Milled vs 3D-Printed Partial-Coverage Restorations in Endodontically Treated Molars

The goal of this clinical trial is to compare the clinical performance of Computer-Aided Design and Computer-Aided Manufacturing (CAD/CAM)-milled and 3D-printed composite resin partial-coverage restorations in endodontically treated molars. The main questions it aims to answer are: * Do 3D-printed composite resin partial-coverage restorations show similar clinical performance compared with CAD/CAM-milled composite resin restorations? * Are there differences in survival, success rates, and complications between the two types of restorations over a 3-year follow-up period? Researchers will compare CAD/CAM-milled composite resin restorations with 3D-printed composite resin restorations to evaluate their clinical performance. Participants will: * Receive a partial-coverage restoration (onlay or overlay) in an endodontically treated molar. * Be randomly assigned to receive either a CAD/CAM-milled or a 3D-printed composite resin restoration. * Attend follow-up visits at 12, 24, and 36 months. * Undergo clinical evaluations by two blinded evaluators using the revised FDI criteria and standardized photographic documentation.