Evaluation of the Impact of Surface Modification with Air Abrasion (sandblasting) and Ultraviolet Radiation on the Retention Strength of Polyetherether Ketone (PEEK) Coping in Relation to the Underlying Dentin Abutments: An in vitro Study

Abstract Objective: The present study aims to evaluate the effect of surface modifications of polyetherether ketone (PEEK) with air abrasion (sandblasting) and ultraviolet radiation (UV radiation) on the retention strength of PEEK copings in relation to the underlying dentin abutments. Settings and Design: The present study is an in vitro study design. Materials and Methods: For the present in vitro study, 36 non-carious, intact maxillary premolars were collected, and the specimens were divided into three groups: including Group A, wherein surface modification was accomplished with air abrasion (sandblasting); Group B, wherein surface modification was accomplished using 172–308 nm UV radiation; and Group C, wherein surface modification was accomplished using air abrasion (sandblasting), followed by treatment with UV radiation. The PEEK copings, bonded to the underlying dentin abutments, were subjected to a pull-off test using the Hounsfield universal testing machine, while the maximum load (force) value, at which debonding of the copings from specimens was observed, was recorded and subjected to statistical analysis. Due to the non-normal distribution of the variables, subsequent multiple comparisons between different groups were performed using Kruskal–Wallis H -test. Also, post hoc analysis was performed using the Mann–Whitney U -test with Bonferroni correction applied to conduct pairwise comparisons among independent groups. Results: Kruskal–Wallis H -test used revealed a significant difference among all the test groups ( P < 0.001), while variations in the median retention strength values obtained were found to be statistically significant when compared between Group A and Group C specimens ( P = 0.033) and statistically highly significant between Group A and Group B, and Group B and Group C specimens ( P < 0.001) on post hoc analysis by Mann–Whitney U -test for pairwise comparisons among independent groups. Conclusion: Based on the findings obtained, it could be concluded that the median retention strength measured was highest for Group C specimens (9.045 MPa), followed by Group A specimens (8.365 MPa), and least for Group B specimens (5.36 MPa).