Introduction: Oxide ceramics initially found their way to medicine through the field of orthopaedics and eventually progressed to dentistry where they became prominent in the 20th century due to their excellent mechanical properties. The most commonly used oxide ceramics are based on the ZrO2 molecule and aluminium oxide. We differentiate between three types of dental ZrO2: magnesia stabilized ZrO2, alumina stabilized ZrO2 and yttria stabilized ZrO2. With the onset of CAD/CAM systems, new ways of making prosthetic dental products have also been developed. Purpose: The purpose of this graduation thesis is to study the dental ZrO2 ceramics, analyse their advantages and disadvantages, as well as getting familiar with different manufacturing processes of prosthetic dental products made from this type of ceramics. In addition, we will study how various treatments influence the microstructure and its general properties. The aim of the graduation thesis is to identify the optimal procedure for making a ZrO2 prosthetic dental product. Methods: The first part of the graduation thesis is dedicated to the theoretical background, which we acquired by examining the existing literature on ZrO2 ceramics. We studied both domestic and foreign sources found on international databases (GoogleScholar, PubMed, ScienceDirect, Elsevier, ResearchGate). Keywords that were used in this research were: dental ceramics, zirconium oxide, CAD/CAM, and zirconium oxide processing. Results: We prepared test specimens of three different ZrO2 treatments at the Faculty of Mechanical Engineering in Maribor. Then we compared the results of the tensile tests and analysed the microstructure of the processed specimens. Discussion and conclusion: Based on the tensile tests, the strength of ZrO2 ceramics is significantly affected by the sintering process. The results have shown that the pure ZrO2 ceramic has the lowest tensile strength, while the mechanically treated and sintered ZrO2 has the highest. The analysis of the sintered ZrO2 ceramic’s microstructure has shown that the interior and the exterior of the sample remained the same. On the other hand, the microstructure of the sintered and mechanically treated ZrO2 ceramic has shown more defects on its exterior. The results could be improved by another test including more specimens. In addition, the analysis of the microstructure with modified sintering parameters could include a pure ZrO2 ceramic.
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