Xylitol reduces cavity‑causing bacteria and raises salivary flow, which can increase calcium and phosphate availability. That environment supports natural remineralisation and boosts the effect of fluoride or hydroxyapatite products, but xylitol itself doesn’t deposit minerals into enamel.
For actual mineral replacement, look to fluoride toothpaste/varnish, casein phosphopeptide‑amorphous calcium phosphate (CPP‑ACP), or nano‑hydroxyapatite formulations; xylitol gum is a useful adjunct.