Co-axial computed tomography for optimizing orthodontic miniscrew implant size and site of placement

Absolute anchorage has been a critical aspect in orthodontics. Quantity and quality is a critical factor MSI placement. The present study was designed using a spiral computed tomography to assess the bone availability and clinically assess the optimized position and site for MSI placement in the posterior region.

Spiral computed tomography images often patients were obtained with requirement of MSI placement. Mesiodistal inter-radicular distance in the posterior region of the maxilla over narrowest inter-radicular space was measured at 2, 4, 6 and 8 mm from cementoenamel junction.

In the maxilla, the greatest inter-root distance was observed between the first molar and the second premolar at the 8-mm level from the CEJ. The inter-root distances at 4, 6, and 8 mm were significantly larger than the distance at 2 mm, showing a gradual increment as the level approaches the root apex.

The optimal site for placement of a frequently used MSI (diameter 1.8 to 2.0 mm) in between 2nd premolar--1st molar could be 4 mm from the CEJ and between 1st molar--2nd molar be 6 mm from the CEJ.