Comparison of PEEK (polyetereterketon) frameworks and other framework materials presented as an alternative to the framework materials used in fixed prosthetic restorations in terms of marginal adaptation and surface properties

Purpose: In this study, it was aimed to compare the marginal adaptations of metal frameworks, frameworks produced by PEEK (Polyetheretherketone), zirconia, direct metal laser sinter (DMLS) Co-Cr produced with CAD/CAM technology. Materials and Methods: A total of 80 stainless steel stumps were embedded in silicone molds, and the main model was obtained and PEEK, Zirconia and DMLS Co-Cr frameworks produced by CAD/CAM technology and metal frameworks produced conventionally (n = 20) were divided into 4 groups. Marginal gap was measured with a stereo microscope at x20 magnification. In addition to descriptive statistics in the evaluation of the data, the one-way ANOVA was used with the Post Hoc multiple comparison test Tamhane's T2 since the data were normally distributed and variants differ according to the Kolmogrov – Smirnov and Shapiro-Wilk tests. The surface properties of conventional cast metal, Laser sintered Co-Cr CAD/CAM milling Zirconia and CAD/CAM PEEK framework materials were examined with scanning electron microscope. Results: There was a significant difference in marginal gap before and after cementation among all groups as a result of evaluations made by statistical analysis (p <0.05). Marginal gap values (µm) of pre-cementation and standard deviation; cast framework is 113,10 ± 48,03, PEEK framework is 86,07 ± 21,00, Zirconia framework is 35,9161 ± 4,06 and DMLS framework is 35,54 ± 5,04. Marginal gap (µm) values of the frameworks after cementation and standard deviation; cast framework was 121,30 ± 48,40, PEEK framework was 96,44 ± 22,02, Zirconia framework was 42,70 ± 3,24105 and DMLS framework was 28.86 ± 14,79. Conclusion: According to what was done before and after cementation, the lowest value of marginal gaps was found in the DMLS metal framework and the greatest value was found in the cast framework. Key words: PEEK; Marginal adaptation; Laser sinterized Co-Cr; Zirconia; CAD/CAM