Table 4.
Measurements of the upper left premolars
| n | % | Minimum | Maximum | Mean | SD | M | ||
|---|---|---|---|---|---|---|---|---|
| Presence of concavity | Absent | 0 | 0 | |||||
| Present | 100 | 100 | ||||||
| Origin of the concavity | Cervical third of the crown | 34 | 34 | |||||
| Cervical third of the root | 57 | 57 | ||||||
| Middle third of the root | 5 | 5 | ||||||
| Apical third of the root | 0 | 0 | ||||||
| Middle third of the crown | 4 | 4 | ||||||
| Depth of the concavity (mm) | 0.2 | 2.01 | 0.94 | 0.38 | 0.95 | |||
| Buccolingual length (mm) | 1.71 | 6.4 | 4.37 | 0.91 | 4.35 | |||
| Distance from CEJ on the crown (mm) | 0 | 3.9 | 0.57 | 0.89 | 0 | |||
| Distance from CEJ on the root (mm) | 2.21 | 11.6 | 7.25 | 2.02 | 7.44 | |||
| Apicocoronal length (mm) | 2.21 | 14.69 | 7.82 | 2.25 | 8 | |||
| Amount of bone loss (BL) (CBCT) | 0 | 44 | 44 | |||||
| < 25% | 27 | 27 | ||||||
| 25–50% | 20 | 20 | ||||||
| > 50% | 9 | 9 | ||||||
| Amount of bone loss (BL) (Panoramic radiograph) | 0 | 49 | 49 | |||||
| < 25% | 23 | 23 | ||||||
| 25–50% | 21 | 21 | ||||||
| > 50% | 7 | 7 | ||||||
| Location of furcation | 0 | 52 | 52 | |||||
| Cervical Third | 1 | 1 | ||||||
| Middle Third | 22 | 22 | ||||||
| Apical Third | 25 | 25 | ||||||
| Number of roots | Single Root | 52 | 52 | |||||
| Double Root | 48 | 48 | ||||||
| Buccal root length (mm) | 8.41 | 16.8 | 13.6 | 1.69 | 13.61 | |||
| Palatinal root length (mm) | 9.07 | 15.88 | 12.85 | 1.78 | 12.91 | |||
| Buccopalatinally cervical root width (mm) | 6.4 | 9.7 | 8.29 | 0.7 | 8.4 | |||
n, number; SD, standard deviation; M, median