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Table 1 Summary of the steps in the wax prototype technique. D i g i t a l w a x p r o t o t y p e s : A c l i n i c a l r e p o r t Clinical step Procedure Table 1 1 2 3 4 5 6 7 8 Preliminary impressions are taken and a traditional or digital diagnostic wax-up is made. Teeth are prepared and provisionalized based on the diagnostic wax-up and following the guidelines for the type of material chosen. A final traditional polyvinylsiloxane impression or digital impression is taken and used to design the final restorations. A traditional digital bite record in centric relation is taken to mount the case. The case is digitally designed and wax patterns are milled for verification purposes. The wax patterns are modified if needed by selective grinding or wax addition. Restorations are used to press or scan-copy-mill the final restorations. Restorations are delivered with no expected modifications required. esthetics, and the restorations were verified for marginal fit, proximal contacts and occlusion. No adjustments were needed. Implant abut- ments were torqued to the manufacturer-rec- ommended values, and the posterior resto- rations were cemented with resin cement (RelyX Unicem, 3M ESPE, Seefeld, Germany). The ante- rior crowns were bonded using resin cement (Variolink Esthetic, Ivoclar Vivadent; Figs. 9–11). The patient was very satisfied with the treat- ment outcome and was followed for a period of 6 months, during which time she reported no complications or complaints. Discussion This clinical situation illustrated a patient with a severely worn dentition who sought dental treat- ment after the maxillary anterior incisal edges had become compromised, thereby affecting esthetics. Owing to the loss of clinical crown height of the maxillary incisors subsequent to erosion and attrition, the decision was made to increase the VDO in order to provide adequate space for esthetically pleasing restorations. The patient was amenable to comprehensive fixed prosthodontic rehabilitation because of missing teeth and her inability to tolerate a removable prosthesis. The diagnostic wax-up had revealed very minor issues that the patient was not inter- ested in addressing at the time of the treatment; thus, she did not desire whitening or direct res- torations on the mandibular incisors. Traditionally, diagnostic wax-ups done by hand, by the clinician or technician, have been known to be a time-consuming step in the treatment planning process. The advantage of incorporat- ing digital dentistry into the workflow of pressed restorations is that it provides a more consistent result in diagnostic wax-ups obtained through the use of CAD libraries, instead of relying on freehand wax-ups. Additionally, the time needed for the creation of a diagnostic wax-up is signifi- cantly reduced; in this situation, the virtual wax-up was created in less than 60 min. The employment of CAD/CAM to create a milled wax prototype of the final restorations is a revolutionary use of the technology for both dentists and dental technicians. Not only can it be used as an esthetic and functional try-in tool by the clinician to verify marginal adaptation, occlusion and esthetics prior to delivery of the final restorations, but it also can serve as essen- tially a wax pattern for the fabrication of pressed or metal–ceramic restorations or a scan copy for milled restorations if any modifications are made. The wax used in CAD/CAM milling discs is very different than traditional dental wax. In order to resist the heat produced by the burs during milling, these waxes are developed as a hard hybrid plasticized wax blend, with a melting point between 101.667 and 121.111 °C.14 During try-in, the shape, marginal fit, occlusion and proximal contacts of the restorations can be verified, because the rigidity of the wax allows for this. If adjustments are needed, the wax can be modified accordingly with heat or rotary 46 Volume 3 | Issue 4/2017 Journal of Oral Science & Rehabilitation