The Remineralization Research Of Nano-hydroxyapatite

To identify the effect of the nano-hydroxyapatite on the artificial caries model , bovine enamel samples were exposed to the artificial PH cycle in vitro,during which the samples were treated with nano-hydroxyapatite or a combined agent containing both nanohydroxyapatite and sodium fluoride twice a day, with the control group treated with a solution of hydroxyapatite or a fluoride solution with a density of 1000mg/kg.The surface microhardness of these samples are measured before the exposure and after 1-day,3-day 7-day and 15-day exposure. The changes of the surface microhardness are studied. There exists statistically significant difference between the changes of microhardness of different groups, and the nano-hydroxyapatite as well as the combined agent of nanohydroxyapatite and sodium fluoride shows an anti-decalcification effect approximately equaling that of a fluoride solution with a density of 1000mg/kg,which has a much better anti-decalcification effect than that of the solution of pure water and that of the solution of ordinary hydroxyapatite. We can conclude from the research that nano-hydroxyapatite and the combined agent of nanohydroxyapatite and sodium fluoride have reliable anti-caries effects in vitro.