Socioeconomic status and recurrent aphthous ulcers.
D005260:Female; D006801:Humans; D008297:Male; D012924:Social Conditions; D013223:Statistics as Topic; D013281:Stomatitis, Aphthous / Q000453:epidemiology*; D013335:Students, Dental; D013337:Students, Medical; D013338:Students, Nursing