Table 3. Regression models using physiological ratios for predicting chronological ages.
| Plan | Tooth | Gender | Linear Regression Equation | SEE | R2 |
|---|---|---|---|---|---|
| Axial | Upper Central | M | Y=66-543X | 7.21 | 0.551 |
| F | Y=64.7-524X | 7.68 | 0.504 | ||
| Upper Canine | M | Y=67.3-591X | 7.98 | 0.429 | |
| F | Y=61.2-454X | 9.05 | 0.306 | ||
| Lower Central | M | Y=65.4-734X | 7.74 | 0.498 | |
| F | Y=61.8-657X | 7.40 | 0.488 | ||
| Lower Canine | M | Y=71.5-789X | 7.83 | 0.583 | |
| F | Y=61-535X | 8.53 | 0.412 | ||
| Sagittal | Upper Central | M | Y=69-264X | 8.43 | 0.388 |
| F | Y=73.6-309X | 7.10 | 0.576 | ||
| Upper Canine | M | Y=66.9-169X | 9.47 | 0.195 | |
| F | Y=63-160X | 9.53 | 0.229 | ||
| Lower Central | M | Y=63.7-171X | 9.24 | 0.284 | |
| F | Y=62.5-184X | 8.08 | 0.391 | ||
| Lower Canine | M | Y=75.3-216X | 9.47 | 0.389 | |
| F | Y=56.9-127X | 10.5 | 0.109 |
SEE: Standard error of estimate, R2: Coefficient of determination, M: Male, F: Female, Y:predicted age, X: PTR.