Number and ratio of screw holes located in each zone according to the position at each arch (left and right)
| Left | Right | |
|---|---|---|
| Zone A | 132 | 98 |
| Zone B | 40 | 52 |
| Zone C | 35 | 35 |
| Total | 207 | 185 |
| Ratio of zone A | 0.638 | 0.530 |
| Ratio of zone B | 0.193 | 0.281 |
| Ratio of zone C | 0.169 | 0.189 |