2. Material and Methods The in vitro investigation did not require ethical approval. However, the study was initiated after the study protocol was approved by the Institutional Review Board of College of Dentistry, Jazan University (Reference No. CODJU-22061). The material data are summarized in Table 1. A total of 160 specimens were fabricated, which were separated into subgroups based on the repair materials (PMMA and resin composite) and manufacturing methods (3D-printed and milled restorations).
