This study was carried out on 80 New Zealand white rabbits, each weighing 3-3.5kg. Twenty rabbits were allocated into each of the four groups. After a 1cm sized ostectomy was made on the tibial body with the periosteum preserved, artificial bone substitutes were implanted. Except for control group(I), manufactured chitosan pellets were implanted in group II, Osteoset^(®)(calcium sulfate) in group III and manufactured calcium sulfate-chitosan composite pellets in group IV.
Results were evaluated using radiographic study, bone mineral density test and histologic examination in 2, 4, 6 weeks and three point bending test in 6 weeks after implantation. In the radiographic study, the formation and corticalization of callus were similar in groups III, IV and this was much earlier than in groups I, II. In the bone mineral density test and three point bending test to contralateral normal tibia in 6 weeks, the values in groups III and IV were statistically significantly higher than in groups I and II(p<0.05). In histologic examination, groups III and IV have more abundant and faster new bone formation than groups I and II.
In conclusion, the synergistic effect between calcium sulfate and chitosan in group IV is considered to facilitate new bone formation as effectively as Osteoset^(®) does.
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