## 3 Results
\begin{table}
\begin{tabular}{l c c c c c c c c} \hline \hline
**Variables** & \multicolumn{2}{c}{**CAG**} & \multicolumn{2}{c}{**RG**} & & & & \\ \multicolumn{2}{c}{(_n_ = 15; 8 F; 7 M)} & \multicolumn{2}{c}{(_n_ = 17; 9 F; 8 M)} & & & & \\ \hline
**Linear Measurements (mm)** & **Mean** & **SD** & **Mean** & **SD** & **Diff** & **SD** & **95\% CI** & \(p\) **Value** \\ \hline Inter-canine width (III-III) & 3.3 & 1.5 & 1.8 & 1.1 & 1.5 & 0.5 & 0.558 to 2.442 & **\(\ast\ast\)** \\ \hline First inter-deciduous molar width (IV-IV) & 3.9 & 1.2 & 2.5 & 1.3 & 1.4 & 0.4 & 0.493 to 2.307 & **\(\ast\ast\)** \\ \hline Second inter-deciduous molar width (V-V) & 4.1 & 1.3 & 3.6 & 1.2 & 0.5 & 0.4 & \(-\)0.403 to 1.403 & NS \\ \hline First inter-molar mesial width (6-6 mesial cusps) & 3.3 & 0.7 & 3.6 & 1.7 & -0.3 & 0.5 & \(-\)1.263 to 0.663 & NS \\ \hline First inter-molar distal width (6-6 distal cusps) & 2.1 & 0.8 & 3.3 & 1.2 & \(-\)1.2 & 0.4 & \(-\)1.947 to \(-\)0.453 & **\(\ast\ast\)** \\ \hline Inter-canine transpalatal width (III-III) & 3.3 & 0.9 & 1.8 & 1.3 & 1.5 & 0.4 & 0.682 to 2.318 & *** \\ \hline First inter-deciduous molar & 4.0 & 0.9 & 2.6 & 1.2 & 1.4 & 0.4 & 0.626 to 2.174 & *** \\ \hline Second inter-deciduous molar & 4.1 & 0.7 & 4.0 & 1.3 & 0.1 & 0.4 & \(-\)0.669 to 0.869 & NS \\ \hline First inter-molar transpalatal width (6-6 transpalatal) & 2.2 & 0.6 & 3.1 & 2.1 & \(-\)1 & 0.6 & \(-\)2.048 to 0.248 & NS \\ \hline \hline \end{tabular}  
* NS: not significant, **\(p<\) 0.01; *** \(p<\) 0.001; CI: confidence interval; SD: standard deviation.  
\end{table} 
Table 2: Descriptive and statistical comparison of T2-T1 changes for linear measurements between Clear aligners and RME groups. \begin{table}
\begin{tabular}{l c c c c c c c c} \hline \hline
**Variables** & \multicolumn{2}{c}{**CAG**} & \multicolumn{2}{c}{**RG**} & & & & \\ \multicolumn{2}{c}{(_n_ = 15; 8 F; 7 M)} & \multicolumn{2}{c}{(_n_ = 17; 9 F; 8 M)} & & & & \\ \hline
**Mean** & **SD** & **Mean** & **SD** & **Diff** & **SD** & **95\% CI** & \(p\) **Value** \\ \hline
**Angular measurements (\(\ast\))** & & & & & & & & \\ \hline Right deciduous canine crown & 19.6 & 4.4 & 21.4 & 2.4 & \(-\)1.8 & 1.2 & \(-\)4.317 to 0.717 & NS \\ \hline Left deciduous canine crown angulation (63) & 17.1 & 2.5 & 19.3 & 3.6 & \(-\)2.2 & 1.1 & \(-\)4.468 to 0.068 & NS \\ \hline Right first deciduous molar crown & 17.3 & 1.8 & 17.8 & 2.1 & \(-\)0.5 & 0.7 & \(-\)1.922 to 0.922 & NS \\ \hline Left first deciduous molar crown & 26.0 & 3.9 & 26.0 & 2.7 & 0 & 1.2 & \(-\)2.398 to 2.398 & NS \\ \hline Right second deciduous molar crown & 24.6 & 3.4 & 24.9 & 3.3 & \(-\)0.3 & 1.2 & \(-\)2.721 to 2.121 & NS \\ \hline Left second deciduous molar crown & 23.2 & 3.4 & 24 & 2.9 & \(-\)0.8 & 1.1 & \(-\)3.074 to 1.474 & NS \\ \hline Right first molar crown angulation (16) & 19.2 & 7.4 & 21 & 5 & \(-\)1.8 & 2.2 & \(-\)6.312 to 2.712 & NS \\ \hline Left first molar crown angulation (26) & 22.3 & 8.2 & 22.3 & 5.2 & 0 & 2.4 & \(-\)4.896 to 4.896 & NS \\ \hline \hline \end{tabular}  
* NS: not significant; CI: confidence interval; SD: standard deviation.  
\end{table} 
Table 1: _Cont._The comparison of T2-T1 changes for transversal linear measurements between RG and CAG groups showed statistically significant differences in the inter-canine width (+1.5 mm \(\pm\) 0.5 mm in CAG), in the first inter-deciduous molar width (+1.4 mm \(\pm\) 0.4 mm in CAG), in the first inter-molar distal width (+1.2 mm \(\pm\) 0.4 mm in RG), in the inter-canine transpalatal width (+1.5 mm \(\pm\) 0.5 mm in CAG), and in the first inter-deciduous molar transpalatal width (+1.4 mm \(\pm\) 0.4 mm in CAG). Moreover, the comparison of T2-T1 changes for angular measurements showed a statistically significant increase in the crown angulation for all the examined teeth in patients treated with aligners, except for the first molars.