## 4 Discussion
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Skull No.**} & **Number of the Created** & \multicolumn{2}{c}{**Distance between the Surface Point Created on the**} \\  & **Surface Points on the** & **Inner Surface of the Template and Its Projected** \\  & **Inner Surface of the** & \multicolumn{2}{c}{**Point on the Underlying Bone (mm)**} \\ \cline{3-4}  & **Template** & **Mean \(\pm\) SD** & **Maximum** \\ \hline
1 & 188 & 0.73 \(\pm\) 0.22 & 1.11 \\
2 & 179 & 0.86 \(\pm\) 0.27 & 1.57 \\
3 & 184 & 1.01 \(\pm\) 0.53 & 2.38 \\
4 & 178 & 0.82 \(\pm\) 0.45 & 1.83 \\
5 & 146 & 0.17 \(\pm\) 0.10 & 0.52 \\
6 & 149 & 0.79 \(\pm\) 0.30 & 1.33 \\
7 & 201 & 0.51 \(\pm\) 0.28 & 1.18 \\
8 & 163 & 0.94 \(\pm\) 0.40 & 2.26 \\
9 & 188 & 0.74 \(\pm\) 0.35 & 1.74 \\
10 & 272 & 0.89 \(\pm\) 0.27 & 1.65 \\ \hline \hline \end{tabular} SD: standard deviation.  
\end{table} 
Table 3: Fitness of the surgical template for each one of the 10 dry skulls. 1.0 mm) for maxillary surgery and 0.61 \(\pm\) 0.69 mm (75.3% of values within 1.0 mm) for mandibular surgery. In a case series of 32 maxillary osteotomy patients reported by [PERSON] et al. [3], fitting of the custom-made osteosynthesis plate was excellent in 23 patients (71.9%), good in 4 patients (12.5%), acceptable in 4 patients (12.5%), and not usable in 1 patient (3.1%). In contrast to encouraging results of CAD/CAM-based template, clinically significant surgical errors (>2.0 mm) have also been reported. In the study by [PERSON] et al. [20], the accuracy showed a reproducibility of <2 mm in 7 out of 10 patients. However, three other cases exhibited maximum errors of 2.4, 3.2, and 6.0 mm. [PERSON] et al. [27] also reported the maximum error of 2.02 mm after bimaxillary surgery using CAD/CAM-generated cutting guides and patient-specific implants. Regarding the cause of the surgical error in the template-based surgery, [PERSON] et al. [29] suggested that the surgical error was attributed the contact surface between the template and the underlying bone, and that a wider or longer surgical template ensures a higher positioning accuracy. In our study, we assessed the positioning accuracy of surface-based CAD/CAM templates, where the placement of the templates in the same position as the surgical simulation is essential to perform subsequent surgical procedures precisely. To maximize the positioning accuracy, the CAD/CAM template used in this study was designed to cover the zygomaticomaxillary buttress and piriform aperture. Furthermore, the right and left parts of the template were joined at the midline with wedge-form interlocking structures. Though there were statistically significant differences between the planned and actual positions of the template, mean absolute deviations (0.41 mm in medio-lateral direction, 0.55 mm in antero-posterior direction, and 0.69 mm in antero-posterior direction) and RMSD (1.07 mm) were clinically acceptable. The template exhibited more accurate positioning in the medio-lateral direction, followed by the antero-posterior and the supero-inferior directions. With respect to the fitness of the template, the gap between the inner surface of the surgical template and the underlying bone was also clinically acceptable (0.75 mm on average). These results suggest that surface-based CAD/CAM templates may be repositioned precisely without the help of occlusal splints. There might be other consideration factors for the maxillary templates. First, it is necessary to consider the accuracy of the 3D printed template compared to the design of the template, and the possibility of deformation from 3D printing to actual use in surgery. In addition, when the template is fixed to the bone surface with screws, it is necessary to consider the technical aspects, as the excessive pressing force may reduce the intimate contact of other parts and increase the error occurrence. Another important consideration is the anatomical features of the site where the template will be located.