Enamael Protection by Hydroxyapatite Toothpaste

Abstract

Tooth enamel comprises ∼90% substituted hydroxyapatite (Ca10(PO4)6(OH)2), HAP, which is continually subjected to consecutive cycles of dissolution and recrystallisation. Initial dental caries is denoted by non-cavitated white spot lesions (WSLs) when net demineralisation occurs. Commercial products such as toothpastes, mouthwashes and chewing gums that release bioavailable calcium, phosphate and/or fluoride species have been shown to facilitate the remineralisation and repair of initial WSLs. In this respect, synthetic HAP particles can be incorporated into toothpastes to exploit both their abrasive and remineralising properties. The present study investigates the potential of a toothpaste containing micron-sized HAP particles (mirasensitive hap+®, Hager Werken, Germany) to repair WSLs in human enamel under optimum pH-neutral conditions and to protect the enamel exposed to an aggressive acid-challenge regime in vitro