abfraction
noun
ab·frac·tion
| \ ab-ˈfrak-shən
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Medical Definition of abfraction
: a mechanism that is postulated to explain loss of tooth enamel and dentin in the part of a tooth between the crown and root in the absence of tooth decay
also
: the narrow usually V-shaped area of tooth loss caused by abfraction
Note: Abfraction is postulated to occur when the force generated by occlusion (as during chewing) causes stress to concentrate on certain points of a tooth. This stress results in tooth flexure and leads to the eventual breaking away of hard tissue.