Miniscrew implants: The Aarhus anchorage system

Abstract

The limitations of orthodontics, as determined by anchorage problems, have become more obvious as the number of adults seeking treatment increases. Different types of intraoral-extradental anchorage, such as infrazygomatic crest ligature wires, miniplates, and miniscrews, have been suggested to overcome the limitations of traditional orthodontic anchorage. In the present article, the development of a miniscrew anchorage system is outlined. Based on the results of monkey experiments and finite element analysis, the locations for miniscrew placement and loading protocols are discussed. These studies suggest that immediate loading with known forces increases the bone density surrounding the miniscrews. Treatment planning, indications for skeletal anchorage, miniscrew biomechanics, and possible complications with the Aarhus anchorage® system are discussed. The limitations of orthodontics, as determined by anchorage problems, have become more obvious as the number of adults seeking treatment increases. Different types of intraoral-extradental anchorage, such as infrazygomatic crest ligature wires, miniplates, and miniscrews, have been suggested to overcome the limitations of traditional orthodontic anchorage. In the present article, the development of a miniscrew anchorage system is outlined. Based on the results of monkey experiments and finite element analysis, the locations for miniscrew placement and loading protocols are discussed. These studies suggest that immediate loading with known forces increases the bone density surrounding the miniscrews. Treatment planning, indications for skeletal anchorage, miniscrew biomechanics, and possible complications with the Aarhus anchorage® system are discussed.