Comparative biocompatibility studies of Kirschner wire, allogeneic and canine xenogeneic cadaveric bone tissue implants in rat model

Pre-clinical safety or biocompatibility studies of newer biomaterials intended for clinical use are paramount in medical implant technology. The in vivo safety of rat (allogeneic) and dog (xenogeneic) cadaveric bone implants (CBI) in the present study were assessed through histological and haematological profiles. A total of 12 male Albino rats (average weight 120 g) divided into three groups (A, B & C) of four rats each was used. Rat (allogeneic) and dog (xenogeneic) cadaveric bone implants were surgically placed between the lateral and cranial vastus muscles (on the thigh) of the rats in groups B and C, respectively, while Kirschner wire/inert implants were used for group A and served as control. The rats were monitored for 30 days, and peripheral blood profiles, as well as tissue sections at intervals of 14 and 28 days, were harvested, studied and compared. Results showed that the overall performance of all groups of rats was good. There was marked cellular infiltration of myocytes in rats of groups B and C, and cartilage-like (hyaline) cells in group C at 14 and 28-days post-implantation, respectively. No significant alteration existed in the haemogram of all groups of rats except for the increased lymphocytes count observed in group B pre-implantation. In conclusion, canine CBI used in this study possess fairly excellent biocompatibility and osteoinductive potentials in the rat’s model. Therefore, having confirmed their relative in vivo safety and biocompatibility, further clinical trials involving the use of cadaveric bone tissues as good biomaterial for fabricating bone fixatives should be performed in higher animal models.