A study on the surface strain distribution on the hydroxyapatite-implanted canine tibia: a preliminary report

It has been said by many investigators that hydroxyapatite ceramics may be prospective bone substitute materials. Its mechanical brittleness and strength has been the most serious consideration. In the present article a study has been done using animal experiments, the changes of surface strain at the hydroxyapatite implantation site of long-bone when the compressive stress is applied in the direction of long axis, in order to clarify the mechanical behaviors of hydroxyapatite living bone complex. The nonimplanted side was used as the control. Results revealed that the hydroxyapatite living bone complex has been proven to have sufficient flexibility such that it shows no hysteresis in stress versus strain relation up to 200 kg of applied load. The strain distribution pattern on the HA-implanted bone is quite similar to that of the nonimplanted one. This characteristic also suggests that it has normal skeletal function.