Recent Advancements in Preventing Teeth Health Hazard: The Daily Use of Hydroxyapatite Instead of Fluoride

Hydroxyapatite (HA) is commonly considered the most promising synthetic biomaterial for biomedical applications in orthopaedic, dental and maxillofacial surgery for its biocompatibility, bioresorption and bioactivity. Only recently a chemical-physical experimental approach has been utilized to investigate the capability of synthetic carbonated hydroxyapatite nanocrystals (CHA) to produce in vivo biomimetic mineral deposition on enamel and dentine surface through a daily use. Demineralised enamel and dentine slabs have been treated in vitro with synthetic biomimetic hydroxyapatite nanocrystals for a few minutes. This induced a surface remineralisation, forming a biomimetic apatite coating on enamel and dentine surface. In fact, enamel remineralisation quickly occurs thanks to the specific chemicalphysical characteristics of innovative nanostructured hydroxyapatite particles which closely resemble mineral enamel constituents. Therefore the experimental results suggest the possibility to perform teeth wear-deterioration prevention. Carbonated hydroxyapatite nanocrystals synthesized with tailored biomimetic characteristics for composition, structure, size and morphology can chemically bind themselves on the surfaces of teeth hard tissues, filling the scratches, producing a bound biomimetic apatitic coating, protecting the enamel surface structure. Over the past few decades many products for dental damage prevention (toothpastes, rinses and gels) have been commercialized and patented expressly for the fluoride remineralisation effect. Only recently the numerous applications of hydroxyapatite as bone filler biomaterial for implantation surgery have evidenced innovative and important opportunities for decay prevention through a daily use of oral care products containing hydroxyapatite. The aim of this paper is to review these recent patents and classify them according to their actual possibilities to safeguard teeth health.