The Study Of Barrier Memberance Combinating With Autogenous Bone Marrow Stromal Cells And Platelet-rich Plasma On Alveolar Bone Defect In Dogs

Objective: The development of implants that are predictable and successful long-term replacements for missing teeth in both full and partially edentulous situations has led to their acceptance as part of mainstream restorative dental therapy. However, loss of teeth always results in bone resorption and loss of interdental papillae, and the quality and quantity of bone are the basic factors in treatment planning and determine the type of implant to be used. The resorption and bone defects limit the application of dental implant. Guided Bone Regeneration (GBR) using membrane is a good technique to restore local bone defects. The new method sufficiently utilizes the potential ability in organis by means of placing barrier membrane. Osteoblast and cell factors play an important role in restoration of bone tissue. Bone marrow stromal cells(BMSCs) were cultured in vivo and the osteoblast-like phenotypes of the cells were investigated in our experiment. Platelet-rich plasma(PRP) is comprised of various growth factor. The study evaluates the bone formation of Bio-Gide bilayer bioresorbable collagen membrane when used alone or in combination with BMSc or PRP in dog alveolar bone defects. The study has included two parts.Methods: (1)The BMSCs were obtained from mongrel dogs and cultured and subcultured. The proliferation and osteogenic differentiation of BMSCs were observed. (2) Three male mongrel dogs were used. The first and second premolars were extracted from the bilateral maxillary and mandibular bone and four alveolar intrabone defects(8mm in height, 5mm in width,15mm in length) were created. The surgically-created defects were randomly assigned to one of the treatments: (A) control (nothing was used), (B) GBR(only Bio-Gide), (C) GBR+ BMSCs (Bio-Gide+ BMSCs) (D) GBR+ PRP (Bio-Gide+PRP). The dogs were sacrificed at 4, 8, and 16 weeks after the surgery.The macroscopic,radiographic and histological processing were performed.Results: (1)The cultured BMSCs comprised a single phenotypic population and displayed a fibroblast-like morphology. Without induction condition, cells changed from spindle-shape to cuboidal and polygonal in cell morphology. With 3 passages process of extensive subcultivation, Alkaline phosphatase (ALP) express and deposition of calcium salt were observed in the culture. (2) The amount of newly formed bone was significantly greater in the groups using the membrane than in the control group within 8 weeks. However, there were no apparent differences between the use of the collagen barrier membrane alone or in combination with BMSCs or PRP in enhancing new bone formation.Conclusion : (1)The proliferation and osteogenic differentiation of the BMSCs were observed. The cell can be used as an ideal cell in therapy of bone defect. The lower expression of ALP suggests the BMSCs in our culture system are mainly undifferentiated osteoprogenitors. (2) The results of this study indicate that GBR treatment with collagen membranes may significantly enhance bone regeneration within 8 weeks. The influence of GBR technique in combination with BMSCs or PRP in accelerating the repair of alveolar bone defects is not clear.