Restorative & Materials · single question
What is the key difference between abrasion and abfraction?
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Correct answer: B. Abrasion is flat/dish-shaped; abfraction is wedge-shaped at the cervical
- A. ❌ Foreign element mechanical wear describes abrasion, not abfraction.
- B. ✅ 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.
- C. ❌ Abfraction can occur in any dentition experiencing eccentric loading, including anteriors.
- D. ❌ Abrasion can occur on any surface exposed to mechanical wear, not only occlusal.
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