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

Inclusion Criteria: * Adults aged 18 to 70 years * Absence of active periodontal disease * Good oral hygiene (O'Leary plaque index \<20%) * Absence of parafunctional habits (e.g., bruxism, onychophagia) * Endodontically treated first molars (maxillary or mandibular) with extensive Class II cavities and loss of at least one cusp, requiring onlay or overlay restoration * Tooth with functional occlusal contact and at least one proximal contact * Referred from the Endodontics Department of Hospital San José, with endodontic treatment completed at the same institution * Ability to provide written informed consent * Ability to attend follow-up visits at 12, 24, and 36 months Exclusion Criteria: * Untreated active periodontal disease * Poor oral hygiene (O'Leary plaque index ≥20%) * Generalized active caries * Active parafunctional habits * Teeth with complete circumferential structural destruction or insufficient coronal tooth structure for onlay/overlay restoration * Subgingival margins compromising the biologic width * Known allergy to study materials * Pregnancy or breastfeeding