Orthodontics. Part 9: anchorage control and distal movement.

Anchorage is an important consideration when planning orthodontic tooth movement. Unwanted tooth movement known as loss of anchorage can have a detrimental effect on the treatment outcome. Anchorage can be sourced from the teeth, the oral mucosa and underlying bone, implants and extra orally. If extra-oral anchorage is used, particularly with a facebow then the use of at least two safety devices is mandatory.