Is sugar-free confectionery good for your teeth?

Objectives: Sugar-free confectionery is promoted as a healthy alternative to other sweets as it contains non-fermentable carbohydrates that cannot be metabolised by oral bacteria to generate acid. Several of these sweets contain acid however, and the objective of this study was to measure the effect of the confectionery on saliva pH in vitro. Methods: The acid content of eleven types of sugar-free confectionery was measured. The effect of incubating whole saliva samples from four individuals with the sugar-free confectionery on saliva pH was determined. The rate of change of saliva pH, and the time taken to reduce the pH of saliva samples to a value of 5.5, was measured. The degree to which the confectionery stimulated saliva flow was also measured. Results: Fruit-flavoured confectionery contained more acid than mint- or licorice-flavoured confectionery. Saliva pH dropped most quickly when incubated with fruit-flavoured confectionery, with the shortest time to reduce salivary pH to 5.5 being 1.5 minutes. Smint mints did not reduce saliva pH. All flavours of sugar-free confectionery stimulated saliva flow. Conclusions: Although sugar-free confectionery does not allow acid generation by oral bacteria, fruit-flavoured sweets rapidly reduce saliva pH in vitro. Mint-flavoured confectionery did not reduce saliva pH yet still stimulated saliva flow therefore it may be recommended for use by dry-mouth patients. This work was supported by a Univrsity of Otago Oral Microbiology and Dental Health Research Theme summer studentship awarded to N.-C.Y.