Table 3.
Descriptive statistics
| Non-extraction | Extraction | p valuea | ||
|---|---|---|---|---|
| Cephalometric variables | ||||
| SNA | Mean | 81.76 | 81.26 | 0.184 |
| SD | 3.93 | 3.79 | ||
| SNB | Mean | 78.54 | 77.11 | 0.000 |
| SD | 3.65 | 3.54 | ||
| ANB | Mean | 3.16 | 4.08 | 0.000 |
| SD | 2.27 | 2.21 | ||
| U1-SN | Mean | 104.12 | 103.23 | 0.215 |
| SD | 7.26 | 7.71 | ||
| U1-NA (1) | Mean | 22.15 | 21.72 | 0.535 |
| SD | 7.00 | 7.62 | ||
| NSGn | Mean | 67.13 | 68.88 | 0.000 |
| SD | 4.09 | 3.71 | ||
| FMIA | Mean | 61.95 | 60.32 | 0.022 |
| SD | 7.55 | 6.71 | ||
| IMPA | Mean | 92.38 | 92.58 | 0.763 |
| SD | 5.99 | 5.51 | ||
| FMA | Mean | 25.60 | 27.05 | 0.011 |
| SD | 397 | 145 | ||
| L1-NB (1) | Mean | 24.99 | 25.72 | 0.258 |
| SD | 6.59 | 6.66 | ||
| U1-L1 | Mean | 129.48 | 128.30 | 0.257 |
| SD | 10.51 | 11.26 | ||
| SN-PP | Mean | 7.09 | 7.25 | 0.631 |
| SD | 3.52 | 3.11 | ||
| SN-OP | Mean | 16.27 | 17.72 | 0.001 |
| SD | 4.58 | 4.63 | ||
| Z angle | Mean | 75.05 | 71.79 | 0.000 |
| SD | 7.04 | 6.39 | ||
| PNS-A | Mean | 48.97 | 49.01 | 0.939 |
| SD | 4.48 | 5.26 | ||
| U1-NA (2) | Mean | 3.97 | 4.18 | 0.479 |
| SD | 2.56 | 3.12 | ||
| L1-NB (2) | Mean | 4.34 | 5.18 | 0.000 |
| SD | 2.39 | 2.59 | ||
| L1-A Pg | Mean | 1.92 | 2.38 | 0.056 |
| SD | 2.44 | 2.63 | ||
| Pg-NB | Mean | 1.43 | 0.94 | 0.007 |
| SD | 1.89 | 1.66 | ||
| WITS | Mean | -0.15 | 0.58 | 0.023 |
| SD | 2.82 | 3.41 | ||
| N-Me | Mean | 114.67 | 116.74 | 0.073 |
| SD | 10.15 | 12.41 | ||
| N-ANS | Mean | 51.03 | 51.48 | 0.380 |
| SD | 5.12 | 5.74 | ||
| ANS-Me | Mean | 65.84 | 67.46 | 0.030 |
| SD | 6.39 | 8.03 | ||
| LL-E-plane | Mean | -1.72 | -0.22 | 0.000 |
| SD | 3.12 | 2.90 | ||
| S-Go | Mean | 72.93 | 72.31 | 0.449 |
| SD | 8.08 | 9.54 | ||
| S-Ar | Mean | 33.98 | 33.54 | 0.297 |
| SD | 4.36 | 4.41 | ||
| Model variables | ||||
| Overbite | Mean | 3.14 | 3.53 | 0.033 |
| SD | 1.93 | 1.71 | ||
| Overjet | Mean | 2.85 | 3.45 | 0.004 |
| SD | 1.94 | 2.21 | ||
| Upper crowding | Mean | -1.16 | -5.00 | 0.000 |
| SD | 3.79 | 3.79 | ||
| Lower crowding | Mean | -1.98 | -6.63 | 0.000 |
| SD | 3.17 | 3.60 | ||
| Upper midline deviation | Mean | 0.06 | 0.32 | 0.034 |
| SD | 1.00 | 1.32 | ||
| Lower midline | Mean | 0.00 | -0.09 | 0.573 |
| SD | 1.19 | 1.60 | ||
| Demographic variables | ||||
| Age | Mean | 14.55 | 14.52 | 0.948 |
| SD | 5.36 | 4.86 | ||
a t test for independent samples.