Periodontal Disease

Periodontal disease is causally related to anaerobic bacteria. Tissue damage occurs as a result of complex molecular interactions between pathogenic bacteria and host immune responses. In susceptible patients, both local and systemic factors affect the pathogenesis of the infection. Vitamin C deficiency has been shown histologically to result in a lack of collagen formation by affecting the hydroxylation of proline and increasing the permeability of the oral mucosa to endotoxins.9 Vitamin C also enhances the mobility of polymorphonuclear leukocytes, and a deficiency of vitamin C is associated with decreased host immune responses.10,11

Animals placed on a diet deficient in vitamin C exhibit adverse changes in the periodontium related to a lack of collagen formation characterized by degenerative soft and hard tissue changes, distorted nuclear morphology of polymorphonuclear leukocytes, and reduced chemotactic responses.12,13,14,15

Vitamin C has long been a candidate for modulating periodontal disease. A recent study, which evaluated the role of dietary vitamin C as a con tributing factor for periodontal disease, has shown there is a relationship between reduced dietary vitamin C and increased risk for periodontal disease in the general population (odds ratio [OR] = 1.19; 95 % Cl: 1.05 to 1.33).16 The study has also shown current and former tobacco users who were taking less dietary vitamin C had an increased risk of periodontal disease with an OR of 1.28, 95 % Cl: 1.04 to 1.59 for former smokers, and an OR of 1.21, 95 % Cl: 1.02 to 1.43 for current tobacco users. The dietary intake of vitamin C showed a weak but statistically significant relationship to periodontal disease in current and former smokers as measured by clinical attachment. Those taking the lowest levels of vitamin C, and who also smoke, are likely to show the greatest clinical effect on periodontal tissues. Since smokers already are at greater risk for periodontal disease independent of vitamin C intake and oxidants from cigarette smoking lower vitamin C concentrations in blood, it can be hypothesized smokers require higher levels of dietary vitamin C intake.

Dental Caries

Ascorbic acid affects in vitro growth of bacteria and may also act in vivo to decrease caries activity. A doubleblind study has evaluated the possible association between vitamin C in plasma, the number of carious lesions, the relative numbers of selected species of the oral cariogenic flora, and the rate of salivary secretion.16 The caries status and selected bacteriological variables of dentate adult subjects with low levels of vitamin C in plasma (< or = 25 mumol/L) were compared with those of controls (plasma levels of vitamin C > or = 50 mumol/L) matched for age, sex, and number of teeth. The study concluded the amount of visible plaque and the number of decayed tooth surfaces were significantly higher in the low vitamin C group.