School of Engineering and Materials Science
Research Student Awards
PhD Thesis: Use of biomaterial particulates in bone repair.
Author: MUSHIPE, Moses
Supervisor(s): Julia Shelton
In this thesis, particles of approximately 230 by 140 m were prepared from three sources, namely, rabbit cancellous bone, sintered bovine cancellous bone, commercially known as Endobon® and commercial hydroxyapatite, and used to treat bone defects.
The influences of Endobon® and hydroxyapatite particles on the healing of cancellous bone defects in the femoral condyles of rabbits was investigated at 5 and 15 weeks post-surgery. At 5 weeks, the stiffness and hardness properties of the Endobon® filled defects were higher than both the empty, control defects (p < 0.05) and the hydroxyapatite filled defects (p < 0.01). Histologically, more bone was seen surrounding Endobon® than hydroxyapatite particles, however no significant differences were observed in either the percentage bone contact or the appositional rate values of the de novo bone. By 15 weeks the mechanical properties from all the groups were similar. At 5 weeks after surgery, the effects of Endobon® and allograft bone particles on the healing of 1 mm wide cortical bone osteotomies created in the diaphyses of the rabbit fibulae were studied. The properties of both Endobon® and allograft filled osteotomies were not significantly different from the untreated control or intact fibulae. However, bone fluorochrome labels administrated at 2 weeks showed new bone growing in osteotomies treated with particles earlier than the controls, suggesting that the mechanical properties might have been different.
Endobon® particles have been shown to accelerate bone healing. However, the controlling parameters that influence the rapid repair processes need to be isolated. Furthermore, the development of an injectable system is imperative.