Pathology · single question
What is the KEY difference between ABFRACTION and ABRASION?
Show answer and explanation
Correct answer: C. Shape of the lesion
Abfraction and abrasion both affect the cervical area of teeth, but differ in lesion SHAPE: Abfraction: wedge-shaped/angular notch at the CEJ caused by eccentric occlusal forces creating stress concentration at the cervical area. Abrasion: dish-shaped/saucer-shaped or rounded groove caused by mechanical friction (toothbrush, abrasives). Both occur at the cervical area (similar location), so location is not the key differentiator. Shape is the defining clinical feature.
- A. CORRECT. The SHAPE differentiates them: abfraction = wedge-shaped/V-shaped angular notch; abrasion = saucer-shaped/rounded groove.
- B. Incorrect. Color is not a reliable distinguishing feature — both lesions typically expose yellowish dentin.
- C. Incorrect. Both abfraction and abrasion classically occur at the cervical area of teeth — location alone does not distinguish them.