Delivery of active agents from chewing gum for improved remineralization.

Most surrogate measures of caries were developed to test products containing fluoride, typically at relatively high and closely controlled oral concentrations. However, since the primary mechanism for the remineralization of early enamel caries lesions by chewing gum is through stimulation of saliva, delivering Ca and Pi to the demineralized enamel lesion, established methods may lack the sensitivity to detect the additional benefit of an active agent without the strong remineralizing potential of fluoride. Issues related to the release of active agents from the gum matrix, dilution in the saliva, and limited oral retention time, along with taste, safety, regulatory, and cost concerns, impose further limitations. This paper reviews the efficacy of some active agents used in chewing gum for improved remineralization and includes results from in situ testing of calcium-containing gums, including calcium lactate, tetracalcium phosphate/dicalcium phosphate anhydrous, calcium citrate/encapsulated phosphate, and a calcium lactate/sodium phosphate blend. Despite promising in vitro data from these agents, they did not provide consistently superior results from in situ testing. There is a need to develop better predictive in vitro models for chewing gum, as well as improved sensitivity of in situ models to discriminate relatively small amounts of remineralization against a background of high biological variability.

History of frequent gum chewing is associated with higher unstimulated salivary flow rate and lower caries severity in healthy Chinese adults.

This was a single-center, prospective, cross-sectional study stratified by age and gender with the objective of determining the relationship between gum chewing history, salivary flow, and dental caries severity in adults. We enrolled 191 subjects aged 18-65 years who underwent assessments for gum chewing history, unstimulated salivary flow rate, salivary pH, and caries severity. Unstimulated salivary flow rate tended to decline with increasing age (p = 0.04), and significant differences in unstimulated salivary flow rate were also found for males (0.58 ± 0.32 ml/min) versus females (0.48 ± 0.30 ml/min) (p = 0.02). Weekly gum chewing frequency was greater in younger subjects (p = 0.001) while no age group differences were noted in pieces per day or chewing duration. Gum chewing habits were similar in males and females. A multivariate model demonstrated that only days per week chewing gum (p < 0.001) and gender (p = 0.007) were predictive of unstimulated salivary flow rate (R(2) = 0.40). Mean caries severity scores, assessed via ICDAS II and DMFT, increased with age. In multivariate analysis, age was positively associated with ICDAS (p = 0.001) and days per week chewing gum was negatively associated with ICDAS (p = 0.004), indicating that caries severity increased with age, and that days of chewing provided an inverse effect, with increased days of chewing being associated with decreased severity of caries. Overall, a history of frequent gum chewing is associated with higher unstimulated salivary flow rate and lower caries severity.