PDF: The optimal position for insertion of Orthodontic Miniscrews

Miniscrews feature several advantages over other devices used to achieve anchorage; however, using computed tomography (CT) scans to determine the appropriate areas to place these devices for all patients can be expensive.

The search for orthodontic treatment methods requiring minimal patient compliance while simultaneously providing maximal anchorage has led professionals to use a wide array of devices, such as mini-plates, dental implants and miniscrews.

Miniscrews offer advantages such as their small size, low cost, streamlined insertion and removal surgical procedures and immediate load while providing adequate anchorage to enable orthodontic movements.

Determining what type of orthodontic movement will be used prior to miniscrew placement is of paramount importance because insertion at an unsuitable site is likely to restrain the desired movement.

Miniscrews are approximately 1.2 to 1.5 mm in diameter and are not completely stable. Rather, they tend to drift by an average of less than 0.5 mm.

It is therefore advisable to allow a 2 mm space (1 mm on each side) between the miniscrews and adjacent anatomical structures.

This study sought to assess mesiodistal interradicular distances at heights of 2, 5, 8 and 11 mm measured from the alveolar bone crest, using measurements obtained from CT images along with data from other studies to determine the most favorable sites for miniscrew placement.