Regional differences and some background factors in relation to periodontal health in the Finnish population aged 30 years and over.
D000328:Adult; D000368:Aged; D004522:Educational Status; D005260:Female; D005387:Finland; D006801:Humans; D008297:Male; D008875:Middle Aged; D010510:Periodontal Diseases / Q000453:epidemiology*; D011897:Random Allocation; D012959:Socioeconomic Factors