Hard and soft tissue considerations at mini-implant insertion sites

A selection of abstracts of clinically relevant papers from other journals. The abstracts on this page have been chosen and edited by John R. Radford.

Abstract

Although the mandibular retromolar region has both anatomical and soft tissue variation, this site for placement of mini-implants is ideal for enabling the uprighting of mandibular molar teeth and full arch retraction.

Main

Baumgaertel S. J Orthod 2014; 41 (Suppl 1): s3–7

There is a balance; the mini-implant must simplify tooth movement, yet this has to be weighed against possible traumatic damage to underlying structures. In order to secure primary stability of mini-implants, it is held that thick cortical bone is preferable to thin cortical bone. Placing mini-implants using too low an insertion torque results in poor primary stability, but if the torque is too high there is osteonecrosis of the bone. The placement of mini-implants in the palate is ideal. Mini-implants can be placed between molar teeth, with their single palatal roots, and molar and premolar teeth. In addition, when mini-implants are situated in the palate, they are bounded by attached gingiva. The reason for the sub-optimal outcome when mini-implants are placed through alveolar mucosa maybe more a consequence of tissue mobility and the variable thickness of the underlying cortical bone, than the alveolar mucosa per se.