Torque
In orthodontics, the labiolingual or buccolingual inclination of a tooth crown or root relative to a reference plane, applied through a couple of forces in the bracket or archwire.
Full Definition
Torque in orthodontic terminology refers to the third-order movement that controls the labiolingual (for anterior teeth) or buccolingual (for posterior teeth) angulation of tooth roots relative to their crowns. Positive torque tips the crown labially and the root palatally/lingually; negative torque does the opposite. It is encoded into pre-adjusted appliance brackets and can be augmented by archwire bends. Editors must be aware that 'torque' is used as both a noun and a verb in orthodontic literature ('to torque a tooth'), and that it is distinct from tipping and rotation. Misuse of 'torque' to mean simple rotation is a frequent editorial error.
Usage
Usage note: Do not conflate with 'rotation' (movement around the long axis) or 'tipping' (first-order and second-order crown movement). Acceptable as a verb ('to torque') in clinical records but should be phrased more precisely in formal publications.
In Context
- "Palatal root torque was added to the upper incisor brackets to improve axial inclination." — Orthodontic treatment progress note
- "The author uses 'torque' and 'rotation' interchangeably; these should be distinguished in revision." — Manuscript peer-review comment