Restorative & Materials · single question
What is the key difference between abrasion and abfraction?
Show answer and explanation
Correct answer: A. Abrasion occurs only on the occlusal surface
- A. Correct. Abrasion creates a flat, dish-shaped lesion from mechanical wear (toothbrush, abrasive foods). Abfraction creates a wedge-shaped notch at the cervical due to eccentric occlusal loading causing enamel microfractures at the fulcrum.
- B. Incorrect. Abrasion can occur on any surface exposed to mechanical wear, not only occlusal.
- C. Incorrect. Foreign element mechanical wear describes abrasion, not abfraction.
- D. Incorrect. Abfraction can occur in any dentition experiencing eccentric loading, including anteriors.
Sources disagree on the answer to this question. Check a trusted reference.
Practice Restorative & Materials questions Restorative & Materials study notes