Volume: 57 Issue: 3
Year: 2026, Page: 443-452, Doi: https://doi.org/10.51966/jvas.2026.57.3.443-452
Received: June 13, 2026 Accepted: Sept. 2, 2026 Published: Sept. 30, 2026
Critical-sized bone defects remain a major challenge in orthopaedic reconstruction because they lack the intrinsic capacity for complete regeneration, while many synthetic grafts fail to achieve optimal bioactivity, biodegradation, and host integration. This study evaluated the regenerative efficacy of a novel magnesium phosphate–triphasic silica coated hydroxyapatite composite (MP–HASi) compared with conventional magnesium phosphate cement (MPC) in a rat femoral defect model. Bilateral unicortical femoral defects (2 × 6 mm) were surgically created in twenty-one adult male Wistar rats, with MPC implanted in the left femur (control) and MP–HASi in the right femur (test). Animals were euthanised at 2, 6, and 12 weeks for evaluation using serial radiography, gross morphology, histopathology, semiquantitative histomorphometry, and scanning electron microscopy. MP–HASi demonstrated earlier radiographic mineralisation from week 2, enhanced woven bone formation, accelerated cortical bridging, and more rapid graft–host integration than MPC. Histological and histomorphometric analyses revealed significantly reduced inflammatory and fibrotic responses, greater new bone formation, earlier maturation from woven to lamellar bone, and superior defect remodelling in the MP–HASi group throughout the study. By week 12, MP–HASi-treated defects exhibited complete lamellar bone reconstruction with complete biomaterial resorption, whereas MPC-treated defects retained residual graft material and showed incomplete remodelling. Scanning electron microscopy further confirmed intimate bone–material contact, abundant osteocyte lacunae, seamless interfacial integration, and synchronised biodegradation in the MP–HASi group. These findings demonstrate that MP–HASi provides superior osteoconductive and osteointegrative performance with coordinated resorption and bone remodelling, highlighting its potential as a next-generation synthetic bone graft substitute for the treatment of critical-sized osseous defects and supporting further evaluation in large-animal and translational preclinical models.
Keywords: Bone regeneration, magnesium phosphate cement, hydroxyapatite composite, osteointegration.
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© 2026 Dinesh et al. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Sankar, S. N, Dinesh, P. T., Fernandez, F. B., Kumar, N. S. J., Remya, V., Pradeep, M., Hamza, P., & Varma, H. (2026). A next-generation Magnesium Phosphate composite exhibits superior biointegration and remodelling compared to conventional MPC in rat femoral defects. Journal of Veterinary and Animal Sciences, 57(3), 443-452