both temporaries were prepared for pseudo-veneer restorations. The full-coverage temporaries were then temporarily cemented. Spot-etch was applied to the center of teeth Nos. 9 and 10. The etch was washed off after 20 seconds and non-filled bond was applied to the entire surface of the tooth and temporary restorations (Figure 9). A non-filled bonding agent was used so that removal of the temporary restorations would be straightforward. Using a clear silicone matrix fabricated from the wax-up, the buccal surfaces were filled with a flowable resin positioned in the mouth and cured through the matrix (Figure 10 and Figure 11). Once the flowable resin was completely cured, the matrix was removed and a final cure was performed. Using esthetic trimming burs, the excess flash was removed and the occlusion was adjusted (Figure 12). The contour was fashioned and the surfaces were polished. By temporizing in this manner, with the temporary crowns acting as sleeves with the veneer overlay, there was consistency in the appearance of the temporaries (Figure 13). The patient was dismissed and appointed to insert the final restorations.
In order to establish parameters for the restorative treatment plan, the patient attended a consultation with the ceramist prior to commencement of her treatment to discuss her esthetic demands. Communication with the patient was essential to assist with the diagnostic treatment plan. Preoperative photographs were taken to facilitate the correct orientation for the blueprint to be established. This blueprint was used to set the restorative protocols for the complete treatment plan. The gingival asymmetry present between the two maxillary central incisors was considered a situation the patient could live with, especially as her gingival architecture did not visibly show under normal social circumstances. Based on the patient's wishes for increased length of tooth, enhanced facial symmetry, and greater visibility of her maxillary incisors, the diagnostic wax-up became an integral part of the planning process. With the assistance of the preoperative photographs for orientation of the preoperative models, and with the use of the Kois Dental Facial Analyzer, the duplicate models were cross-mounted on an articulator. In addition to the diagnostic wax-up, which represented the patient's esthetic demands and function, a silicone matrix for the provisionals and several diagnostic reduction stents to allow for correct tooth preparation and alignment were used to assist in case planning. Ensuring that the clinical preparation and marginal contours were idealized and in harmony with the proposed treatment plan would maximize the esthetics and promote good occlusion and function. Following these principles ensures patient satisfaction, which in turn promotes longevity for the provisionals and the final restorations.
A subsequent consultation with the patient in her temporaries to evaluate for shape, form, and function, as well as additional photographs, was required. It is extremely important that comparisons and evaluations are made with models of the provisionals and the photographs, especially the full-face images, where midline contacts, incisal plane curvatures, facial contours, and any unwanted cants can be detected by referencing to the patient's face. Failure to do so at this stage can create difficulty for the laboratory to establish all of the noted parameters. In addition, discussions of shade requirements, value requirements, and levels of translucency based on tooth preparation colors are discussed at this time.
It was decided that IPS Empress® (Ivoclar Vivadent, http://www.ivoclarvivadent.us) would be the material of choice for the crowns and the veneers. The restorations were wax-injected from a silicone mold fabricated from the model of the provisionals. This wax-up required minor adjusting after the patient consultation with the provisionals in place. On reaching a satisfactory shape and contour and developing the occlusal and functional pathways, the wax restorations were pressed into ceramics as per the correct protocol required.
The seated restorations were checked under 20X magnification for any marginal imperfections and the correct interproximal contact areas were established. Facial markings illustrating reflective and deflective facial surfaces of the restorations were incorporated (Figure 14).
At this stage the restorations were inverted for visualization of the facial contours and the symmetry of the incisal negative space. After shaping, the facial developmental grooves were established along with the required surface texturing. This was also established with the use of articulating ribbon in order to visualize and confirm the required symmetry prior to any additional ceramic layering techniques (Figure 15).
With the facial contours established and confirmed visually, the incisal cutback was completed. The incisal cutback allowed for higher translucency ceramics to be applied to the more opaque substructure. It is important in every case to ensure that the internal anatomy of the restorations are anatomically correct compared to the facial anatomy of the restorations. Internally, the higher translucency and opalescent ceramics were layered on to the cutback to establish the internal window. The lower-translucency opalescent ceramics were layered over this window to mask the internal dentin forms, giving a more natural and anatomically correct incisal appearance with the presence of an incisal halo. This can be seen after final glazing and rotary polishing of the restorations (Figure 17 and Figure 18).
The restorations were checked for the appropriate chroma and value on custom composite dies in order to closely resemble the intraoral and clinical situation as best as possible (Figure 19). Final checking on additional virgin solid models was carried out, as well as a thorough check with all the patient's documentation, as it was essential to confirm that the patient's desires were being met and the restorations were ready for insertion.
Upon receiving the final restorations from the ceramist, and prior to the patient's insertion appointment, the models were inspected to ensure that the restorations were completed on dies with clear, identifiable margins. At the insertion appointment, the patient was anesthetized and removal of the temporary restorations was initiated. To remove the temporaries in a non-traumatic fashion, slices were made between the teeth to remove the effect of splinting. As teeth Nos. 7 and 8 were full coverage, they were removed with a hemostat. Teeth Nos. 9 and 10 were gently sectioned and torqued apart. All four abutments were cleaned with a sodium-hypochlorite pumice paste to ensure that all debris was removed. The two all-ceramic crowns and two veneers were tried in with paste from the RelyX™ Veneer Cement Kit (3M ESPE, http://www.3mespe.com) to ensure that the patient was pleased with the appearance of the new restorations. To avoid possible future patient dissatisfaction/buyer remorse, the author's office insists that the patient brings a spouse/friend/colleague to assess the appearance of their new restorations prior to insertion. Once the patient and companion have approved the new restorations and documentation is made in the patient's chart, then the author is comfortable proceeding with the final cementation process.
Because tooth No. 7, teeth Nos. 8 and 9, and tooth No. 10 were all of different mediums, their cementation protocol was also different. The teeth and underside porcelain surfaces for restorations on teeth Nos. 9 and 10 were prepared for veneer insertion according to the manufacturer's instructions. To ensure that tooth No. 9 was seated correctly, tooth No. 8 was placed passively for proper alignment. Excess bonding resin was removed and teeth Nos. 9 and 10 were bonded into position (Figure 20 and Figure 21). At this point, all of the excess bonding resin was removed on the lingual, subgingival, and interproximal surfaces. Subsequently, teeth Nos. 7 and 8 were cemented into position using RelyX luting cement (3M ESPE) (Figure 22). At this stage, final clean-up and adjustments were completed, ensuring that all contacts were flossed. To return the surface gloss of the four restorations, they were polished with fine and extra-fine polishing paste (Cosmedent, http://www.cosmedent.com).
At this stage, an upper alginate impression was taken for the fabrication of an Essex retainer to be worn at night. The purpose was to offer protection of the porcelain and act as a retainer to prevent any movement. The patient was instructed to do warm saltwater rinses two times per day for the subsequent week so that the gingival tissues would heal around the new restoration. The patient was then scheduled to return 7 days later for dispensing of the Essex retainer, a check of the new restorations-including removal of any leftover resin tags-and final photographs (Figure 23, Figure 24, Figure 25).
Being able to meet or exceed a patient's expectations in this high-demand, immediate-gratification environment that is characteristic of current cosmetic dental practices is proving more and more daunting. Adding to the challenges are the realistic financial realities of the day. To be able to create a treatment plan that follows clinical principles and standards of practice, that in the end benefits the patient while working within their boundaries, defines clinical success in the new millennium. It is imperative when viewing these cases, whether complex or straightforward, to address the patient's concerns and deliver an ethical recommendation in a predictable fashion.
The author has received an honorarium from Heraeus.
About the Authors
Jordan Soll BSc(Hon), DDS
Trevor Laingchild, RDT