Oral mucosal changes related to plasma ascorbic acid levels.

The role of vitamin C in maintaining mucosal health is poorly documented. The purpose of this study was to examine the presence of oral mucosal lesions in subjects with low ascorbic acid (AA) levels in plasma. AA plasma levels of 843 working elderly people in six rural villages in Eastern Finland were determined. All subjects with low plasma AA levels (< or = 25 mumol/l) (n = 106) formed the study group. Controls with normal AA levels (> or = 50 mumol/l) (n = 103) were drawn from the same population. They were matched for age, sex and number of teeth. Oral mucosal lesions in all subjects were recorded clinically using a double-blind method in all subjects. Petechias, leukoplakia and lichenoid lesions were the commonest lesions of the oral mucosa. Only in leukoplakia there was a statistically significant difference between the groups (p < 0.01). Smokers had more leukoplakia than non-smokers. The prevalence of leukoplakia was higher when smoking was combined with AA deficiency.