The use of sugar-free gum provides a proven anti-caries benefit, but other oral health effects are less clearly elucidated. Chewing sugar-free chewing gum promotes a strong flow of stimulated saliva, which helps to provide a number of dental benefits: first, the higher flow rate promotes more rapid oral clearance of sugars; second, the high pH and buffering capacity of the stimulated saliva help to neutralise plaque pH after a sugar challenge; and, lastly, studies have shown enhanced remineralisation of early caries-like lesions and ultimately prospective clinical trials have shown reduced caries incidence in children chewing sugar-free gum. This paper reviews the scientific evidence for these functional claims and discusses other benefits, including plaque and extrinsic stain reduction, along with the possibility of adding specific active agents, including fluoride, antimicrobials, urea and calcium phosphates, to enhance these inherent effects. The evidence for a specific effect of xylitol as a caries-therapeutic agent is also discussed. In conclusion, it is asserted that chewing gum has a place as an additional mode of dental disease prevention to be used in conjunction with the more traditional preventive methods.