Evaluation of the Fit Accuracy of Removable Partial Denture Frameworks Fabricated Using Three Different Techniques: An In Vitro Study

Aim: To conduct a laboratory study to evaluate the fit accuracy of the structures of the removable partial denture frameworks fabricated by 3D printing method and the conventional method using gypsum models. Materials and Methods: Fifteen patients with partial tooth loss of a maxillary Kennedy class I. They were divided into three groups: in the first group, the removable partial denture frameworks were fabricated from chromium-cobalt using CS casting technique; in the second group, the removable partial denture frameworks were fabricated from chromium-cobalt using selective laser melting (SLM) technique; and in the third group, the removable partial denture frameworks were fabricated from poly ether ether ketone (PEEK) using Milling technique. The fabricated frameworks were injected with polyvinyl siloxane (PVS) and were pressed to produce gypsum models, and then the rubber laminas were weighted. Results: The results of the one-way ANOVA test showed that there were statistically significant differences in the average weight of the rubber laminas in the three groups, where P<0.05. The largest gap was in the group of SLM frameworks, followed by the group of CS frameworks, and the lowest was in the group of Milling frameworks which achieved the best fit accuracy to the gypsum models. Conclusions: The structures of the removable partial denture frameworks fabricated from PEEK using Milling technique achieved the best fit accuracy on the gypsum models compared with the structures of Cr-Co fabricated using another two different methods, where the accuracy was affected by the fabricating technique used.