Tooth #23 has localized recession without any signs of periodontal disease. What is the MOST likely cause of this isolated recession?

Correct answer: D. Mechanical abrasion (toothbrushing trauma)

• A. Orthodontic movement can cause recession if teeth are moved outside the alveolar housing, but there is no mention of orthodontic treatment.
• B. If the recession were caused by periodontitis, there would be expected BOP, bone loss, and involvement of adjacent teeth. The generalized gingivitis (without attachment loss) does not explain single-tooth recession.
• C. Drug-induced gingival changes (from antiepileptics, calcium channel blockers, cyclosporine) cause gingival ENLARGEMENT, not recession.
• D. CORRECT. Isolated recession on a single tooth in the absence of generalized periodontal disease is most commonly caused by MECHANICAL ABRASION — incorrect toothbrushing technique (horizontal scrubbing, hard bristles). Tooth #23 (lower anterior) is a common site for recession from abrasion due to its prominent buccal position.