April 1, 2015
by Jordan Soll, BSc (Hon.), DDS, Dip. ABAD
The cover model for Oral Health’s first Cosmetic Dentistry issue in April 1999, beautifully displays the calibre of dentistry that could be achieved at that time utilizing a multidisciplinary approach. However, any dental restoration, no matter how well it is placed, will experience the ravages of time given the hostile environment of the oral cavity and the calibre of materials that were available when they were placed. In addition, the habits of the individual can have a major impact on the longevity of the restorations, which in this case were veneers. Specifically, the patient was a strong grinder with only periodic wearing of her night guard. After 16 years of excellent service, the Feldspathic veneers began to deteriorate and the patient came to the realization that two fractured veneers within a one month period, were the motivation to consider how current concepts in preparation, materials and design could improve upon what was a pleasing past.
As dentists, we sometimes associate our successful cases with personal events in our lives, as a way of recalling the length of time that has passed from when we first completed the work. In this particular case, I will always remember the timing, as I had to postpone the insertion-completion due to the birth of my daughter that day. After 16 years I have been through a lot with my daughter (as any father of a girl can attest), however the veneers had begun to show their age and the patient requested an update (Fig. 1a, Fig. 1b, Fig. 2a, Fig. 2b).
The patient is now 52 years of age, and is healthy with no contributory medical abnormalities. As I had been seeing the patient for the past 17 years for preventative and restorative dental care as needed, I was confident that there were no underlying dental concerns. Moreover, as this case involved primarily replacing the existing restorations, a full aesthetic work up was not required, as I was the primary clinician on the original work. Although extensive crown lengthening was done 16 years ago, it was noted that tooth #11 did not have the same gingival crest as tooth #21 and it was suspected that this most likely occurred as a result of altered passive eruption (Fig. 2a).
Since the patient did not want to experience flap-involved crown lengthening, the use of a soft tissue laser enabled a clinically acceptable result without compromising the biological width. After 14 days to allow for soft tissue healing, the patient was ready to proceed with her treatment.
At this appointment, no pre-operative medication was dispensed and the patient was anaesthetised with Septanest 1:100,000 Epinephrine. As the procedure would take many hours, only 3 teeth were anaesthetised at a time to avoid local anaesthetic toxicity. Beginning with tooth #25, each veneer was removed and the preparations were mildly refined ensuring that any hint of the previous resin cement was removed. When preparing tooth number’s 23, 22, 21, 11, 12, 13 the contacts between the teeth were now separated and the finish lines were now finished at the Mesial-Lingual and Distal-Lingual. This is a departure from how the anterior veneers were prepared 16 years ago. This change ensures an excellent emergence profile and allows for a more predictable contact between the teeth. Should any staining at the margin interface occur, it would be restricted to the lingual of the anterior teeth (Figs. 3a, 3b). Once all the teeth were re-prepared ensuring the removal of all previous porcelain, and all new margins to follow the existing gingival contours were .5mm into the sulcus, all corners and line angles were rounded using a coarse disk.
Prior to taking the impression, a stump shade was recorded and a photo was taken. These were sent to the ceramist to allow for any block out that may be required to prevent any shine through (Fig. 4). When the original preparations were done, # ooo non- impregnated cord was placed into the sulcus to ensure a perfect impression. To avoid mechanical manipulation of the sulcus, thereby possibly avoiding premature recession, 3M Gingival Retraction Paste (3M Corporation Minneapolis, MN) was used to control moisture and seepage, ensuring that there was adequate exposure of the finish line so that the complete marginal detail could be captured. After three minutes, the retraction paste was washed off with copious amounts of water, and the preparations were dried. The preparations were impressed using Impergum (3M Corporation Min
neapolis, MN) medium body for both the flowable around the margins and the tray material. Once the tray was removed, the impression was inspected to ensure that all details were captured. To register the occlusion, an interocclusal registration was taken. Subsequently, the Kois Facial Analyser was used to record/register the position of the maxilla, allowing for easy transfer of information to the ceramist. At this stage the Impergum impression, opposing arch alginate, facial and occlusal registrations, and laboratory script instructions were prepared and boxed for the lab. The digital photo of the stump shade was emailed. The preparations were now ready to be temporized.
Unlike temporization 16 years ago where the temporaries were fabricated in two sections (Fig. 5) and cemented on with Rely X Temp On NE. (3M Corporation, Minneapolis, MN), these temporaries were fabricated directly to the preparations utilizing a stent fabricated from the diagnostic wax-up. The process began by spot etching the prepared teeth with a 37% phosphoric acid (Fig. 6). The etch stayed on the teeth for approximately 10 to 20 seconds and was washed off with a copious amount of water and was then air-dried. The preparations were coated with an unfilled resin (Cosmedent, Chicago, IL), to allow for the restorations to be semi retentive, and then cured for 20 seconds (Figs 7,8). Using the stent fabricated from the wax-up, the buccals surfaces were filled with Filtek Supreme Flowable (3M Corporation, Minneapolis Mn.) (Fig. 9). The stent was seated in the mouth and the preparations were cured through the clear stent (Fig. 10). After the restorations were cured on the buccal and lingual, the stent was removed and the margins and embrasures were cleared away using a Brassler Esthetic trimming bur (Fig. 11). The temporaries were refined and polished, and the occlusion adjusted and checked for interferences that may have caused them to prematurely break (Figs. 12a, 12b). Prior to dismissal, the patient was instructed to only eat soft foods, as the temporaries must be treated with care. In addition the temporary veneers were attached and they cannot be flossed. It was also recommended to use a warm saltwater rinse to promote healthy gingival tissues.
Prior to seeing the patient for the insertion appointment, the laboratory-fabricated eMax veneers (Ivoclar, Amherst, N.Y.) were checked on the solid model to ensure that the marginal adaptation was co
rrect and there were no surface imperfections. When the patient attended for insertion of the permanent veneers, the gingival tissues were inspected to ensure that there was no inflammation from the provisionals. Unlike the preparation appointment, the patient was anaesthetized from tooth numbers 15 to 25 to allow for the immediate try-in of all 10 veneers. The temporary veneers were sectioned through the interproximals from tooth numbers 13 to 23 for individualization, allowing for easier removal. The premolars were sectioned to the contact point. Once the provisionals were removed, the surfaces were buffed with a coarse disk, and then scrubbed with pumice and sodium hypo-chloride to disinfect them. The veneers were then tried on with Try-In paste, part of the Rely X Veneers Cementation kit, allowing for simulation of the cement without concern for premature curing of the cement (3M Corporation Minneapolis, MN). Once the patient previewed the veneers in place and approved the appearance, the veneers were removed and cleaned with alcohol to remove any residual of the Try-In paste. The abutments were again scrubbed with pumice and sodium hypo-chloride to ensure a clean bondable surface. To prepare for the insertion phase the veneers were treated with porcelain etch for 60 seconds rinsed with copious amounts of water, silaned, and a coated with filled bond, but not cured. This system, which is part of Rely X Veneer cementation kit, is preferred by the author, as it avoids curing the bonding resin on the veneer or on the abutment prior to cementation of the restoration, and avoids any film thickness issues.
Cementation was initiated by etching all prepared surfaces of tooth number’s 13 to 23 for 10 to 15 seconds, then washing off with copious amounts of water and then lightly air dried leaving a moist surface. The etched teeth were then scrubbed with Single Bond and not cured (3M Corporation Minneapolis, MN). The veneers were filled with translucent veneer cementation paste and placed in tooth number’s 11, 21, 22, 12, 23, 13 fashion. The excess material was removed and the contacts were lightly flossed. Once the clean up was complete, teeth 13 to 23 were fully cured. The same sequence was performed for tooth numbers 24 to 25 and 14 to 15. After all visible resin tags were removed, using a horseshoe articulation paper; the occlusion was checked and adjusted in CO, and right and left excursions. At this time, all margins were checked by tactile sensation with an explorer to ensure that there were no resin tags that were undetected by magnification. Following this, the final restorations were polished with a two stage diamond polishing paste and then rinsed off with copious amounts of water (Cosmedent, Chicago Ill.) Prior to dismissal, upper and lower alginate impressions were taken, along with an Aqualizer occlusal registration (Jumar Corporation, USA) for the fabrication of a Maxillary night guard. The patient was then instructed to continue to use warm saltwater rinse once a day and if any interferences were detected to advise my office as quickly as possible so that the appropriated adjustment could be made. A follow up appointment was made one week later for insertion of the night guard and final photographs.
The patient attended one-week post insertion for the final evaluation. The Maxillary night guard was tried in, and minor occlusal adjustments were made to ensure that the guard was balanced. In addition occlusal adjustments were also required on the final restorations to give the patient freedom of movement. Inspection of the gingival tissues did not reveal any abnormalities and the patient was free of sensitivity. At this time, final photographs were taken (Figs. 13a, 13b, 13c, 14a, 14b, 15a, 15b).
FIGURE 14A. Completed full face view 1998.
FIGURE 14B. Completed full face view 2014.
No matter how well a project is conceived and executed, there are few things that span the test of time, especially when there are abnormal forces acting on the dentition. Moreover, we cannot be a part of our patients’ lives to observe that the post-operative instructions are followed on a daily basis, including the daily wear of protective appliances. As such, the author is pleased with the longevity that the original restorations provided. Combined with the up to date preparation techniques, materials and patient compliance, I am confident that the patient will achieve tremendous value and longevity with her new veneers.
The author would like to acknowledge Mr. Trevor Langchild of Yorkville Dental Studios for his outstanding restorations.OH
Dr. Jordan Soll is a Diplomate on the American Board of Esthetic Dentistry and Co-Chair of the Editorial Board of Oral Health.
Oral Health welcomes this original article.