Comparison between five CAD/CAM systems for fit of zirconia copings

Habib, Syed Rashid / Al Otaibi, Asim Khaled / Al anazi, Talal Ali / Al anazi, Samer MoslehPage 437 - 444Objective: The aim of this in-vitro study was to investigate the marginal and internal fit of zirconia copings fabricated by five CAD/CAM (computer-aided design/computer-assisted manufacture) systems.Method and Materials: A typodont mandibular right first molar was prepared according to ideal parameters for a zirconia crown, scanned digitally, and 100 identical resin dies fabricated by 3D printing. Samples were randomly divided into five groups and sent to CAD/CAM systems for zirconia copings (A, Ceramill-Motion 2, Amann Girrbach; B, Weiland, Ivoclar Vivadent; C, Cerec, Ivoclar Vivadent; D, Prettau Zirconia, Zirkonzahn; E, Cad4dent). CAD of the copings included standardized cement space of 30 µm and CAM was carried out. Copings were tried/adjusted on the respective dies and embedded under a standardized load of 20 N in self-curing resin. Samples were sectioned mesiodistally into two halves. Marginal and internal gap values were measured with a digital microscope at 50 to 200 × magnific ation at nine sites.Results: The lowest and highest mean gap values of 46.93 ± 13.50 and 101.65 ± 35.56 μm were found for Group A and Group D, respectively. ANOVA showed a statistically significant difference between the mean values of all the groups (P = .000). Multiple comparisons with post hoc Tukey test indicated a statistically significant difference (P
Source: Quintessence International - Category: Dentistry Source Type: research