A patient presents with a cervical smooth surface lesion on the tooth with a concave, dish-shaped defect. What is the MOST likely cause?

Abfraction refers to cervical tooth loss caused by eccentric occlusal stress that flexes the tooth at the cervical fulcrum point, fatiguing and fracturing enamel and dentin crystals. The lesion is typically wedge-shaped or dish-shaped at the CEJ on the facial or buccal surface. Key: smooth surface + cervical location + stress association = abfraction. Abrasion from toothbrush may also cause cervical lesions but is typically from lateral pressure with abrasive toothpaste.