BACKGROUND Critically sized bone defects represent a significant challenge to orthopaedic surgeons worldwide.These defects generally result from severe trauma or resection of a whole large tumour.Autologous bone graft...BACKGROUND Critically sized bone defects represent a significant challenge to orthopaedic surgeons worldwide.These defects generally result from severe trauma or resection of a whole large tumour.Autologous bone grafts are the current gold standard for the reconstruction of such defects.However,due to increased patient morbidity and the need for a second operative site,other lines of treatment should be introduced.To find alternative unconventional therapies to manage such defects,bone tissue engineering using a combination of suitable bioactive factors,cells,and biocompatible scaffolds offers a promising new approach for bone regeneration.AIM To evaluate the healing capacity of platelet-rich fibrin(PRF)membranes seeded with allogeneic mesenchymal bone marrow-derived stem cells(BMSCs)on critically sized mandibular defects in a rat model.METHODS Sixty-three Sprague Dawley rats were subjected to bilateral bone defects of critical size in the mandibles created by a 5-mm diameter trephine bur.Rats were allocated to three equal groups of 21 rats each.Group I bone defects were irrigated with normal saline and designed as negative controls.Defects of group II were grafted with PRF membranes and served as positive controls,while defects of group III were grafted with PRF membranes seeded with allogeneic BMSCs.Seven rats from each group were killed at 1,2 and 4 wk.The mandibles were dissected and prepared for routine haematoxylin and eosin(HE)staining,Masson's trichrome staining and CD68 immunohistochemical staining.RESULTS Four weeks postoperatively,the percentage area of newly formed bone was significantly higher in group III(0.88±0.02)than in groups I(0.02±0.00)and II(0.60±0.02).The amount of granulation tissue formation was lower in group III(0.12±0.02)than in groups I(0.20±0.02)and II(0.40±0.02).The number of inflammatory cells was lower in group III(0.29±0.03)than in groups I(4.82±0.08)and II(3.09±0.07).CONCLUSION Bone regenerative quality of critically sized mandibular bone defects in rats was better promo展开更多
Recently, porous titanium granules （PTGs） have been indicated for the preservation of the dimensions of post-extraction sockets, as a filler in sinus lift procedures and for the treatment of peri-implant and periodo...Recently, porous titanium granules （PTGs） have been indicated for the preservation of the dimensions of post-extraction sockets, as a filler in sinus lift procedures and for the treatment of peri-implant and periodontal defects, based on the osteoconductivity and dimensional stability of the titanium granules. However, there is a lack of information regarding the use of this material in larger defects and in conjunction with membranes. The objective of this study is to test the behavior of PTGs used to fill critical size defects in rabbit tibiae, with and without membranes. Critical defects were created in both tibiae of rabbits, divided randomly into three groups： Group A （defect filled with PTG）, Group B （defect filled with PTG＋collagen membrane） and a control group （empty defect）. After six weeks, histomorphometric analysis was performed. The results showed more defect closures at the cortical area （87.37%±2.2%） and more bone formation at the marrow area （57.6%± 1.3%） in Group B, in comparison with the other groups （P〈0.05）; the use of membranes improved the material stability expressed as more percentages of the original material when membranes were used （P〈0.05）. Finally, inflammatory reactions were observed when the granules were not protected by membranes. In spite of the limitations of this animal study, it may be concluded that PTG particles are osteoconductive and allow bone growth. The PTG particles must be covered by a membrane, especially when grafting larger defects, in order to control particle migration, promote clot stabilization and separate the PTG graft from undesired soft tissue cells.展开更多
目的通过影像学及组织学观察,评价内固定对带蒂筋膜瓣稳定性影响及其促超临界骨缺损(exceedcritical size defect,ECSD)成骨作用,为临床应用提供理论依据。方法取32只4～5月龄新西兰大白兔右侧尺骨制备长1 cm的骨-骨膜ECSD模型,随机分为...目的通过影像学及组织学观察,评价内固定对带蒂筋膜瓣稳定性影响及其促超临界骨缺损(exceedcritical size defect,ECSD)成骨作用,为临床应用提供理论依据。方法取32只4～5月龄新西兰大白兔右侧尺骨制备长1 cm的骨-骨膜ECSD模型,随机分为A、B组,每组16只。A组将自体红骨髓(autologous red bone marrow,ARBM)接种于含BMP的骨诱导活性材料上制备组织工程骨,植入骨缺损区,在邻近骨缺损区制备一带蒂深筋膜瓣将其包裹作为对照组;B组在A组基础上行微型钛板内固定作为实验组。术后2、4、6、8周分别行X线片检查、大体观察及组织学观察,并对植入的组织工程骨骨再生修复情况行影像学4分评分法和组织学修复区内骨形态计量分析。结果实验动物均存活至实验完成。X线片示,从组织工程骨的骨纹理、骨断端间隙、材料吸收降解的影像学变化,以及新骨再生、骨干结构形成、髓腔再通方面,B组均优于A组;术后各时间点B组X线片评分均大于A组,差异有统计学意义(P<0.05)。大体及组织学观察示,从筋膜瓣的稳定性、组织工程骨吸收替代速度、外骨痂形成、新生软骨细胞与成熟骨细胞数量和分布,以及新生骨小梁构建、成熟板层骨形成和骨髓腔相通等成骨现象,B组均优于A组;术后各时间点B组新生骨小梁面积占修复区面积比值均大于A组,差异有统计学意义(P<0.05)。结论加强内固定后膜结构及骨缺损区的稳定性均提高,与单纯带蒂筋膜瓣促ECSD成骨作用相比,具有加快组织工程骨再生新骨速度、缩短骨缺损修复时间、提高成骨质量等优点。展开更多
文摘BACKGROUND Critically sized bone defects represent a significant challenge to orthopaedic surgeons worldwide.These defects generally result from severe trauma or resection of a whole large tumour.Autologous bone grafts are the current gold standard for the reconstruction of such defects.However,due to increased patient morbidity and the need for a second operative site,other lines of treatment should be introduced.To find alternative unconventional therapies to manage such defects,bone tissue engineering using a combination of suitable bioactive factors,cells,and biocompatible scaffolds offers a promising new approach for bone regeneration.AIM To evaluate the healing capacity of platelet-rich fibrin(PRF)membranes seeded with allogeneic mesenchymal bone marrow-derived stem cells(BMSCs)on critically sized mandibular defects in a rat model.METHODS Sixty-three Sprague Dawley rats were subjected to bilateral bone defects of critical size in the mandibles created by a 5-mm diameter trephine bur.Rats were allocated to three equal groups of 21 rats each.Group I bone defects were irrigated with normal saline and designed as negative controls.Defects of group II were grafted with PRF membranes and served as positive controls,while defects of group III were grafted with PRF membranes seeded with allogeneic BMSCs.Seven rats from each group were killed at 1,2 and 4 wk.The mandibles were dissected and prepared for routine haematoxylin and eosin(HE)staining,Masson's trichrome staining and CD68 immunohistochemical staining.RESULTS Four weeks postoperatively,the percentage area of newly formed bone was significantly higher in group III(0.88±0.02)than in groups I(0.02±0.00)and II(0.60±0.02).The amount of granulation tissue formation was lower in group III(0.12±0.02)than in groups I(0.20±0.02)and II(0.40±0.02).The number of inflammatory cells was lower in group III(0.29±0.03)than in groups I(4.82±0.08)and II(3.09±0.07).CONCLUSION Bone regenerative quality of critically sized mandibular bone defects in rats was better promo
文摘Recently, porous titanium granules （PTGs） have been indicated for the preservation of the dimensions of post-extraction sockets, as a filler in sinus lift procedures and for the treatment of peri-implant and periodontal defects, based on the osteoconductivity and dimensional stability of the titanium granules. However, there is a lack of information regarding the use of this material in larger defects and in conjunction with membranes. The objective of this study is to test the behavior of PTGs used to fill critical size defects in rabbit tibiae, with and without membranes. Critical defects were created in both tibiae of rabbits, divided randomly into three groups： Group A （defect filled with PTG）, Group B （defect filled with PTG＋collagen membrane） and a control group （empty defect）. After six weeks, histomorphometric analysis was performed. The results showed more defect closures at the cortical area （87.37%±2.2%） and more bone formation at the marrow area （57.6%± 1.3%） in Group B, in comparison with the other groups （P〈0.05）; the use of membranes improved the material stability expressed as more percentages of the original material when membranes were used （P〈0.05）. Finally, inflammatory reactions were observed when the granules were not protected by membranes. In spite of the limitations of this animal study, it may be concluded that PTG particles are osteoconductive and allow bone growth. The PTG particles must be covered by a membrane, especially when grafting larger defects, in order to control particle migration, promote clot stabilization and separate the PTG graft from undesired soft tissue cells.
文摘目的通过影像学及组织学观察,评价内固定对带蒂筋膜瓣稳定性影响及其促超临界骨缺损(exceedcritical size defect,ECSD)成骨作用,为临床应用提供理论依据。方法取32只4～5月龄新西兰大白兔右侧尺骨制备长1 cm的骨-骨膜ECSD模型,随机分为A、B组,每组16只。A组将自体红骨髓(autologous red bone marrow,ARBM)接种于含BMP的骨诱导活性材料上制备组织工程骨,植入骨缺损区,在邻近骨缺损区制备一带蒂深筋膜瓣将其包裹作为对照组;B组在A组基础上行微型钛板内固定作为实验组。术后2、4、6、8周分别行X线片检查、大体观察及组织学观察,并对植入的组织工程骨骨再生修复情况行影像学4分评分法和组织学修复区内骨形态计量分析。结果实验动物均存活至实验完成。X线片示,从组织工程骨的骨纹理、骨断端间隙、材料吸收降解的影像学变化,以及新骨再生、骨干结构形成、髓腔再通方面,B组均优于A组;术后各时间点B组X线片评分均大于A组,差异有统计学意义(P<0.05)。大体及组织学观察示,从筋膜瓣的稳定性、组织工程骨吸收替代速度、外骨痂形成、新生软骨细胞与成熟骨细胞数量和分布,以及新生骨小梁构建、成熟板层骨形成和骨髓腔相通等成骨现象,B组均优于A组;术后各时间点B组新生骨小梁面积占修复区面积比值均大于A组,差异有统计学意义(P<0.05)。结论加强内固定后膜结构及骨缺损区的稳定性均提高,与单纯带蒂筋膜瓣促ECSD成骨作用相比,具有加快组织工程骨再生新骨速度、缩短骨缺损修复时间、提高成骨质量等优点。
