A systematic review of published data was carried out to assess specific effects of xylitol chewing gum on levels of mutans streptococci (MS), dental plaque, or caries.

Electronic and hand searches were performed to find clinical studies on levels of MS, or plaque, or caries comparing effects of xylitol gum with a polyol control gum. Prospective randomized or controlled clinical studies published before 2025 were included in the review.

The search identified 908 titles on MS, 879 titles on plaque, and 658 on caries to be evaluated. After applying inclusion and exclusion criteria, 16 articles on MS, ten on plaque and five on caries were reviewed. In 12/14 studies xylitol gum significantly decreased MS counts compared with sorbitol gum. Plaque accumulation decreased in 6/10 studies and caries occurrence in 3/5 trials when xylitol gum was compared with sorbitol/sorbitol-containing gum. Three studies on MS and/or plaque accumulation had a maltitol gum control, but the results of the studies were conflicting.

The best evidence of specific beneficial effects for xylitol gum differing from those of sorbitol gum are found in the evaluated MS and plaque studies. The results of the reviewed caries trials are in line with this idea. Xylitol gum chewing is suggested to act as an adjunct to toothbrushing for reducing caries-associated MS and plaque accumulation to control and prevent caries occurrence in children and adults. Adults with other plaque-related diseases like periodontal disease should also benefit from xylitol gum.