## 3 Results  
The results of the three-way ANOVAs of standard gray resin and MAZIC D resin are presented in Figures 3 and 4. The three-way ANOVA of standard gray resin for the RMSE  
Figure 2: Flowchart of the overall experimental process of this study. The accuracy was evaluated according to the three-dimensional (3D)-printing material used, whether the support structure was removed, and the postcuring time. values between the modeling and scan data after the postcuring process confirmed that the dimensional changes were significantly affected by whether the support structure was removed (\(F\) = 17.317, \(p\) < 0.001), the arch position (\(F\) = 567.555, \(p\) < 0.001), and the postcuring time (\(F\) = 9.755, \(p\) < 0.001) (Figure 3). The accuracy was higher for the group in which the support structure was present during the postcuring process than for the group without support and higher for the maxilla than for the mandible. The error increased gradually with the postcuring time during the process of polymerization of the unpolymerized residual resin. However, there were no significant interactions between support removal and arch position (\(F\) = 2.151, \(p\) = 0.144), support removal and postcuring time (\(F\) = 1.295, \(p\) = 0.274), or arch position and postcuring time (\(F\) = 0.805, \(p\) = 0.523), nor between all three factors (\(F\) = 0.268, \(p\) = 0.898). The three-way ANOVA of MAZIC D resin confirmed that the dimensional changes were significantly affected by support removal (\(F\) = 98.774, \(p\) < 0.001), arch position (\(F\) = 191.145, \(p\) < 0.001), and postcuring time (\(F\) = 32.032, \(p\) < 0.001) (Figure 4). The accuracy was highest in the group in which the support structure was present and the maxillary group, and the error increased with the postcuring time. Significant interactions were observed between support removal and arch position (\(F\) = 66.668, \(p\) < 0.001), support removal and postcuring time (\(F\) = 8.174, \(p\) < 0.001), and among all three factors (\(F\) = 3.786, \(p\) = 0.006). However, there was no significant interaction between the arch position and postcuring time (\(F\) = 0.590, \(p\) = 0.670). Dimensional accuracy was evaluated when the same 3D printing resin was used in the same arch, and the overall results are presented in Figures 5 and 6 and in Table 2. For the maxilla base printed three-dimensionally using standard gray resin, the dimensional changes were smaller in the group in which postcuring was performed with the support structure present. The error increased with the postcuring time even in the specimen  
Figure 4: Three-way ANOVA results of RMSE values for the MAZIC D resin specimens with respect to (**A**) whether the support structure was removed during postcuring, (**B**) arch position, and (**C**) postcuring time. Data are mean and standard deviation values. ***, \(p\) \(\leq\) 0.001. Figure 3: Three-way ANOVA results of root-mean-square error (RMSE) values for the standard gray resin specimens with respect to (**A**) whether the support structure was removed during postcuring, (**B**) arch position, and (**C**) postcuring time. Data are mean and standard deviation values. *, \(p\) \(\leq\) 0.05; **, \(p\) \(\leq\) 0.01; ***, \(p\) \(\leq\) 0.001.  
with the support structure, but the magnitude of the increase was relatively small. The error ranges in the no-support, and support groups were 58.3-83.6 \(\upmu\)m and 58.9-72.9 \(\upmu\)m, respectively. The accuracy differed significantly between the presence and absence of the support structure for all postcuring times, but not in the control group that did not undergo postcuring (Figure 5A). The pattern was the same in the mandible-base group printed using standard gray resin, but the accuracy was lower than in the maxillary group, with error ranges of 130.4-185.6 \(\upmu\)m in the no-support group and 124.8-148.0 \(\upmu\)m in the support group (Figure 5B).