Table 3. Distance to the IAN and available bone thickness measurements.
| Parameter | Mean ± SD | Minimum value | Maximum value |
|---|---|---|---|
| RF-I | 15.68 ± 2.13 | 9.8 | 21.7 |
| MRA-I | 7.06 ± 2.22 | 2.2 | 14.3 |
| DRA-I | 6.48 ± 2.30 | 1.4 | 12.9 |
| IRB2 | 2.81 ± 0.50 | 1.6 | 4.0 |
| IRB4 | 3.30 ± 0.62 | 2.1 | 5.1 |
| IRBA | 4.44 ± 1.02 | 1.9 | 7.5 |
RF-I: root furcation fornix to inferior alveolar nerve distance; MRA-I/DRA-I: mesial/distal root apex to the inferior alveolar nerve distance; IRB2/IRB4: the interradicular alveolar bone thickness at 2 mm, 4 mm apical from the furcation fornix; IRBA: the interradicular alveolar bone thickness between the mesial and distal root apex.