title: Effect of nano-hydroxyapatite concentration on remineralization of initial enamel lesion in vitro.
abstract: The purpose of the research was to determine the effect of nano-hydroxyapatite concentrations on initial enamel lesions under dynamic pH-cycling conditions. Initial enamel lesions were prepared in bovine enamel with an acidic buffer. NaF (positive control), deionized water (negative control) and four different concentrations of nano-hydroxyapatite (1%, 5%, 10% and 15% wt%) were selected as the treatment agents. Surface microhardness (SMH) measurements were performed before/after demineralization and after 3, 6, 9 and 12 days of application, and the percentage surface microhardness recovery (%SMHR) was calculated. The specimens were then examined by a scanning electron microscope. The %SMHR in nano-hydroxyapatite groups was significantly greater than that of negative control. When the concentration of nano-HA was under 10%, SMH and %SMHR increased with increasing nano-hydroxyapatite concentrations. There were no significant differences between the 10% and 15% groups at different time periods in the pH-cycling. The SEM analysis showed that nano-hydroxyapatite particles were regularly deposited on the cellular structure of the demineralized enamel surface, which appeared to form new surface layers. It was concluded that nano-hydroxyapatite had the potential to remineralize initial enamel lesions. A concentration of 10% nano-hydroxyapatite may be optimal for remineralization of early enamel caries.
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, People's Republic of China.
authors.forename: S B
authors.initials: SB
authors.lastname: Huang
authors.forename: S S
authors.initials: SS
authors.lastname: Gao
authors.forename: H Y
authors.initials: HY
authors.lastname: Yu
mesh_terms: D000818:Animals; D001857:Bone Matrix / Q000187:drug effects*; D002113:Calcification, Physiologic / Q000187:drug effects*; D002417:Cattle; D003731:Dental Caries / Q000188:drug therapy* / Q000503:physiopathology*; D003743:Dental Enamel / Q000187:drug effects*; D017886:Durapatite / Q000008:administration & dosage*; D005240:Feasibility Studies; D066298:In Vitro Techniques; D053758:Nanoparticles / Q000008:administration & dosage*
chemical_list: D017886:Durapatite