Table 2.
Factors associated with ectopic eruption (EE) of the maxillary first permanent molars (FPM) in cephalometric radiograph analysis.
| Measurement | NEG | EEG | P value |
|---|---|---|---|
| S–Ar (mm) | 30.03 ± 3.20 (30.05) | 29.65 ± 3.00 (29.70) | 0.415 |
| Go-Me (mm) | 56.19 ± 4.06 (56.10) | 55.12 ± 4.01 (55.55) | 0.098 |
| FMA (°) | 27.81 ± 5.43 (27.35) | 26.61 ± 5.96 (27.25) | 0.291 |
| FMIA (°) | 59.20 ± 7.88 (59.05) | 62.19 ± 7.58 (62.25) | 0.008∗∗ |
| IMPA (°) | 92.98 ± 7.89 (93.35) | 91.19 ± 6.60 (91.70) | 0.140 |
| SNA (°) | 80.68 ± 3.56 (80.25) | 78.83 ± 3.75 (78.45) | 0.001∗∗ |
| SNB (°) | 76.38 ± 3.75 (75.85) | 76.81 ± 4.26 (76.80) | 0.417 |
| ANB (°) | 4.30 ± 3.35 (4.60) | 2.02 ± 3.30 (1.75) | <0.001∗∗∗ |
| Wits (mm) | −1.02 ± 4.68 (−1.35) | −4.16 ± 4.77 (−4.40) | <0.001∗∗∗ |
| Ptm-S (mm) | 16.96 ± 2.16 (16.95) | 17.66 ± 2.50 (17.60) | 0.068 |
| U6-PTV (mm) | 8.23 ± 2.42 (8.15) | 8.45 ± 2.78 (8.30) | 0.474 |
| UV-PTV (mm) | 17.87 ± 2.84 | 17.22 ± 3.15 | 0.105 |
| Ptm-A (mm) | 42.78 ± 3.06 (42.35) | 41.00 ± 3.18 (40.65) | <0.001∗∗∗ |
| ANS-PNS (mm) | 49.28 ± 3.71 (49.05) | 47.18 ± 3.43 (47.00) | <0.001∗∗∗ |
| Overjet (mm) | 3.62 ± 3.39 (4.55) | 0.54 ± 3.74 (−0.30) | <0.001∗∗∗ |
| Overbite (mm) | 2.41 ± 2.00 (2.00) | 1.51 ± 2.00 (1.60) | 0.002∗∗ |
S–Ar, the vertical distance between the point sella (S) and the point articulare (Ar); Go-Me, the distance between the point gonion (Go) and the point menton (Me); SNA, the angle formed by the point S, the point nasion (N) and the point subspinable (A); SNB, the angle formed by the point S, the point N and the point supramental (B); ANB, the angle formed by the point A, the point N and the point B; Wits, the distance between the perpendicular projections from the point A and point B onto the occlusal plane (OP); Ptm-S, the distance between the perpendicular projections from the point pterygomaxillary fissure (Ptm) and point S onto the Frankfort horizontal (FH) plane; U6-PTV, the distance between the perpendicular projections from the point Ptm and the distal point of the maxillary first molar onto the FH plane; UV-PTV, the distance between the perpendicular projections from the point Ptm and the distal point of the maxillary second primary molar onto the FH plane; Ptm-A, the distance between the perpendicular projections from the point Ptm and the point A onto the FH plane; ANS-PNS, the distance between the point anterior nasal spine (ANS) and the point posterior nasal spine (PNS); Overjet, the anteroposterior distance between the most labial surface of the upper incisor and the most labial surface of the lower incisor when the teeth are in maximum intercuspal position; Overbite, the vertical overlap of the upper and lower incisors when the teeth are in maximum intercuspal position.
∗∗P < 0.01; ∗∗∗P < 0.001.