Caries Preventive Effect of One-Year Use of Low-Dose Xylitol Chewing-Gum in High-Caries-Risk Adults

This Randomised Clinical Trial investigates the caries preven- tive effect of low-dosage (2.5 g/die) xylitol chewing-gum adminis- tered for one-year in a high-caries-risk adult population. 179 sub- jects (≥1 cavitated lesion and salivary concentration of mutans streptococci (MS) ≥105 CFU/mL) were recruited and randomly assigned to two groups. Polyols group received for one-year gums containing 28% isomalt, 31% sorbitol, 9% mannitol and 1% malti- tol syrup, while xylitol group received gums containing 26% sor- bitol, 11% mannitol and 30% xylitol. Caries status, using the Inter- national Caries Detection and Assessment System, salivary MS, and plaque-pH were evaluated at baseline, at the end of the admin- istration and re-evaluated after one year in 66 xylitol and 64 poly- ols subjects. All participants reported to use a F-toothpaste (1000/1450 ppm) on a regular basis. The net caries increment for initial, moderate and extensive lesions and for the caries experi- ence was evaluated using the nonparametric Mann–Whitney-U- test. The total caries experience increment was 1.25 ± 1.26 in the xylitol group and 1.80 ± 2.33 in the polyols group (p = 0.01). Sub- jects treated with xylitol had a reduction of Risk Rate at tooth lev- el of 23% respect to those treated with polyols with a number need- ed to Treat of 55 teeth. The area under the curve at pH5.7 was sta- tistically significant lower (p = 0.02) in the xylitol group. A decrease of the concentration of salivary MS was noted in xylitol group (p < 0.01).