Molar Relationship
The antero-posterior relationship of the upper and lower first permanent molars, classified as Class I, II, or III according to Angle's classification.
Full Definition
The molar relationship describes how the upper and lower first permanent molars interdigitate in the sagittal (front-to-back) plane and is the cornerstone of Angle's classification system. In a Class I molar relationship, the mesiobuccal cusp of the upper first molar occludes in the buccal groove of the lower first molar. Class II indicates the lower molar is positioned distally, and Class III indicates a mesial position of the lower molar relative to normal. Editors must ensure that 'Class' is capitalised and followed by the Roman numeral when referring to Angle's classification. The term is distinct from 'incisor relationship', which describes the front teeth.
Usage
Usage note: Always capitalise 'Class' and use Roman numerals (I, II, III). Specify left and right sides where applicable.
In Context
- "The molar relationship was Class II division 1 on the right and Class I on the left." — Orthodontic assessment letter
- "Treatment aim: to achieve a Class I molar relationship bilaterally." — Treatment plan