Evaluation of the marginal fit of finish line designs of novel CAD/CAM restoration materials

Aim: The purpose of this study is to compare the marginal fit crowns manufactured using different CAD/CAM materials on 2 types finish line design.Material and Method: Tooth preparations were made by creating lines (rounded shoulder, chamfer) an acrylic mandibular second premolar model. Impressions taken each preparation polyvinylsiloxane impression material, blocks with three compositions including lithium disilicate (LDS), zirconia-reinforced silicate (ZLS), monolithic zirconia (MZ) (UP.CAD, Celtra Duo, VITA YZ HT) produced a (computer-aided-design computer-aided-manufacturing) milling device (VHF R5) (n=10). gap values crown restorations measured same operator stereomicroscope (LEICA DVM6). Histogram plots Kolmogorov-Smirnov test used normality distributions variables. non-normally distributed (nonparametric) variables compared Mann-Whitney U for two groups Kruskal-Wallis more than groups.Results: between designs separately material. Accordingly, rounded shoulder smaller those chamfer in all materials. also among type. HT material Duo (ZLS) UP.CAD (LDS) both designs. There was no significant difference UP.CAD.Conclusion: design factor that affects fit. Monolithic appropriate clinical use as it shows better LDS ZLS.