# Four Different Build Angles in 3D-Printed Complete Deture Bases: A Comparative In Vitro Study
## 4 Discussion
However, the exact definition of the build angle can vary, as the orientation of the object relative to the build platform is not standardized across studies. This variation highlights the need for a more precise definition of build angle. In this study, a 0\({}^{\circ}\) build angle is defined as the orientation where the plane formed by the major axis and the second major axis of the 3D-printed product is parallel to the build platform. Then, the build angle is defined as the acute angle between the build platform and the major axis-secondary major axis plane when the anterior part of the printed product is elevated. Conversely, if the posterior part of the printed product is elevated, the build angle can be considered as the obtuse angle. For products with both upper and lower surfaces, defining the 0\({}^{\circ}\) build angle as the orientation when the lower surface is parallel to the build platform could serve as a universal standard for determining build angles in future studies. This study had some limitations. The number and position of supports that needed to be removed, which were automatically generated on the reference points on the polished surface, were different for each sample. Moreover, in this study, only four different build angles were evaluated, and the tissue surface of the denture base could have been divided into several parts for RMSE calculation. Additionally, the number of specimens used in the study was small, although it slightly exceeded the calculated sample size. For the sample size calculation in the present study, we based the number of specimens required on studies with relatively larger effect sizes, which may have posed a limitation. Among the studies referenced in this research that investigated the relationship between build angle and the accuracy of denture bases, the absolute values of effect sizes ranged from 0.005 to 3.901. On the contrary, choosing a larger sample size would undoubtedly have increased the statistical power of the analysis and allowed for a more precise evaluation of between-group differences in tissue adaptation and reference point distances. In addition, it would have resulted in more accurate estimates of effect sizes and narrower confidence intervals; thus, it would have enhanced the reliability of the findings and provided a stronger foundation for future studies. Yet, our decision regarding sample size was dictated by practical constraints. The evolution of materials and printing technologies may play a crucial role in overcoming the observed discrepancies related to build angles in the 3D printing of dentures. As noted, the SLA 3D printer was associated with certain issues, and future research should explore the use of advanced printing technologies or alternative resin materials that could mitigate these issues. This study emphasizes the importance of having a standardized definition of build angles, advocating for the development of an international standard that ensures consistency across various studies. Such standardization would significantly contribute to the more reliable translation of research findings into clinical practice. Moreover, as the results of this study are clinically significant, it is essential to consider how these findings can be implemented in a real-world clinical setting. This necessitates further studies to evaluate additional factors that may influence the clinical application of these findings, such as patient comfort, durability of the dentures, and ease of the fabrication process.