the invention relates to nano - sized complexes formed by associating amorphous calcium phosphate and / or amorphous calcium fluoride phosphate with an amphiphilic polymer surfactant . the amphiphilic polymer surfactants can form nano - sized assemblies in aqueous solution , serving as a nano dispersant preventing acp and / or acfp from aggregation , and as a nano carrier associating or attaching acp and / or acfp , stabilizing acp and / or acfp against the conversion to a crystalline form as well , thus maintaining calcium and phosphate / and fluoride ions in a bioavailable state for dental re - mineralization and prevention of dental caries , dental calculus and dental hyper - sensitivity . a method for the nano - sized complex preparation and compositions comprising the nano - sized complexes are also provided .