Advancements in 3D-Printed Technology and Digital Workflows in Dentistry: Investigations into Occlusal Accuracy and Resin Performance for Prosthodontic Applications

Digital technologies have sparked a paradigm shift in dental practice, enabling increasingly precise diagnostic and restorative procedures. Among these innovations, additive manufacturing—commonly referred to as 3D printing—has garnered significant attention for its potential to streamline the fabrication of dental casts, provisional and permanent restorations, and other prosthodontic components. Advancements in computer-aided design/computer-aided manufacturing (CAD/CAM) further enhance customization and reduce material wastage. However, key questions remain regarding the accuracy and durability of 3D-printed prosthetic components, as well as the clinical variables that may compromise their performance. The translation from virtual design to physical object, while efficient, can introduce dimensional inaccuracies. Occlusal fidelity, marginal adaptation, and vertical dimension maintenance are paramount for long-term prosthodontic success. Furthermore, the inherent phenomenon of mandibular flexure during mouth opening raises concerns about cross-arch discrepancies in rigid prostheses, particularly those supported by implants lacking the shock absorption provided by a periodontal ligament. This thesis is based on research conducted at Tufts University School of Dental Medicine. Our team addressed three interrelated research domains. First, it investigates how different mounting protocols—specifically hand articulation versus CAD-generated articulation pins—affect the accuracy of occlusal relationships in 3D-printed dental casts. Second, it examines the marginal accuracy and internal fit of novel 3D printing resins for permanent restorations compared with conventional milled zirconia. Finally, the thesis explores the clinical impact of mandibular flexure on digital scanning workflows, highlighting implications for cross-arch fixed restorations. By integrating these findings, this work aims to provide a scientifically grounded framework for dentists and researchers seeking to optimize 3D printing protocols, resin materials, and clinical procedures to achieve durable and precise prosthodontic outcomes.