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24 RESTORATIVE Dental Tribune Middle East & Africa Edition | 5/2017 From digital planning to the mock-up and final restoration Presentation of a modern work concept on the basis of a veneer fabrication By Dr Cyril Gaillard and Dr Jérôme Bellamy, France The demand for cosmetic treat- ments is also increasing in dental practices. Today’s communication media provide patients with virtu- ally limitless access to a wealth of information on this topic. And with it comes an increase in expectations. This can pose a conundrum to the dentist: patients want to be prom- ised the desired results yet they should not be given undue expecta- tions in the run-up to the treatment. The challenge One of the challenges in day-to-day dentistry is the fact that the mock-up presented to the patient is produced from a wax-up and is often not con- sistent with the final outcome of the treatment (e.g. ceramic veneers). Several research studies have been initiated to overcome this problem. The SKYN concept is a result of this research. The solution The SKYN concept is based on a unique approach: it uses natural tooth shapes to create a mock-up di- rectly in the patient’s mouth. A wax- closely. The patient had a high smile line. However, the fact that her gums were visible when she smiled and her upper lip was asymmetrical did not bother her (Figs 1a and b). The periodontal apparatus was healthy. The soft tissues did not show any signs of abnormalities either. Treatment planning We recommended the patient to have the anterior region restored with veneers stretching from teeth 15 to 25 and advised her to have the pre- molars included in the restoration to achieve a harmonious appear- ance. The patient agreed with our proposal. We drew up the following treatment plan: • Wax-up using composite ve- neers to reproduce the natural shape and texture of the teeth • Mock-up according to the SKYN concept using a light-curing nanohy- brid composite (IPS Empress® Direct) • Intraoral digital data scan of the mock-up • Preparation of the teeth with the help of the mock-up • Digital impression of the prep- aration using an optical camera • Fabrication of the temporaries • Machining of the glass-ceramic “Never promise what you can’t deliver!” Particularly when undergoing esthetically motivated dental treatment, patients should be given a realistic visualization of the final outcome to avoid raising undue expectations. up is created on the basis of tooth shapes that reflect the anatomy and morphology of natural teeth in terms of height, width, cur vature and surface texture. The predictability of the result is ensured by using CAD/ CAM tech- nology to scan the mock-up, make adjustments in the oral cavity and then mill the veneers to achieve life- like results. The reproducibility of the mock-up and the accuracy of the result arise, among others, from the perfor- mance of the Furthermore, the res- torations present an accurate copy of the esthetic wax-up. The different working steps involved in the SKYN concept are demonstrated below on the basis of a clinical case. Clinical case Preoperative situation The patient visited the practice with a request that mainly concerned esthetic criteria. She felt that her an- terior restorations looked too yellow- ish and their shape did not fit in. The restorations had been in her mouth for several years. They should now be replaced. First, a series of digital pictures was taken to examine the situation more veneers (IPS Empress CAD) • Incorporation of the veneers Fabricating the wax-up The aim of the ceramic veneers was to give more volume to the teeth. The teeth should appear stronger and longer. Adjusting the dental pro- portions was requisite to creating a harmonious appearance between the teeth and the smile on the pa- tient’s face. To create the wax-up, we used the SKYN models (“Ante- rior Model Set” by Dr Jan Hajtó) as reference (Fig. 2). This is a reproduc- tion of natural teeth. Upon request by the patient, tooth selection was performed with the help of both the DSD program (Digital Smile Design) and the VisagiSMile design and visu- alization software. Transfer to the mock-up We created a silicone key of the ves- tibular surfaces with the help of the wax-up and applied a thin layer of composite material into the key us- ing a spatula (IPS Empress Direct) (Fig. 3). Once light cured (Bluephase® with Polywave® LED), the resulting composite veneers for teeth 15 to 25 were placed on the model and sta- bilized with wax (Fig. 4). Once the wax-up was finalized, it was dupli- cated and cast in stone. We created a silicone key from this model to assist FIg. 1a and 1b: Preoperative situation. Severely stained restora- tions in the upper anterior region. It does not bother the patient that her upper lip is asymmetrical and her gum line is visible when she laughs. Fig. 2: SKYN models (according to Dr Jan Hajtó) for the fabrication of the wax-up Fig. 3: The composite (IPS Empress Direct) is applied into the sili- cone key. Fig. 4a: The composite veneers created with the help of the sili- cone key show a natural shape and surface texture on the model. Fig. 4b: The composite veneers created with the help of the sili- cone key show a natural shape and surface texture on the model. Fig. 5 and 6: The mock-up is placed in the mouth. The surfaces are being reworked slightly. Completed mock-up. Photos and videos are used to assess it. Fig. 7a and 7b: The surfaces of the mock-up are being reworked slightly. Fig. 8: Targeted preparation of the teeth with the mock-up in place the dentist in the preparation of the teeth. The silicone key was created in two steps using two different sili- cone materials, one with a high hard- ness (Silico Dur, Cendres+Métaux) and the other with a low hardness (3M ESPE Express). The silicone key served to create the mock-up and the temporaries. Tooth preparation and data transfer to the lab The mock-up was inserted with the help of the sili- cone key and the surface texture was reworked using a polishing system (Astropol®) (Fig. 5). The esthetic ef- fect was validated with photographs and videos. The patient could also in- spect the pictures (Figs 6 and 7). Then, the teeth were prepared using a ball-shaped bur whilst the mock- up was in place (Galip Gurel 2003) (Fig. 8). This procedure meets the requirements of minimally inva- sive dentistry. An impression of the prepared teeth (Fig. 9) was taken us- this point, is ing an intraoral scanner and the t e m p o r a r i e s were fabricated with the help of the silicone key. At the dentist required to take two optical impres- sions: first, an impression of the prepared teeth and, second, an im- pression of the temporaries in the mouth. In addition, a conventional silicone impression of the prepared teeth is taken. The dental technician Fig. 9: Close-up of the prepared anterior teeth will use this impression to produce a physical model to check the fit and contact points of the milled ceramic veneers. ÿPage 26 CAD/CAM technologies have brought about a revolution in dentistry. They enable the efficient manufacture of customized ceramic veneers with high accuracy and within a short period of time. Fig. 10: The CAD data of the digital impressions of the prepared teeth and the mock-up are superimposed. Fig. 11: Veneers ready for placement Fig. 12: Restorations on the model after CAD/CAM-supported fab- rication of the ceramic veneers