Local changes in aluminium, calcium and phosphorus content of bone caused by alumina implant

Thirty rabbits were divided equally into 5 groups randomly. A hole, 6 mm in diameter and 2 mm deep, was bored on each iliac crest. Two pieces of alumina were implanted into the hole of one side, while the opposite side served as control. These rabbits were killed on 10, 20, 40, 60 and 90 days after operation. Calcium, phosphorus and aluminium contents of iliac bone on both sides were determined by Inductively Coupled Plasma--Atomic Emission Spectrometry. The results showed that the aluminium content of the implanted side in each group was higher than that of the control and difference was significant in 10, 40 and 60 day groups (P < 0.05). This shows that the implant releases aluminium into the bone. Moreover, the calcium and phosphorus contents were significantly lower on the implanted side than on the control side in 10 and 20 day groups (P < 0.05-0.001). Apparently, the aluminium released from the implant in the early stage can interfere with the local calcium and phosphorus metabolism and delay the mineralization of the bone.