GROSS AND HISTOMORPHOLOGICAL STUDY OF BONE CEMENT AND BONE GRAFT IN DOG

D.Sharifi,Ph.D, GH.R.Abedi,Ph.D, F.Sassani,Ph.D, D.Savadkouhi,M.D, I.Nowrouzian,M.V.P.M, J.Bakhtiari Ph.D.

Various biological bone grafts have been used for osteogenesis, osteoconduction and even osteoinduction, but due to systemic influences and local factors the outcome of successful incorporation of a bone graft has not been so satisfactory. So this study was conducted on 15 clinically healthy adult dogs between 1 to 3 years of age and 20 to 30 kg/BW to evaluate the effect of bone cement and autogenous bone graft. The piece of 3 Cm complete mid-shaft left tibial cortical bone was removed in all animals then they were divided into three groups of 5 animals each. In group I the bone was fixed with suitable intramedullary pin, whereas the gap was filled up with harvested autogenous rib bone in group II animals. The bone cement was used to fill up the gap in animals group III for first 30 days then it was replaced with iliac chip bone and observation was made accordingly for 60 days in all animals of three groups. On 60 days before collection of callus sample, grossly there was granulation and fibrocartilage tissues in group I & II and the thick fibrous capsule around bone cement on 30 days and on 60 days in group III animals. There was combination of collagen fibers beside hypertrophic chondroblasts in histomorphological cross section in group I animals, whereas active osteoblast mixed with sequestra in animals group II. Fibrotic capsule, periosteal layer, lacunae, osteoblast, osteocyte and well formed bone marrow with RBC and adipose tissue were noted in animals group III. The bone cement leading to fibrotic capsule formation was quite helpful to delay iliac bone graft resorption and enhancing osteogenic stimulation as to fill the gap with impact callus with normal cortical structure. The application of bone cement in gap nonunion, crushed bone and fragmental fractures is highly recommended.