Introduction: The production of a metal base for fixed prosthetic dental protheses is a demanding process because every product should tightly fit into the preparation. The fabrication process affects the roughness of the metal base surface, how it fits the construction, and the retention forces. Poor production quality may result in improper fitting and consequently medical complications. Purpose: The purpose of this thesis is to make an overview of the existing literature on the comparison of accuracy of the metal base fabrications for conventional metal ceramics restorations and the SLM technique. Based on the acquired facts, the comparison of the accuracy of both techniques was made in the fabrication process for a metal-ceramic bridge 31-37. Methodology: The theoretical part of the thesis is based on the existing scientific publications. The literature was accessed through COBISS, Google Scholar, and Medline. The practical part of the thesis was conducted in the dental laboratory. A digital comparison of metal half products was made using Blender2.8, GOM Inspect 2018, and Adobe Photoshop CC. Results: An image comparison of both constructions was made on the control model and without a model; a cervical thickness of constructions was measured at the predetermined locations, both constructions were scanned and compared with a dedicated software. The digital comparison of the CAD file and the SLM construction is a standard analysis regularly carried out using optical scanning. When comparing the SLM and the cast construction, the SLM construction was used as a static reference. The SLM construction was overlaid with the cast one using the global best-fit alignment and a colour map of the deviations was drawn. Discussion and conclusion: The aim of the thesis is to determine the differences in the accuracy of the metal base for the metal ceramics technique when using the digital or the manual modelling technique. To understand our comparison, the in-depth knowledge of the digital and manual fabrication processes for metal bases is required, and this process is also discussed in the thesis. We concluded that the fabrication accuracy greatly depends on the skills of laboratory practitioners. The manual technique requires more phases, and the modelling process for larger constructions is significantly more time-consuming. On the other hand, using a digital technique, the base can be made several times when required, while no additional time is spent on remodelling, which is the biggest advantage of this technique. We also realized that a quality comparison requires access to dedicated equipment and standardized as well as proven analytical techniques.
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