Abrasion is best described as wear caused by which?

• A. Toothbrush wear
• B. Acid erosion
• C. Microfracture
• D. Tooth-to-tooth wear

Answer: (A)

Abrasion is wear caused by a mechanical action from something external to the tooth, most commonly a brushing action. The classic example is toothbrush wear, where repeated brushing with an abrasive toothpaste or improper technique wears away tooth structure, often creating notches near the gum line (cervical area). This reflects the idea that abrasion results from external physical contact that grinds away at the surface.

Acid erosion, by contrast, is chemical wear from acids dissolving mineral content—not mechanical rubbing. Microfracture refers to cracks from stress, not gradual surface wear. Tooth-to-tooth wear describes attrition from opposing teeth grinding together, which is wear from tooth-to-tooth contact rather than an external abrasive agent.