Degradation Characteristic of Strontium-Containing Calcium Phosphate Cement in vivo

The objective of this study is to compare the degradation of three strontium-containing calcium phosphate cement (Sr-CPC) and one calcium phosphate cement without strontium (CPC) in vivo. Three Sr-CPCs, containing 1%, 5%, 10% strontium respectively, and a CPC without strontium were tested in this study. The specimens in rod-shape (2 mm x 6 mm) were prepared, and were implanted in the erector spine muscle of 15 New Zealand rabbits. After 4, 8 and 12 weeks, 5 rabbits were sacrificed respectively and the specimens were taken out, cleaned, dryed and weighed. The weight losses of the specimens were calculated and the data were analyzed by ANOVA. The results showed that the CPC containing 5%, 10% strontium showed obviously higher degradation rates at the three observation periods than that containing 1% strontium and that without strontium (P<0.05). Addition of 1% strontium into CPC did not increase degradation rate (P>0.05), and the CPC containing 5% and 10% strontium showed no difference in degradation rate at the three observation periods (P>0.05).