# Long-Term CBCT Evaluation of Mandibular Third Molar Changes after Distalization in Adolescents
## 4 Discussion
\begin{table}
\begin{tabular}{l c c c c c c c c c} \hline \hline \multicolumn{1}{c}{\multirow{2}{*}{**Variables**}} & \multicolumn{2}{c}{**T1-T2**} & \multicolumn{2}{c}{**T2-T3**} & \multicolumn{2}{c}{**T1-T3**} & \multicolumn{2}{c}{**Post Hoc Analysis Bonferroni**} \\ \cline{2-10}  & **Mean** & **SD** & **Mean** & **SD** & **Mean** & **SD** & **P1** & **P2** & **P3** \\ \hline
8 angulation & \(-2.97\) & 6.78 & \(-2.40\) & 16.17 & \(-5.38\) & 15.23 & 0.084 & 1.000 & 0.218 \\
6 rotation & \(1.01\) & 17.39 & \(-1.96\) & 16.26 & \(-0.95\) & 10.90 & 1.000 & 1.000 & 1.000 \\
7 rotation & \(-5.18\) & 23.56 & 1.01 & 24.39 & \(-4.17\) & 26.91 & 0.763 & 1.000 & 1.000 \\
8 rotation & \(-2.86\) & 13.78 & 4.43 & 20.94 & 1.57 & 23.74 & 0.847 & 0.819 & 1.000 \\
6 MB cusp to frontal (mm) & \(-2.26\) & 2.43 & 1.14 & 3.51 & \(-1.12\) & 3.03 & 0.012 & 0.737 & 0.571 \\
6 MB cusp to horizontal (mm) & \(-1.25\) & 1.83 & \(-1.42\) & 2.03 & \(-2.67\) & 2.04 & 0.004 & 0.003 & \textless{}0.0001 \\
6 MB cusp to midsagittal (mm) & \(0.72\) & 2.69 & \(-0.76\) & 3.35 & \(-0.03\) & 3.66 & 0.498 & 0.724 & 1.000 \\
7 MB cusp to frontal (mm) & \(-1.72\) & 2.1 & 1.26 & 3.96 & \(-0.46\) & 3.32 & 0.027 & 0.761 & 1 \\
7 MB cusp to horizontal (mm) & \(-0.63\) & 2.78 & \(-2.02\) & 2.99 & \(-2.65\) & 2.41 & 0.720 & 0.004 & \textless{}0.0001 \\
7 MB cusp to midsagittal (mm) & 0.64 & 4.42 & \(-0.66\) & 5.43 & \(-0.02\) & 4.93 & 1.000 & 1.000 & 1.000 \\
8 MB cusp to frontal (mm) & 0.16 & 1.1 & 1.27 & 1.64 & 1.43 & 1.88 & 1 & 0.038 & 0.042 \\
8 MB cusp to horizontal (mm) & \(-0.52\) & 1.66 & \(-2.16\) & 2.89 & \(-2.69\) & 3.15 & 0.321 & 0.001 & \textless{}0.0001 \\
8 MB cusp to midsagittal (mm) & \(-0.03\) & 1.95 & 1.67 & 3.89 & 1.64 & 4.18 & 1.000 & 0.095 & 0.143 \\ Mandibular intercanine width & \(-0.10\) & 3.35 & 0.34 & 2.22 & 0.24 & 2.13 & 1.000 & 1.000 & 1.000 \\ Mandibular internormal width & 1.43 & 4.79 & \(-1.52\) & 6.32 & \(-0.09\) & 6.78 & 0.851 & 1.000 & 1.000 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: _Cont._After post-distalization, the samples in this study consisted of adolescents aged \(14.4\pm 1.3\) with cervical vertebral maturation stages (CVMSs) of CS3 and CS4 (Table 1). [PERSON] et al. [21] found that the peak increase in mandibular length occurs during this stage. Another report showed that continued accelerated craniofacial growth can be anticipated in the CS4 stage [22]. Interestingly, the treated group and the control group had the same CVMSs, of CS5 and CS6, post-retention, as seen in Table 1.  
Orthodontic appliances that produce posterior movement of the mandibular dentin, either through the tipping of individual teeth or through the translation of the dentition, may restrict the space for second and third molars, which can cause impaction of third molars [23; 24; 25; 26]. It is known that the third molars to show mesioangular and unfavorable positions in the long-term. [PERSON] et al. [12] evaluated the treatment outcomes of maxillary third molars during distalization by modified pendulum. The tooth buds of the third molars acted as a fulcra, causing the second molars to tip approximately \(8^{\circ}\) to the palatal plane after 2.6-mm distalization. In addition, [PERSON] et al. [27] demonstrated this effect by using the three-dimensional finite element method. The presence or absence of third-molar follicles did not significantly affect the movement of the first molars in their study. Several studies reported that premolar extraction treatment might produce posterior space and reduce the potential of third-molar impaction [28; 29]. Regarding the vertical and horizontal positions in our case, the lower third molars in the treatment group showed a more downward and mesial position compared to those in the control group. Accordingly, the potential for third-molar impaction could be high. On the other hand, [PERSON] et al. [16] reported that third molars moved distally and downward or distally and upward after maxillary molar distalization.