Wear of opposing tooth surfaces resulting from tooth‑to‑tooth contact during normal function or parafunction (mastication, bruxism), producing matching facets, flattening or loss of occlusal morphology attributable primarily to direct occlusal contact.

Principle

Repeated occlusal contact transmits localized contact stresses that abrade and flatten opposing enamel surfaces; the pattern and rate of attrition depend on occlusal scheme, contact force, movement direction and presence of protective factors like saliva.

Demonstration

Illustrative scenario: A patient with nocturnal clenching reports tooth wear (situation). Examination reveals polished, matching wear facets on opposing molars consistent with bruxism (recognition). Management includes occlusal assessment, night guard provision and, where indicated, occlusal rehabilitation (action). Wear progression may slow with reduced parafunctional activity, but lost occlusal anatomy often requires restorative reconstruction to regain function (consequence).

Misapplication

Attributing flattened occlusal surfaces to erosion or abrasion without considering occlusal contact; the error is ignoring matching facets and occlusal history, which leads to inappropriate prevention focusing on brushing or dietary acids rather than occlusal management.

Consequence

Continued attrition can alter occlusal vertical dimension, impair mastication, expose dentin and necessitate restorative rehabilitation; controlling parafunctional forces can reduce progression but cannot spontaneously recreate original occlusal anatomy once lost.

Reversal

If occlusal contacts are modified, parafunctional activity reduced or protective appliances used, attrition rate can be diminished; however, biological regrowth of worn enamel does not occur, so morphological restoration requires mechanical reconstruction.

Boundary

Clearly within: Complementary, polished wear facets on antagonistic cusps matching in size and shape. Boundary case: Mixed lesions where attrition coexists with erosion—discrimination relies on facet morphology and etiologic history. Clearly outside: Cervical wedge defects from abrasion/abfraction or chemically smoothed erosion lesions.

Semantic Tension

Management balances occlusal control (splints, behavior change, occlusal adjustment) against restorative reconstruction; excessive occlusal intervention risks iatrogenic harm while ignoring occlusion risks continued wear.

Synthesis

Attrition is contact‑driven interocclusal wear recognized by matching antagonist facets; effective care addresses the occlusal cause to limit progression and uses targeted restoration to replace lost form when needed.