Xylitol content and acid production of chewing gums available in the markets of Saudi Arabia

To assess the actual xylitol content in sugar-free chewing gums available in a market of Saudi Arabia and investigate its effect on acid production and pH change in vitro. Materials and methods: A total of 29 different brands of xylitol-containing sugar-free chewing gums were collected from five major grocery stores in Saudi Arabia. Xylitol was extracted and its concentration was determined using the D-Sorbitol/Xylitol Enzymatic Kit (Megazyme; Bray, Wicklow, Ireland). The pH of the extracts and the amount of acid production for each product was measured after 15-minute and 30-minute incubation with Streptococcus mutans. Descriptive analysis, concentrations, and one-way analysis of variance (ANOVA) with the least significant difference (LSD) as multiple comparisons were performed. Results: The xylitol content in grams was clearly stated on the labels of 16 products, while it was stated in percentages on the labels of ten products. The mean pH of most of the tested products was 5.857 ± 0.096. Significant differences in pH were recorded among 20 products (p ≤ 0.05). Highly significant differences in pH (p = 0.001) were observed in five of the products. Conclusion: The results of this study indicate, using an in vitro model, that xylitol can significantly affect salivary pH. The actual xylitol content in most brands of chewing gums currently available in the markets of Saudi Arabia is less than the concentration recommended for prevention of caries. Accurate information with proper labeling is required to enable dental professionals to take correct and informed decisions about recommending the use of these products.