RESUMO
OBJECTIVE: We evaluated the effectiveness of platelet-rich plasma (PRP) on the regeneration of autogenous cancellous bone and marrow grafted in the alveolar cleft. DESIGN: Twenty patients with alveolar clefts were examined; 6 were the control group and received cancellous bone and marrow grafts without PRP, while the remaining 14 comprised the PRP group and received grafts with PRP. Prior to surgery, 50 ml of blood was withdrawn and 5 ml of PRP gel produced through centrifugal separation. The bone graft mixed with PRP was then packed into the alveolar cleft. Postoperative bone density was assessed as the aluminium-equivalent value on occlusal X-ray films in a qualitative analysis. Quantitative evaluation of regenerated bone was made with computed tomography and panoramic radiographs at 1 month, 6 months and 1 year after surgery. RESULTS: Satisfactory bone bridging formation was observed in all patients without any complications. The bone density of the PRP group was lower than that of the control group at 1 week, but the same after 1 month. The added PRP reduced the resorption of regenerated bone postoperatively. CONCLUSION: Autogenous cancellous bone grafting with PRP, which significantly reduces postoperative bone resorption, is a reliable technique for alveolar bone grafting of cleft patients.
Assuntos
Perda do Osso Alveolar/prevenção & controle , Processo Alveolar/anormalidades , Alveoloplastia/métodos , Regeneração Óssea , Transplante Ósseo , Fissura Palatina/complicações , Plasma Rico em Plaquetas , Adolescente , Adulto , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/etiologia , Processo Alveolar/cirurgia , Alveoloplastia/efeitos adversos , Regeneração Óssea/efeitos dos fármacos , Transplante Ósseo/métodos , Criança , Fissura Palatina/cirurgia , Feminino , Humanos , Masculino , Fator de Crescimento Derivado de Plaquetas/farmacologia , Radiografia Panorâmica , Método Simples-Cego , Tomografia Computadorizada por Raios X , Adulto JovemRESUMO
Human bone marrow-derived mesenchymal cells (hBMMCs) originate from cell populations in the bone marrow and are capable of differentiating along multiple mesenchymal lineages. To differentiate hBMMCs into osteoblasts, adipocytes and chondrocytes, dexamethasone has been used as a differentiation reagent. We hypothesized that dexamethasone would augment the responsiveness of BMMCs to other differentiation reagents and not define the lineage. This study investigated the effect of continuous treatment with 100 nM dexamethasone on the differentiation of BMMCs into three different lineages. hBMMCs cultured with continuous dexamethasone treatment (100 nM) exhibited higher mRNA expression levels of osteogenic markers and higher positive rates of colony forming unit assays for osteogenesis compared to hBMMCs treated with dexamethasone only during the differentiation culture. Furthermore, continuous dexamethasone treatment augmented bone formation capability of monkey-derived BMMCs in a bone induction experimental model at an extra skeletal site. In addition, continuously dexamethasone-treated hBMMCs formed larger chondrogenic pellets and expressed SOX9 at higher level than the control BMMCs. Likewise, continuous dexamethasone treatment facilitated adipogenic differentiation based on mRNA level and colony forming unit analysis. To investigate the mechanism of the augmentation of differentiation, further studies on apoptosis were conducted. The studies indicated that dexamethasone selectively induced apoptosis of some populations of hBMMCs which were thought to have poor differentiation capability.