Given the critical importance of dimensional accuracy in dental prosthetics, where deviations can lead to undesirable consequences for the patient, there remains a significant knowledge gap regarding how to achieve such precision when employing Selective Laser Melting (SLM) technology, particularly with materials such as titanium and cobalt-chromium alloys. The objective of this study is to gain a deeper understanding of the factors contributing to deformation during the manufacturing of complex dental restorations in order to minimize the extent of post-processing required when utilizing the aforementioned technology and materials, and as a result to establish design guidelines that can be applied in practice. To this end, two sets of artifacts were developed in which the first set consists of samples with relatively simple geometries, while the second includes structures representing simplified versions of real all on 6 dental restorations. In the case of the samples, variations in cross-sectional geometry were introduced, whereas in the more complex constructions, different reinforcement configurations were tested. Both groups were fabricated using an SLM printer from titanium and CoCr and all of the artifacts underwent thermal treatment via annealing, while only a subset of the complex constructions was subjected to additional post-processing operations. Imaging and dimensional measurements were conducted using an electron microscope, followed by a preliminary data analysis performed in Excel. The experiment comprised 14 distinct sample geometries and 20 different restoration constructions and due to the scope of the study, only a representative selection of these is presented in the results. The analysis indicates that, when designing complex restorations, it is crucial to find the balance between the rigidity and the heat dissipation surface area of the structure. Furthermore, reinforcing the ends of complex restorations is necessary to reduce deformation and thus minimize post-processing. It is also recommended to reduce functional dimensions by no more than 2% for dimensionally more stable titanium, and by up to 3% for CoCr.
