The Impact of Sintering Technology and Milling Technology on Fitting Titanium Crowns to Abutment Teeth—In Vitro Studies

Abstract

Introduction: The aim of the study is to evaluate the marginal and internal fit of titanium alloy (Ti6Al4V) crowns using the Selective Laser Melting (SLM) method and CAD/CAM milling. Materials and Methods: The research materials are abutment teeth and prosthetic crowns. The method is based on scanning the abutments and the interior of the substructures, creating their 3D models, using the program for comparison, and determining error maps of fitting crowns to the reference models, in the form of positive and negative deviations. Adding the deviations gives information about the tightness of the crowns. The Shapiro–Wilk test and the one-way ANOVA analysis were performed. The level of significance was p = 0.05. Results: The crowns made in SLM, a slightly better internal fit was found than for milled crowns, as well as a comparable marginal fit. The mean deviations for the sintering were the values [mm]: −0.039 and +0.107 for tooth 15 and −0.033 and +0.091 for tooth 36, and for the milling –0.048 and +0.110 for tooth 15 and –0.038 and +0.096 and for tooth 36. Conclusion: Based on the research conducted and the experience in therapeutic procedures, it can be indicated that the fitting of titanium alloy crowns in SLM and milling meets the clinical requirements. To evaluate the technology, a method was developed that determines the accuracy of mapping the shape of the tooth abutments in the crown substructures for the individual conditions of the patient.