Table 3 Dental arches dimensions changes over the time in the treatment time (T2-T1) and long-term follow-up time (T3-T2) (independent t tests)
Variables (mm) | Group mild crowding (N = 16) | Group severe crowding (N = 25) | P | Group mild crowding (N = 16) | Group severe crowding (N = 25) | P |
|---|---|---|---|---|---|---|
Mean (SD) | Mean (SD) | Mean (SD) | Mean (SD) | |||
Treatment changes T2-T1 | Long-term follow-up changes T3-T2 | |||||
Maxillary dental casts measurements | ||||||
Little irregularity index | − 6.48 (2.97) | − 8.29 (4.01) | 0.129 | 1.18 (2.18) | 2.59 (2.35) | 0.062 |
3–3 width | 0.56 (2.00) | 0.62 (2.18) | 0.934 | − 1.90 (3.73) | − 0.85 (1.53) | 0.214 |
5–5 width | − 1.39 (1.61) | − 0.96 (2.24) | 0.514 | − 1.50 (1.71) | − 1.16 (1.71) | 0.541 |
6–6 width | − 1.11 (2.02) | − 1.30 (2.05) | 0.770 | − 0.65 (1.80) | − 0.34 (1.40) | 0.560 |
Arch length | − 5.18 (4.33) | − 6.00 (3.13) | 0.484 | − 2.60 (3.59) | − 0.90 (2.44) | 0.078 |
Arch perimeter | − 8.75 (6.80) | − 9.21 (4.71) | 0.801 | − 3.05 (2.04) | − 2.49 (3.81) | 0.596 |
Mandibular dental casts measurements | ||||||
Little irregularity index | − 2.73 (2.18) | − 9.47 (2.49) | 0.000* | 3.08 (2.35) | 4.12 (2.75) | 0.222 |
3–3 width | 0.20 (1.79) | 1.42 (2.25) | 0.076 | -2.51 (2.72) | − 1.79 (2.01) | 0.339 |
5–5 width | − 4.04 (3.27) | − 1.66 (1.92) | 0.006* | -0.91 (2.11) | − 1.46 (2.05) | 0.420 |
6–6 width | − 3.27 (2.21) | − 2.55 (2.33) | 0.337 | 1.00 (2.25) | 0.22 (2.78) | 0.355 |
Arch length | − 5.25 (2.21) | − 4.49 (2.23) | 0.295 | -2.29 (1.55) | − 1.30 (2.32) | 0.141 |
Arch perimeter | − 9.45 (5.44) | − 10.16 (2.71) | 0.583 | -3.72 (2.53) | − 3.14 (2.66) | 0.495 |