Study on the mechanical properties of hydroxyapatite bone cement

Abstract

Aim: To explore the possibility of increasing compressive strength of hydroxyapatite(HA) bone cement by improving the composition of the liquids for hardening. Methods: The powder of cement which was composed of α-tricalcium phosphate (α-TCP) and HA were synthesized from calcium phosphate, calcium carbonate and dicalcium phosphate dihydrate by solid reaction; The liquids for hardening were different proportion of aqueous solutions prepared by adding citrate and/or copolymer solutions of acrylic acid/itaconic acid into citric acid. Results: The cement could be hardened when the liquid for hardening was composed of citric acid solution. However the compressive strength of 24.96 MPa was only recorded. After adding appropriate citrate into the liquid, compressive strength of cement was improved, reaching a maximum of 35.60 Mpa. After the liquid was prepared by mixing citric acid/citrate solution and copolymer solution of acrylic acid/itaconic acid at the ratio of 1:2, the compressive strength of the hardened cement was very significantly improved, reaching a maximum of 116.98 MPa. Conclusion: Compressive strength of HA bone cement can be obviously improved and modified when the liquid for hardening is composed of citrate and copolymer solution of acrylic acid/itaconic acid.