A clinical photograph shows isolated, localized recession on a single mandibular anterior tooth with the adjacent teeth unaffected. What is the most likely cause?

Correct answer: A. Localized trauma — aggressive toothbrushing and/or a thin biotype over a prominent root

• A. Correct. ISOLATED single-tooth recession with clinically healthy adjacent tissue points to a LOCAL mechanical/anatomic cause: aggressive horizontal toothbrushing, a thin gingival biotype, a prominent or labially positioned root with thin or dehisced buccal bone, high frenum pull, or occlusal trauma. Treatment addresses the cause first (brushing technique), then a connective tissue graft if coverage is needed.
• B. Nutritional deficiency produces generalized gingival changes, not a single isolated defect.
• C. Periodontitis causes GENERALIZED attachment loss with pocketing and bone loss — not isolated recession on one tooth with healthy neighbours.
• D. Occlusal caries is a separate process and does not produce gingival recession.