Comparison of marginal and internal adaptation of three-unit fixed dental prostheses produced from different metal-free materials by CAD/CAM technology

Aim: The aim of this study was to compare the marginal and internal adaptation of three unit fixed dental prostheses (FDPs) fabricated with monolithic zirconia (MZR), polyetheretherketone (PEEK), polymer composite (COMP), polyetherketoneketone (PEKK) and fiber reinforced composite (FRC) materials by CAD/CAM method. Materials and Methods: A total of 100 three-unit fixed dental prostheses were fabricated from MZR, PEEK, COMP, PEKK and FRC materials by CAD/CAM method (n=20). Marginal and internal adaptation values of the produced prostheses were measured using the silicone replica method at x40 magnification under a stereomicroscope. Obtained data were analyzed using one-way analysis of variance and Tukey HSD test (p<0.05). Results: The marginal and internal adaptation values of the MZR group were found to be statistically better than all other groups (p<0.001). There was no statistically significant difference found between PEEK, COMP, PEKK and FRC groups (p>0.05). Conclusion: The marginal and internal adaptation of the MZR group was found to be better than the others, and the marginal-internal adaptation values of all groups were found within clinically acceptable limits. Key Words: CAD/CAM, FRC, Internal Adaptation, Marginal Adaptation, PEEK, PEKK, Zirconia