Dissolution Resistance of Bovine Teeth-Derived Hydroxyapatite

Abstract

Dissolving behavior of hydroxyapatite ceramics prepared from bovine teeth (BTHA) was investigated. The bovine teeth were soaked in 0.1 M of NaOH at 80°C for 1 h. After soaking, the teeth were calcined at 800°C for 1 h, and then they were attritor-milled for 24 h. BTHA powder consisted of mainly HA and small amount of MgO. The powders obtained were cold isostatically pressed and sintered at 1200°C with a dwell time of 1 h. Sintered density of BTHA was about 70%. After polishing the surface of sintered specimen, BTHA was immersed in buffered water at 37°C for 3 and 7 days. After immersion period, there is no evidence of dissolution for BTHA at the end of the immersion time. In addition, there is no change of peak intensity in XRD after immersion time. It was found that hydroxyapatite from bovine teeth was more stable than commercial HA in liquid environment.