Supervisor : Lamia sayed Kheiralla, Rana Mahmoud Sherif.ELSayed, Alaa Hamed,2022-01-172022-03-272022-01-172022-03-272017.EG-CaMIUThs253https://iorep.miuegypt.edu.eg/handle/20.500.13071/76DISSERTATION NOTE-Degree type M.Sc.DISSERTATION NOTE-Name of granting institution Misr International University, Faculty of Oral and Dental MedicineIncludes bibliographic references (p. 123-142)`Includes summary in Arabic.Color matching and long-lasting color stability of dental materials are two of the major factors that influence the success or the failure of any esthetic dental restoration. In addition, the surface texture of a tooth colored restoration has a major effect on plaque accumulation, discoloration, wear and the esthetic appearance. Ideally, for any material to be used, it should fulfill four main criteria; esthetics, strength, accuracy and passive fit. Dental ceramics set ground as the most natural in appearance, texture, color, reflectance, and translucency, where distinguishing them from the natural teeth is sometimes even impossible. Moreover, it was approved that ceramics have optimum biocompatibility to oral tissues and reduced tendency of maintaining bacterial plaque as well as it does not absorb water nor conduct heat. A Computer Aided Design/Computer Aided Manufacturing (CAD/CAM) was introduced to dentistry in the mid-1980s. Several types of CAD/CAM ceramic blocks have been developed for restoration fabrication, including feldspathic ceramic, leucite-reinforced ceramics, lithium disilicate ceramics, and zirconium oxide ceramics. CAD/CAM offer high esthetic demands, short chair side time, and less number of visits. Although dental ceramics are widely used for inlays, onlays, single crown and fixed partial dentures, they still have some disadvantages, such as high cost, the risk of fracture due to their brittleness, high wear to the opposing natural dentation, handling concerns (fragility during trial insertion and cementation) and veneer failure. Therefore, there has been an increasing interest in the use of newly introduced hybrid ceramic blocks to overcome some of dental ceramics drawbacks, due to their optimal resilience, stiffness, and wear characteristics together with their excellent esthetics. Currently, there is no much documentary evidence available regarding the effect of the different oral media on the milled CAD/CAM hybrid ceramic regardless to glass ceramic restorations. Thus, it was worthy to investigate the color stability and surface roughness of a recently introduced CAD/CAM hybrid ceramic (CERASMART) to lithium disilicate (IPS e.max CAD) ceramic under two beverage solutions (coffee – Mirinda orange juice) and a home-bleaching agent.142 pages : illustrations ; 30 cmtextapplication/pdfengFixed ProsthodonticsBridges (Dentistry)text