Winter's Lines
A radiographic assessment method using three intersecting lines drawn on a panoramic image to predict the difficulty of mandibular third molar extraction.
Full Definition
Winter's lines comprise three reference lines — the white line (along the occlusal plane of the molars), the amber line (along the bone surface at the ramus), and the red line (a perpendicular from the white line to the point of application of the elevator) — used to estimate the depth and angulation of an impacted lower wisdom tooth. The method provides a quick visual guide to surgical complexity and is frequently referenced in pre-operative assessment notes and teaching materials. In editing, the term is capitalised because it is an eponym derived from the surname of the originating clinician. Authors sometimes incorrectly write it as 'Winter lines' (without the possessive) or in lowercase; editors should correct both.
Usage
Usage note: Capitalise as an eponym: 'Winter's Lines'. The possessive apostrophe is required. Do not conflate with the Pell and Gregory classification, which assesses different radiographic parameters.
In Context
- "Winter's Lines were applied to the preoperative panoramic radiograph to grade the anticipated difficulty of the procedure." — Pre-operative assessment note
- "The author incorrectly wrote 'winters lines'; the editor restored the capitalisation and apostrophe." — Journal manuscript editing