# Evaluation of Tooth Movement Accuracy with the F22 Aligner System: A Retrospective Study
## 3 Results
Specifically, rotation was significantly more accurate at the mandibular incisors (=72.64 \(\pm\) 32.06%) than at the mandibular canines (57.70 \(\pm\) 28.90%, \(p\) < 0.001), mandibular premolars (54.19 \(\pm\) 35.39%, \(p\) < 0.001), maxillary canines (49.59 \(\pm\) 29.43%, \(p\) < 0.001) and maxillary incisors (61.28 \(\pm\) 28.28%, \(p\) < 0.001), but significantly less accurate at the maxillary canines (46.59 \(\pm\) 29.43%) than at the maxillary incisors (61.28 \(\pm\) 28.28%, \(p\) < 0.001) and maxillary premolars (62.86 \(\pm\) 35.03%, \(p\) < 0.001), and at the mandibular premolars (54.19 \(\pm\) 35.79%) than at both the maxillary premolars (62.86 \(\pm\) 35.03%, \(p\) = 0.044) and maxillary incisors (61.28 \(\pm\) 28.28%, \(p\) < 0.001) (Table 3). The analysis of the CHAID regression trees reveals that mean inclination accuracy is not influenced by any of the variables taken into consideration, i.e., amount of prescribed movement (T1), tooth type and presence or absence of grip points. As for the angulation, distal angulation in the T1 range \(-\)20.1\({}^{\circ}\) to \(-\)0.2\({}^{\circ}\)was more accurate (accuracy 67.9-76.3%, n = 422) than mesial angulation in the T1 range \(-\)0.2\({}^{\circ}\) to 19.6\({}^{\circ}\) (accuracy 59.4-67.9%, n = 297). Distal tipping accuracy was of between 51% and 59.4% at the mandibular premolars (n = 42), 59.4% and 67.9% at the maxillary incisors and mandibular canines (n = 179) and 84.8% and 93.2% at the maxillary and mandibular incisors (n = 201). Paradoxically, grip points seemed to lower the effectiveness of T1 between \(-\)0.2\({}^{\circ}\) and 19.6\({}^{\circ}\) (n = 52), as they yielded an accuracy value of between 42.5% and 51%, as compared to the range 59.4% to 67.9% when they were absent (n = 245) (Figure 5). As for rotation, both maxillary and mandibular canines and the mandibular premolars displayed an average accuracy of between 40.6% and 45.1% (n = 445), the mandibular incisors of between 58.4% and 62.8% (n = 307), and the maxillary incisors and premolars of between 49.5% and 53.9% (n = 472). Grip points increased the rotation accuracy at both the mandibular incisors and the maxillary incisors and premolars. Indeed, at the mandibular incisors, the presence of grip points raised the accuracy to between 80.6% and 85% (n = 15), as compared to the range 53.9% to 58.4% (n = 292) recorded for the group without grip \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multicolumn{1}{c}{\multirow{2}{*}{**Tooth Type/Arch**}} & \multicolumn{2}{c}{**Inclination**} & \multicolumn{2}{c}{**Angulation**} & \multicolumn{2}{c}{**Rotation**} \\ \cline{3-8}  & _p_-Value & **Significance** & _p_-Value & **Significance** & _p_-Value & **Significance** \\ \hline
**Incisor-Maxilla** & **Canine–Maxilla** & 1.000 & NS & 0.007 & * & \textless{}0.001 & * \\  & **Premolar–Maxilla** & 1.000 & NS & 0.421 & NS & 1.000 & NS \\  & **Incisor-Mandible** & 1.000 & NS & 0.931 & NS & 0.021 & * \\  & **Canine–Mandible** & 0.939 & NS & 0.995 & NS & 0.228 & NS \\  & **Premolar–Mandible** & 0.797 & NS & 0.006 & * & 0.001 & * \\
**Canine–Maxilla** & **Premolar–Maxilla** & 0.997 & NS & 1.000 & NS & 0.038 & * \\  & **Incisor–Mandible** & 0.997 & NS & 0.155 & NS & \textless{}0.001 & * \\  & **Canine–Mandible** & 0.706 & NS & 0.475 & NS & 0.609 & NS \\
**Premolar–Maxilla** & 0.602 & NS & 0.996 & NS & 1.000 & NS \\  & **Incisor–Mandible** & 1.000 & NS & 0.800 & NS & 0.212 & NS \\  & **Canine–Mandible** & 0.838 & NS & 0.920 & NS & 0.664 & NS \\  & **Premolar–Mandible** & 0.708 & NS & 1.000 & NS & 0.044 & * \\
**Incisor–Mandible** & **Canine–Mandible** & 0.801 & NS & 1.000 & NS & \textless{}0.001 & * \\  & **Premolar–Mandible** & 0.601 & NS & 0.083 & NS & \textless{}0.001 & * \\
**Canine–Mandible** & **Premolar–Mandible** & 1.000 & NS & 0.204 & NS & 0.789 & NS \\ \hline \hline \end{tabular}  
* NS: not significant.  
\end{table} 
Table 3: Statistical comparison of accuracy [\(\,\)T2/T1\(\,\)1] \(\times\) 100 of each movement investigated by tooth type for both maxilla and mandible (_p_ < 0.05 *).