By Sok-Ja Janket, DDS, MSEditor’s note: In recent research published in the British Dental Journal, scientists concluded that polyol-based sugar-free products may decrease the incidence of dental caries, but they may bring about another dental health risk — dental erosion — if the products contain acidic flavoring. Properly conducted clinical studies are needed in this area. Xylitol, as well as many other sugar alcohols, has been termed as nonfermentable sugars in the literature. However, some of these nonfermentable sugar alcohols can be metabolized by S. mutans and other strains of oral microorganisms. Many studies have shown that some bacteria are capable of fermenting sugar alcohols to some degree, which will lead to acid production and ultimately tooth decay, but in a lesser degree than table sugar.1,2There are three notable properties of xylitol that have made it an important sugar alcohol in dental research:
- Most importantly, xylitol is not readily fermented by oral bacteria, especially the species of Streptococci mutans.
- It has also been shown to reduce the amount of S. mutans in the oral cavity by limiting the source of fermentable substrates for these bacteria to survive.
- Xylitol can induce the production of salivary enzymes, which lead to the inhibition in growth of bacteria in plaque.
Dr. Sok-Ja Janket is an associate research professor at Boston University Henry M. Goldman School of Dental Medicine (GSDM) and lead researcher on the xylitol project.References1. Edwardsson S, Birkhed D, Mejare B. Acid production from Lycasin, maltitol, sorbitol and xylitol by oral streptococci and lactobacilli. Acta Odontol Scand. 1977; 35(5):257-263.2. Kalfas S, Edwardsson S. Effect of culture medium on acid production from sorbitol by oral bacteria. Acta Odontol Scand. 1990; 48(4):217-222.3. Ericsson Y, Oberg H. A nomogram for the determination of calcium phosphate saturation and critical pH level in the saliva. Acta Odontol Scand. 1952; 10(2):67-70.4. Kleber CJ, Putt MS, Muhler JC. Enamel dissolution by various food acidulants in a sorbitol candy. J Dent Res. 1978; 57(3):447-451.5. Dawes C. What is the critical pH and why does a tooth dissolve in acid? J Can Dent Assoc. 2003; 69(11):722-724.6. Wagoner SN, Marshall TA, Qian F, Wefel JS. In vitro enamel erosion associated with commercially available original-flavor and sour versions of candies. J Am Dent Assoc. 2009; 140(7):906-913.Additional resources• Nadimi H, Wesamaa H, Janket SJ, Bollu P, Meurman JH. Are sugar-free confections really beneficial for dental health? Br Dent J. 2011; 211(7):E15.• Dawes C, Kubieniec K. The effects of prolonged gum chewing on salivary flow rate and composition. Arch Oral Biol. 2004; 49(8):665-669.