Hydroxyapatite as an active ingredient in oral care: an international symposium report

Hydroxyapatite, Ca₅(PO₄)₃(OH), is a bioinspired active ingredient for preventive oral health care. The use of hydroxyapatite in the prevention of oral diseases has gained interest, particularly in recent years. Hydroxyapatite can be used in office and for daily oral care (e.g. in toothpastes and mouthwashes). The first clinical efficacy studies on caries prevention and reduction of symptoms of dentin hypersensitivity were conducted in the 1980s. These were followed by various in vitro and in situ studies and several more recent clinical trials. A number of systematic reviews and meta-analyses on the use of hydroxyapatite in preventing oral health problems have been published. Summarizing these data, hydroxyapatite is a versatile active ingredient with multiple benefits that include caries prevention, relief from dentin hypersensitivity and tooth whitening. Since this calcium phosphate mineral has an excellent biocompatibility, it is safe for all patient groups. This interdisciplinary review gives an overview of the developments in hydroxyapatite research, highlights the research progress made regarding hydroxyapatite as a biomimetic active ingredient and summarizes the state-of-the-art evidence in support of hydroxyapatite efficacy.