Written by Susan Sweeny Johnson, PhD, Biochem.
Dental caries are caused by the fermentation of sugar left on the teeth after eating. This produces acid in the mouth, which eats away tooth enamel. Chewing sugared gum has been clearly shown to cause tooth decay. (1) Replacing the sucrose in chewing gum with a non-fermenting sugar should prevent the formation of dental caries. Additionally, the chewing motion itself stimulates the flow of saliva which prevents the formation of mouth acids. (2)
In the Burt, et al (3) review of randomized field studies from 1984 to the present, chewing gum containing sorbitol rather than sucrose was shown to reduce the presence of dental caries somewhat. Sorbitol is only partially fermented by streptococcus mutans, the mouth bacteria known to cause dental caries. Two large studies showed that compared to not chewing gum, chewing gum containing sorbitol three times a day after eating for 5-20 minutes reduced dental caries either 33% or 8%. (4,5) Gum containing xylitol achieved even better results.
Xylitol is nearly as sweet as sugar and cannot be fermented at all by strep mutans, so no mouth acid is formed. In the Milgram et al. study, (6) as in numerous others, ( 7) xylitol causes the amount of strep. mutans in the mouth to drop. The randomized study included 132 patients using a sorbitol/manitol gum control compared with increasing amounts of xylitol (3.44 -132 g per day). The patients chewed the gum four times a day. Saliva and plaque were assessed for strep.mutans at the start, at five weeks and at six months.
After five weeks of gum chewing, the amount of strep. mutans in the plaque was 10 times lower than at the start while the amount in the saliva stayed the same when more than 6.88 gm/day of xylitol was consumed in gum. After 6 months, no further drop in plaque bacteria was seen but the amounts of strep. mutans in the patient’s saliva dropped ten times again when more than 6.88 gm/ day was chewed.
Other studies comparing xylitol gum, sorbitol gum and no gum chewed 3 times a day showed some to moderate reduction in dental caries particularly with xylitol gum. (8, 9, 10)
One interesting Finnish study (11) of 195 mother-infant pairs showed that mothers who chewed xylitol gum passed on far less strep. mutans to their infants even up to 5 years of age. The control group of mothers received only fluoride or chorhexidine mouth washes. The children received no treatment but the number of dental caries in the children wa decreased 70% when the mothers chewed the gum. Three other studies had similar results. (12, 13, 14)
Overall, it was recommended that people who chew gum switch to a xylitol-sweetened gum. Even non-gum chewers could benefit from chewing xylitol gum after meals.
Source: “The Use of Sorbitol and Xylitol Sweetened Chewing Gum in Caries Control.” JADA 2006; 137(2):190-6 and “Mutans Streptococci Dose Response to Xylitol Chewing Gum” , J Dent. Res. 2006; 85(2):177-181. Posted August 8 , 2008.
- Glass RL. Effects on dental caries incidence of frequent ingestion of small amounts of sugars and stannous EDTA in chewing gum. Caries Res 1981;15:256-62.
- Edgar WM, Geddes DA. Chewing gum and dental health: a review. Br Dent J 1990;168(4):173-7.
- Burt, Brian A, et al. The Use of Sorbitol and Xylitol Sweetened Chewing Gum in Caries Control: JADA 2006; 137(2):190-6.
- Badet MC, Richard B, Dorignac G. An in vitro study of the pH lowering potential of salivary lactobacilli associated with dental caries. J Appl Microbiol 2001;90:1015-8.
- Szoke J, Banoczy J, Proskin HM. Effect of after-meal sucrose-free gum-chewing on clinical caries. J Dent Res 2001;80:1725-9.
- Milgrom P., et al, “Mutans Streptococci Dose Response to Xylitol Chewing Gum” J Dent. Res 2006; 85(2):177-181.
- Edgar WM. Sugar substitutes, chewing gum and dental caries: a review. Br Dent J 1998;184(1):29-32.
- Mäkinen KK, Bennett CA, Hujoel PP, et al. Xylitol chewing gums and caries rates: a 40-month cohort study. J Dent Res 1995;74:1904-13.
- Mäkinen KK, Hujoel PP, Bennett CA, Isotupa KP, Mäkinen PL, Allen P. Polyol chewing gums and caries rates in primary dentition: a 24-month cohort study. Caries Res 1996;30:408-17.
- Hildebrandt GH, Sparks BS. Maintaining mutans streptococci suppression with xylitol chewing gum. JADA 2000;131:909-16.Isokangas P, Söderling E, Pienihakkinen K, Alanen P. Occurrence of dental decay in children after maternal consumption of xylitol chewing gum, a follow-up from 0 to 5 years of age. J Dent Res 2000;79:1885-9.
- Söderling E, Isokangas P, Pienihakkinen K, Tenovuo J. Influence of maternal xylitol consumption on acquisition of mutans streptococci by infants. J Dent Res 2000;79:882-7.
- Söderling E, Isokangas P, Pienihakkinen K, Tenovuo J, Alanen P. Influence of maternal xylitol consumption on mother-child transmission of mutans streptococci: 6-year follow-up. Caries Res 2001;35(3):173-7.
- Thorild I, Lindau B, Twetman S. Effect of maternal use of chewing gums containing xylitol, chlorhexidine or fluoride on mutans streptococci colonization in the mothers’ infant children. Oral Health Prev Dent 2003;1(1):53-7.