Polyols and remineralisation of enamel subsurface lesions

Abstract

Sugar-free chewing gum containing polyols has been demonstrated to reduce caries experience in randomised controlled clinical trials. A range of polyols (mannitol, sorbitol, xylitol and maltitol) can be found in sugar-free gums and it has been claimed that they can facilitate calcium uptake into enamel subsurface lesions promoting remineralisation. ObjectivesThe aim of this study was to compare the effect of polyols on remineralisation of enamel subsurface lesions in vitro by artificial saliva (AS) and by AS containing the salivary biomimetic casein phosphopeptide amorphous calcium phosphate (CPP-ACP). MethodsThe polyols (12.6% w/v) and CPP-ACP (0.376% w/v) were used at physiologically relevant concentrations approximating those released into saliva during chewing a CPP-ACP/polyol chewing gum. Enamel subsurface lesions were exposed to one of the polyols (xylitol, sorbitol, maltitol, mannitol) in AS or AS containing CPP-ACP for 7days at 37°C with a change of solution each day. Remineralisation of the enamel subsurface lesions was measured by transverse microradiography. ResultsA statistical test for equivalence showed there was no difference in remineralisation between the AS solutions with or without any of the polyols. The AS+CPP-ACP solution substantially promoted remineralisation over AS alone independently of any polyol added. ConclusionThis controlled in vitro study showed that polyols at physiologically relevant concentrations did not promote remineralisation of enamel subsurface lesions by facilitating calcium uptake into the lesion.