Bone regeneration in critical-sized mandibular symphysis defects using bioceramics with or without bone marrow mesenchymal stem cells in healthy, diabetic, osteoporotic, and diabetic-osteoporotic rats.

OBJECTIVES: To compare new bone formation in mandibular critical-sized bone defects (CSBDs) in healthy, diabetic, osteoporotic, and diabetic-osteoporotic rats filled with bioceramics (BCs) with or without bone marrow mesenchymal stem cells (BMSCs). METHODS: A total of 64 adult female Sprague-Dawley rats were randomized into four groups (n = 16 per group): Group 1 healthy, Group 2 diabetic, Group 3 osteoporotic, and Group 4 diabetic-osteoporotic rats. Streptozotocin was used to induce type 1 diabetes in Group 2 and 4, while bilateral ovariectomy was used to induce osteoporosis in Group 3 and 4. The central portion of the rat mandibular symphysis was used as a physiological CSBD. In each group, eight defects were filled with BC (hydroxypatatite 60% and ß-tricalcium phosphate 40%) alone and eight with BMSCs 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 all groups (healthy, diabetics, osteoporotics, and diabetics-osteoporotics), the CSBDs filled with BC + BMSCs showed greater radiological bone union, BMD, histological bone union, and more VEGF and BMP-2 positivity, in comparison with CSBDs treated with BC alone (at 4 and 8 weeks). CONCLUSIONS: Application of BMSCs cultured on BCs improves bone regeneration in CSBDs compared with application of BCs alone in healthy, diabetic, osteoporotic, and diabetic-osteoporotic rats.

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 ß-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.

Bone union formation in the rat mandibular symphysis using hydroxyapatite with or without simvastatin: effects on healthy, diabetic, and osteoporotic rats.

OBJECTIVE: The objective is to compare new bone formation in critical defects in healthy, diabetic, and osteoporotic rats filled with hydroxyapatite (HA) alone and HA combined with simvastatin (SV). MATERIALS AND METHODS: A total of 48 adult female Sprague-Dawley rats were randomized into three groups (n = 16 per group): Group, 1 healthy; Group 2, diabetics; and Group 3, osteoporotics. Streptozotocin was used to induce type 1 diabetes in Group 2, while bilateral ovariectomy was used to induce osteoporosis in Group 3. The central portion of the rat mandibular symphysis was used as a physiological critical bone defect. In each group, eight defects were filled with HA alone and eight with HA combined with SV. 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 all groups (healthy, diabetics, and osteoporotics), the defects filled with HA + SV presented greater radiological bone union, BMD, histological bone union, and more VEGF and BMP-2 positivity, in comparison with bone defects treated with HA alone. CONCLUSIONS: Combined application of HA and SV improves bone regeneration in mandibular critical bone defects compared with application of HA alone in healthy, diabetic, and osteoporotic rats. CLINICAL RELEVANCE: This study might help to patients with osteoporosis or uncontrolled diabetes type 1, but future studies should be done.