CAD/CAM - international magazine of digital dentistry

30 I I industry report _ anatomic shell technique _Abstract Challenges in aesthetic dentistry frequently in- volveachievingnaturalandlifelikesurfacetextures andensuringthepredictabilityofthefinalaesthetic results. This article presents the anatomic shell tech- nique (AST), which uses flowable composite resin shells as temporary veneers to guide the fab- rication of the final restorations and to predict the aesthetic and morphological outcomes using CAD/CAM technology. _Introduction Lack of predictability regarding the final aes- thetic outcome of CAD/CAM restorations is one of the major concerns among dental professionals, particularly in complex cases involving reconstruc- tion using multiple units. Unfortunately, there is limited literature available on this topic. This article presents a technique in which light-cured flowable composite resin shells are used as temporary veneers prior to the final restoration to predict the aesthetic and morphological outcomes using CAD/CAM technology. A clinical case is used to describe and illustrate the clinical steps.1 One of the challenges in aesthetic dentistry is achiev- ing natural and lifelike sur- face textures.2 Surface tex- ture directly influences the colour value and saturation and the zones of light reflec- tion and absorption. An ante- rior restoration that does not exhibit a surface texture and lustre that is comparable to the adjacent natural teeth will immediately appear to be outofplace,particularlywhen thesurfaceofthesurrounding dentitioniscomplexorheavily textured. The natural tooth surface is composed of hori- zontalandverticalconcavities CAD/CAM 2_2013 Figs. 1a–d_The images show the frontal view of the clinical situation. Note the inadequate restoration on tooth 21 and the dark aspect of both tooth 11 and tooth 21 (a & b). Frontal view before and after the temporary restoration was fabricated for tooth 21 (c & d). The temporary crown was made with a lighter shade to create a more suitable substrate for theaestheticevaluationaftercomposite resin shells had been placed. Note the dark substrate of tooth 11. Improving aesthetics in CAD/CAM dentistry – anatomic shell technique Authors_ Drs Nelson RFA Silva & Paulo Kano, Brazil, Dr Eric Van Dooren, Belgium, Dr Cristiano Xavier, Brazil, Dr Jonathan L. Ferencz, USA, Emerson Lacerda, Brazil Fig. 1c Fig. 1a Fig. 1b Fig. 1d