Long-term Effect of Adhesive Systems on Resin Composite Repair of 3D-Printed Polymers for Temporary Fixed Dental Prostheses

Objective : The aim of the present study was to evaluate the effect of adhesive systems on the bond strength of composite resin repairs to 3D-printed polymer material used in temporary fixed dental prostheses. Materials and Methods : Block-shaped specimens of 3D-printed polymer materials used in temporary fixed dental prostheses (priZma 3D Bio Prov) were obtained using a Photon Mono 6K 3D printer (Anycubic) and subjected to post-curing processing (Wash&Cure 2.0, Anycubic). Composite resin restorations were fabricated on these blocks in two 2-mm increments. The following experimental groups were created: three-step conventional adhesive and universal adhesive system groups (n = 5). Sticks with an adhesive area of 0.5 mm² were obtained using a precision cutting machine, and microtensile bond strength was evaluated after 24 hours and six months. Data were analyzed using a t-test between groups and paired t-test between times with a significance level of 0.05, using SigmaPlot Statistical Software. Results : The μTBS values varied from 28.42 ± 4.12 MPa to 43.29 ± 2.68 MPa. The three-step conventional adhesive yielded a higher microtensile bond strength (μTBS) than the universal adhesive system when tested after 24 hours (p = 0.01). However, after 6 months, no significant difference in μTBS was observed between the three-step conventional and universal adhesives (p = 0.07). Conclusions : It can be concluded that both three-step conventional and universal adhesive systems are effective in promoting adhesive repair between temporary 3D-printed resin and composite resin. Clinical Relevance : The findings suggest that both three-step conventional adhesive and universal adhesive systems can be reliably used for the repair of 3D-printed temporary restorations in clinical settings.