Purpose: To compare the effect of thermomechanical aging on implant abutment color change when using different abutment backgrounds.
Materials and Methods: In this study, three separate experimental groups (n = 10) with different implant abutment materials were used: zirconia, modified polyether ether ketone (MPEEK), and polyether ketone ketone (PEKK). Equal-sized glass-ceramic incisor crowns were cemented to the abutments using transparent dual-curing resin cement. The specimens were then subjected to the thermomechanical aging process for the clinical equivalent of 5 years of use. The color values of each specimen in the middle third and the incisal third were recorded by a digital spectrophotometer in the CIE L*a*b* color coordinates both before and after the aging process. Color differences between groups were compared using one-way analysis of variance (ANOVA), while Tukey test was used to compare differences within the groups (P = .05).
Results: In terms of color change (ΔE00) values, the zirconia group was found to show statistically more color changes only in the middle third (P < .000), but there was no significant difference between the the MPEEK and PEKK groups. In all groups, the ΔE00 value was clinically acceptable (ΔE00 < 1.8).
Conclusion: After the aging process, high-performance polymer abutments caused less color change than zirconia. Therefore, esthetically satisfying results can be obtained in the anterior region, especially when highly translucent crown materials are used.