Abfraction

Part of speech: noun

Definitions

1. The term describes the loss of tooth substance due to mechanical stress, leading to characteristic defects that appear as notches or wedges in the dental structure
2. It refers to tooth hard tissue loss that occurs as a result of excessive occlusal forces, manifesting as localized enamel and dentin erosion
3. The term denotes the localized loss of dental tissue caused by factors like occlusal stress, leading to visible notches in the tooth structure

Etymology: Abfraction is a dental term coined in 1991 by joining the prefix "ab-", meaning "away from," to "fraction," an English word for a breaking or a broken piece. The prefix is the familiar Latin one seen in "abnormal" and "abduct," so the term literally names a breaking away. The wedge-shaped notches it describes usually form near the gum line, where the enamel is thinnest. Repeated flexing of a tooth under heavy biting forces, rather than brushing or decay, is thought to stress the enamel until it fractures and peels away. The name fits that picture closely: the tooth substance is pulled apart and lost at the edge where the crown meets the root.