UNIvERSITy Of BElgRADE, fACUlTy Of DENTISTRy, ClINIC fOR PROSTHETIC DENTISTRy, BElgRADE, SERBIA

Introduction: The results of many years technological development of Cerec® 3D CAD/CAM system, is implementation one intraoral and two extraoral optical scanning methods. Aim: The aim of this study was to determine the precission of ceramic crowns made by optical scanning methods of Cerec®3D system .
Methods: The study was conducted in three experimental groups of ceramic crowns in whose manufacturing was applied three optical scanning methods of Cerec®3D system. Control group consisted of metalceramic  crowns made by conventional metodology. The accuracy of ceramic crowns was examined by measuring of the marginal gap size between edge of crowns and demarcation by scanning electron microscope (SEM).
Results: The research found, that there is a difference in the accuracy of ceramic crowns made by Cerec®3D system. The highest level of accuracy was recorded in the group of crowns made by technique extraoral optical superficial scanning (31,64±9,45µ). Marginal gap size crowns made with technique intraoral optical superficial scanning showed a lower level of accuracy (50,27±31,50µ). Value of marginal gap size crowns made by technique extraoral laser point scanning was  102,58+31,23µ.
Conclusion: Ceramic crowns made by Cerec®3D optical

Key words: Cerec, Computer-Aided Design, ceramic, crowns, marginal adaptation.