Evaluation of optimal parameters for the insertion of mini-implants at the mandibular ramus region based on cone-beam computed tomography.

OBJECTIVE

To determine the optimal parameters for mini-implant placement in the mandibular ramus.

MATERIAL AND

METHODS

Measurements were conducted on CBCT data from 50 subjects, covering five planes (OP2, OP4, OP6, OP8 and OP10), each with six sites (Site0, Site2, Site4, Site6, Site8 and Site10), and each site with five insertion angles (30°, 60°, 90°, 120°, and 150°). The data included measurements of bone depth, cortical bone thickness, canal distance, and the probability of molar interference.

RESULTS

The bone volume of the mandibular ramus is sufficient for placing orthodontic mini-implants. When mini-implants were implanted at appropriate heights, sites, and angles, contact with the mandibular nerve canal and interference with maxillary molars can be avoided.

CONCLUSIONS

Suitable insertion height was 4-8mm above the occlusal plane. Suitable insertion site was 4-8mm medial to the external oblique ridge. Suitable insertion angle was 120-150 degrees with the anterior surface of the mandibular ramus platform.