Evaluation of Clinical Wear and Surface Roughness of Partial Restorations Produced by Additive and Subtractive Manufacturing Methods: A Split-Mouth Randomized Controlled Clinical Trial

The aim of this study is to compare the surface roughness and wear values of crowns fabricated using currently utilized 3D printing and CAD-CAM technologies. In recent years, crown restorations produced with CAD-CAM systems have been safely used in dentistry. These types of restorative materials are expected not to undergo significant wear themselves and also not to cause wear on natural teeth. Therefore, the structural resistance and hardness of the material are clinically very important. Restorations produced using 3D printing are among the latest technological developments in dentistry. Additive manufacturing has been defined by the American Society for Testing and Materials (ASTM) as "the process of joining materials layer upon layer to make objects from 3D model data, as opposed to subtractive manufacturing methodologies." 3D printers have started to be used in various disciplines of dentistry such as dental education, oral surgery, dental implantology, orthodontics, pedodontics, prosthodontics, and restorative dentistry. In restorative clinics, they can especially be used in intracoronal restorations. However, studies in this area are quite limited. The objective of this study is to evaluate the wear values using a Geomagic 3X device and the surface roughness values using a profilometer device over a 12-month period on single crown restorations applied to permanent first molars fabricated by CAD-CAM and 3D printing techniques. A total of 26 single crown restorations will be performed on first molars. Participants will be selected among individuals aged 18-50 who apply to the Department of Restorative Dentistry, Faculty of Dentistry, Çukurova University. Eligible individuals must be systemically healthy, have no periodontal attachment loss, have an indication for crown restoration, and have a natural opposing tooth in contact with the restored tooth.