In vivo biocompatibility and fracture healing of hydroxyapatite-hexagonal boron nitridechitosan-collagen biocomposite coating in rats

The biocompatibility of orthopaedic implants and their effects on fracture healing have key roles for success. In this study, it was aimed to investigate the effects of a novel biocomposite consisting of hydroxyapatite (HA), hexagonal boron nitride (h-BN), chitosan (Cs), and type 1 collagen (Ct1) on biocompatibility and fracture healing in rats. A total of 60 adult male Wistar rats weighing 300–500 g were used in the study. The rats were randomly divided into 2 groups named A (uncoated/control) and B (biocomposite coated). Biocomposite (HA/h-BN/Cs/Ct1) coated and uncoated stainless-steel implants were used as intramedullary pins. Groups A and B were divided into subgroups of A1 and B1 (15th day), A2 and B2 (30th day), A3 and B3 (45th day) according to the date of euthanasia. Clinical, radiographic, haematological, biochemical, and histopathological findings were evaluated by pairwise comparisons. The findings were consistent and similar. No statistically significant difference was found for a finding disturbing the biocompatibility. Histopathological examinations showed that coating biomaterials did not resorb over the course of 15, 30, and 45 days. It is thus revealed that the content is biocompatible. However, it has been concluded that it is necessary to increase the physical strength of the coating surface against sterilization and surgical procedures. As a result, based on the interpretations of the clinical, radiographic, haematological, biochemical, and histopathological findings, the biocompatibility of HA/h-BN/Cs/Ct1 biocomposite materials has been revealed