Gingival ulceration due to improper toothbrushing.
D000293:Adolescent; D000328:Adult; D003937:Diagnosis, Differential; D005882:Gingival Diseases / Q000209:etiology*; D006801:Humans; D008297:Male; D014099:Toothbrushing / Q000009:adverse effects*; D014456:Ulcer / Q000209:etiology