Use of buccal fat pad-derived stem cells cultured on bioceramics for repair of critical-sized mandibular defects in healthy and osteoporotic rats

Objective To compare new bone formation in mandibular symphysis critical-sized bone defects (CSBDs) in healthy and osteoporotic rats filled with bioceramics (BCs) with or without buccal fat pad mesenchymal stem cells (BFPSCs). Materials and methods Thirty-two adult female Sprague–Dawley rats were randomized to two groups ( n = 16 per group): group 1 healthy and group 2 osteoporotic (with bilateral ovariectomy). The central portion of the rat mandibular symphysis was used as a physiological CSBD. In each group, eight defects were filled with BC (hydroxyapatite 60% and β-tricalcium phosphate 40%) alone and eight with BFPSCs cultured on BC. The animals were sacrificed at 4 and 8 weeks, and the mandibles were processed for micro-computed tomography to analyze radiological union and bone mineral density (BMD); histological analysis of the bone union; and immunohistochemical analysis, which included immunoreactivity of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2). Results In both groups, CSBDs filled with BC + BFPSCs showed greater radiological bone union, BMD and histological bone union, and more VEGF and BMP-2 positivity, compared with CSBDs treated with BC alone at 4 and 8 weeks. Conclusions The application of BFPSCs cultured on BCs improves bone regeneration in CSBDs compared with BCs alone in healthy and osteoporotic rats. Clinical relevance Our results may aid bone regeneration of maxillofacial CSBDs of both healthy and osteoporotic patients, but further studies are necessary.