Objective <p>The aim of this study is to evaluate the osseointegration and osteogenesis to determine bone formation, using the potential of composite samples that consist of hydroxyapatite (HA), high density polyethylene (HDPE) and multiwalled carbon nanotubes (MWCNTs) at a specific ratio that is implanted in the connective tissue of animal models.</p> Methods <p>In this study, several biocomposite samples were created and examined using in vivo evaluation to determine the biocompatibility and osteogenesis of the implantation utilising radiographical tests (X-rays) and histological tests.</p> Results <p>X-ray and histological tests demonstrated successful results in some samples as in good material integration with the tissues, and active cellular response of bone formation indicating faster osteogenesis.</p> Future Work <p>This study seeks to develop a new method for manufacturing samples that are more suitable for tissue engineering applications like 3D bioprinting to optimize scaffold design, and implanting the samples in more animal models for a longer period then evaluating with a broader range of tests to ensure ideal outcomes.</p> Lay Summary <p>In this study, MWCNTs were investigated for their effects on the microstructure, phase analysis, morphology, and thermal and mechanical properties of biocomposite materials (HA, HDPE). In order to evaluate the effectiveness of biocomposite scaffolds (HA/HDPE/MWCNTs) in bone healing, rabbit femur defects were used as models. Based on the results of the study, hot pressing and hybrid composite materials are appropriate for the growth of bone tissue at the indicated percentages. As compared to the control group, the treatment sample had greater bone density and less mature and adipose cells, whereas the control group had better bone structure and healing.</p>