骨形成蛋白-2基因促进犬牙周组织再生的体内研究

目的：观察重组人骨形成蛋白-2（rhBMP-2）质粒对犬牙周骨缺损再生作用的影响.方法：选用6只成年beagle犬,将其下颌两侧的第2、3、4前磨牙（P2、P3、P4）作为实验牙.在每颗实验牙的近中根颊侧制作＂U＂型骨缺损,并随机设计为3组,即pIRES-rhBMP-2组、rhBMP-2组（阳性对照组）和PBS组（空白对照组）.术后第4与第8周分别处死动物.光镜下观察组织学变化,采用Image-Pro-Express系统测量新生牙槽骨和牙骨质的高度、新生结缔组织的附着量.测量结果以SAS 6.12软件包进行Newman-Keulsq检验.结果：实验第8周时,组织学观察可见2个实验组新生牙槽骨接近于正常骨结构,新生牙周纤维稠密,富含血管;空白对照组胶原纤维稀疏,排列不规则.新生组织测量结果显示：2个实验组新生牙槽骨和牙骨质的高度、新生结缔组织的附着量较空白对照组显著增加（P＜0.05,P＜0.01）;但2个实验组间相比无显著性差异（P＞0.05）.结论：pIRES-rhBMP-2有较强的骨诱导活性,能有效促进犬牙周骨缺损的组织再生.     

胶原-羟基磷灰石人工骨与胶原膜引导牙周组织再生的动物实验研究

目的：将胶原-羟基磷灰石人工骨与胶原膜联合应用于修复牙周缺损的动物实验,探讨其用于引导牙周组织再生的可行性。方法：人工构建4只成年Beagle犬下颌后牙区牙周缺损模型,分别随机采用：胶原-羟基磷灰石人工骨/胶原膜、胶原-羟基磷灰石人工骨、空白对照治疗,每组8颗牙,12周后处死动物,进行组织学观察并测量新生组织高度。结果：与单纯植入胶原-羟基磷灰石人工骨组相比,胶原-羟基磷灰石人工骨/胶原膜组获得了更多的新附着,表现为有较多的新生牙槽骨、新生牙周膜和新生牙骨质样组织生长,2组之间新生组织差异有显著性（P〈0.05）。结论：胶原-羟基磷灰石人工骨与胶原膜联合运用修复牙周牙槽骨缺损引导牙周组织再生的效果优于单纯植入人工骨。     

钛芯多孔羟基磷灰石-骨形成蛋白复合物对受体细胞免疫功能的影响

目的：探讨钛芯多孔羟基磷灰石-骨形成蛋白(HA—BMP)复合物对受体细胞免疫功能的影响。方法：通过建立实验动物肌袋模型，植入不同植体材料，以流式细胞仪检测植入后受体的T淋巴细胞CD4^ ,D8^ 的动态变化，并于肉眼及光镜下观察植体埋植后周围组织的变化。结果：钛芯多孔HA—BMP复合物组埋植后外周血CD4^ ／CD8^ T淋巴细胞比例较正常对照组显著增高，随后呈时间依赖性下降，到第4周恢复正常，与异体牙埋植组有显著差异，但与假手术组、自体牙组及HA埋植组无明显差异。结论：钛芯多孔HA—BMP复合物免疫原性低，对受体细胞免疫无明显影响。     

引导牙周组织再生术与联合羟基磷灰石植入在牙周手术治疗中的应用

比较引导牙周组织再生术,相对于联合骨替代材料—羟基磷灰石植入,二者在临床疗效的优缺点。     

重组人骨形成蛋白-2及其在牙周组织工程中的运用

重组人骨形成蛋白-2(rhBMP-2)是牙周组织再生的分子调节器,它调节牙周膜细胞的迁移、分化,对它的研究可加速牙周组织工程的发展。研究表明,rhBMP-2无论在动物体内或体外均能明显诱导牙槽骨等牙周组织的形成。本文简述了rhBMP-2的分子结构、作用的分子机制以及其在牙周组织工程研究中的运用。     

骨形成蛋白促进牙周组织再生的动物实验研究

目的将骨形成蛋白（ｂｏｎｅｍｏｒｐｈｏｇｅｎｅｔｉｃｐｒｏｔｅｉｎ，ＢＭＰ）联合应用于牙周引导组织再生（ｇｕｉｄｅｄｔｉｓｓｕｅｒｅｇｅｎｅｒａｔｉｏｎ，ＧＴＲ）技术中，观察和比较其对牙周组织再生修复的影响和意义。方法制备狗下颌后牙区人工骨缺损，于清创后分组置入引导膜材料和ＢＭＰ，以常规翻瓣术为对照；分不同时期取材做组织学观察和评价。结果实验组较对照组新生组织量多，而以复合ＢＭＰ组效果最为显著；膜材料在早期有一定抑制结合上皮根向迁移的作用。结论利用外源性ＢＭＰ的主动生物诱导活性，可望应用于临床促进牙周硬组织成分的新生修复。     

重组人骨形成蛋自-2及真在牙周组织工程中的运用

重组人骨形成蛋白-2(rhBMP-2)是牙周组织再生的分子调节器,它调节牙周膜细胞的迁移、分化,对它的研究可加速牙周组织工程的发展.研究表明,rhBMP-2无论在动物体内或体外均能明显诱导牙糟骨等牙周组织的形成.本文简述了rhBMP-2的分子结构、作用的分子机制以及其在牙周组织工程研究中的运用.     

个体化钛支架复合珊瑚羟基磷灰石和重组人骨形成蛋白2修复兔下颌骨缺损

目的通过观察个体化钛支架复合珊瑚羟基磷灰石(CHA)和重组人骨形成蛋白2(rhBMP-2)修复兔下颌骨缺损的实验效果,探讨下颌骨个体化修复再生的途径。方法以9只新西兰大白兔为实验对象,采用磨骨术建立兔下颌骨单侧缺损模型,利用计算机辅助设计/制作、快速成型技术等设计制作兔下颌骨个体化钛修复体,再将其与CHA和rhBMP-2复合应用于兔下颌骨标准化缺损修复,通过大体标本观察、骨密度检测、生物力学测试和组织学染色对下颌骨缺损的个体化再生修复效果进行研究。结果兔下颌骨解剖形态恢复理想,生物力学测试、骨密度检测及组织学观察均显示随时间点延长成骨效果呈明显上升趋势(P<0.05),钛支架内具有大量新骨形成,新生骨组织在24周时已明显成熟。结论采用快速成型技术制作的个体化钛支架复合CHA和rhBMP-2,可望通过骨再生途径实现下颌骨缺损的个体化修复重建。     

复合膜引导牙周组织再生

目的：观察基因重组人骨形成蛋白-2、胶原、聚乳酸／聚羟基乙酸共聚体（rhBMP-2／Co／PLGA）复合膜引导牙周组织再生的效果。方法：在杂犬的第四前磨牙及第-磨牙颊侧部位,制备急性牙周组织缺损模型,将复合膜材料植入实验部位,设对侧为同体对照。术后8周处死动物,切取双侧下颌骨标本,行软x线照相和组织学观察。结果：实验侧可见大量新生牙槽骨、牙骨质和牙周膜纤维形成;对照侧主要是牙龈上皮和上皮下结缔组织增生。结论：rhBMP-2／Co／PLGA复合膜符合GTR的要求,能够引导牙周组织再生。     

骨形态蛋白复合物联合引导组织再生技术修复牙周骨缺损的实验研究

目的评价骨形态蛋白复合物联合引导组织再生技术修复牙周骨缺损的效果。方法选择6只新西兰兔，制备下前牙牙周骨缺损模型，将其分为3组：GTR组(牙周骨缺损处植入胶原膜)、BMP组(牙周骨缺损处植入骨形态蛋白复合物和胶原膜)和OFD组(牙周骨缺损处未植入任何物，对照组)。术后12周分别观察各组缺损处的组织学变化。结果BMP组骨缺损处只见少量的软组织，新生骨组织的量及其成熟程度明显优于GTR组和OFD组，显示骨组织修复良好。结论骨形态蛋白复合物联合GTR技术修复牙周骨缺损，与传统的GTR术和牙周翻瓣术相比，更能有效促进牙周骨组织再生与修复。     

Accelerated Bone Formation in Distracted Alveolar Bone After Injection of Recombinant Human Bone Morphogenetic Protein‐2

Background: This study evaluates the effect of recombinant human bone morphogenetic protein‐2 (rhBMP‐2) on the quality and quantity of regenerated bone when injected into distracted alveolar bone. Methods: Sixteen adult beagle dogs were assigned to either the control or rhBMP‐2 group. After distraction was completed, an rhBMP‐2 dose of 330 μg in 0.33 mL was injected slowly into the distracted alveolar crest of the mesial, middle, and distal parts of the alveolar bone in the experimental group. Histologic and microcomputed tomography analyses of regenerated bone were done after 2 and 6 weeks of consolidation. Results: After 6 weeks of consolidation, the vertical defect height in the middle of the regenerated bone was significantly lower in the rhBMP‐2 group (2.2 mm) than in the control group (3.4 mm) (P <0.05). Additionally, the width of the regenerated bone was significantly greater in the rhBMP‐2 group (4.3 mm) than in the control group (2.8 mm) (P <0.05). The bone density and volume of regenerated bone in the rhBMP‐2 group were greater than in the control group after 6 weeks of consolidation (P <0.001). Conclusion: Injection of rhBMP‐2 into regenerated bone after a distraction osteogenesis procedure significantly increased bone volume in the dentoalveolar distraction site and improved both the width and height of the alveolar ridge and increased the bone density.     

骨形成蛋白2基因转染的人牙周膜成纤维细胞的骨诱导作用

目的　建立表达骨形成蛋白2 (BMP-2)的人牙周膜成纤维细胞(HPDLFs),观察其体内成骨作用,为牙周缺损修复基因疗法的建立提供实验依据。方法　采用脂质体载体将人BMP-2噬菌粒表达载体pBK-B2转染至 HPDLFs。利用免疫组化ABC法检测转染细胞内BMP-2蛋白的表达,并于无菌条件下将转染细胞注射于裸鼠股部肌肉内,21 d后取材,苏木精-伊红染色观察肌肉组织内骨形成情况。结果　BMP-2基因转染后HPDLFs内有BMP- 2蛋白的表达。在注射BMP-2基因转染细胞的肌肉组织内可见明显的新骨形成。结论　BMP-2基因成功转入HP- DLFs中并得到有效表达,转染BMP-2基因的HPDLFs能够在体内诱导新骨形成。     

双抗胶原膜引导牙周组织再生的实验性研究

目的 :观察双抗胶原膜 (BACM)引导周组织再生的疗效。方法 :在狗下颌牙P2———P4区建立急性牙周缺损模型 ,放置BACM于缺损区域 ,行引导牙周组织再生术。以常规翻瓣术为对照。结果 :实验组再生牙周组织量显著多于对照组。结论 :BACM引导牙周组织再生效果切实可靠     

Effect of Recombinant Human Bone Morphogenetic Protein 2 Associated With a Variety of Bone Substitutes on Vertical Guided Bone Regeneration in Rabbit Calvarium

Background: A major challenge for dental implantology is to consistently obtain appropriate bone augmentation before implant placement. The aim of this study is to evaluate the effect of recombinant human bone morphogenetic protein 2 (rhBMP‐2) associated with bone substitute materials beta‐tricalcium phosphate (β‐TCP), biphasic calcium phosphate (BCP), and bovine bone mineral on vertical guided bone regeneration (GBR) in rabbit calvarium. Methods: Four titanium cylinders were fixed to the calvarium of 22 rabbits. In group 1 (n = 10), three cylinders were randomly filled with one of the test materials, and one cylinder was filled with a blood clot (CL). In group 2 (n = 12), the cylinders were randomly assigned to the same materials and CL but with the addition of rhBMP‐2. Bone labels were injected over the course of 13 weeks, and euthanasia was performed 14 weeks after surgery in both groups. Results: The mean volume and area of tissue growth was greater in group 2 (with rhBMP‐2) than in group 1 (without rhBMP‐2), irrespective of the material used (P <0.001). The mean volume of tissue growth in the CL cylinder was smaller than that observed with all other materials (P <0.001) in both groups. The mean area of regenerated bone in the CL cylinder was smaller than that observed in the β‐TCP cylinder (P = 0.028). The histologic study revealed more lamellar bone in the rhBMP‐2 group, with a greater level of biodegradation of all the bone substitute materials tested. Conclusion: The use of rhBMP‐2/absorbable collagen sponge (ACS) combined with all of the bone substitute materials tested resulted in a greater amount of bone formation than that produced with the bone substitute materials alone or rhBMP‐2/(ACS) and CL using the rabbit calvarium GBR model.     

Doxycycline Counteracts Bone Morphogenic Protein 2–Induced Osteogenic Mediators

Background: Microbial colonization during wound healing may exaggerate the inflammatory response and could adversely affect the outcome of periodontal regeneration. Bone morphogenic proteins (BMPs) directly augment bone regeneration. Interestingly, inhibitors of tissue collagenases, such as sub‐antimicrobial–dose doxycycline, also indirectly promote hard‐tissue regeneration. In this study, it is hypothesized that BMP2‐mediated bone regeneration would be positively affected by simultaneous treatment of sub‐antimicrobial–dose doxycycline. Methods: Human periodontal ligament (PDL) cells were stimulated with: 1) 10 ng/mL BMP2; 2) 1 μg/mL doxycycline; or 3) a combination of the two. The expressions of alkaline phosphatase, osteocalcin, osteonectin, and osteopontin were analyzed along with in vitro mineralized nodule formation and calcium accumulation. Results: BMP2 was a potent inducer of osteocalcin/osteopontin (statistically significant at P <0.01) and osteonectin in PDL cells relative to stimulation with doxycycline. However, doxycycline relative to BMP2 (statistically significant at P <0.001) upregulated the expression of alkaline phosphatase and in vitro mineralized nodule formation. Contrary to expected results, combined BMP2 and doxycycline induced a statistically significant (P <0.001) downregulation of alkaline phosphatase, osteocalcin, osteonectin/osteopontin, and in vitro mineralized nodule formation compared to stimulation with either BMP2 or doxycycline alone. Conclusions: Combined treatment of BMP2 and doxycycline in PDL cells counteracts the osteogenic mediators. Molecular interaction of growth factors should be explored before using a combination of these biologic molecules. It is important and clinically relevant to determine whether tetracycline and its other derivatives also counteract BMP functions. Animal models should be used to confirm these in vitro results.     

重组人骨形成蛋白2对人牙周膜成纤维细胞的生物学作用

目的:研究重组人骨形成蛋白2 (rhBMP2) 对人牙周膜成纤维细胞(HPDLFs) 的生物学作用。方法:原代培养HPDLFs ,并观察rhBMP2 对HPDLFs 增殖、碱性磷酸酶(ALP) 活性、骨钙素(OC) 合成及矿化结节形成的作用。结果:0125～2 mgPml rhBMP2 对HPDLFs 的增殖无明显作用,015～2 mgPml rhBMP2 显著提高HPDLFs 的ALP 活性,刺激OC合成和矿化结节形成。结论:rhBMP2 对HPDLFs 的作用具有剂量依赖性。rhBMP2 能够刺激HPDLFs 表达成骨细胞表型并促进其表型成熟。     

Bone Regeneration of Rat Calvarial Defect by Magnesium Calcium Phosphate Gelatin Scaffolds with or without Bone Morphogenetic Protein-2

Regeneration of large bone losses has been achieved with limited success due to either donor site complications in autogenous bone graft or lack of an ideal biomaterial in the case of allografts. Magnesium calcium phosphate-gelatin sponges were prepared with different concentrations of MCP; namely 0, 50 and 90 wt%. Eight mm defects were drilled in the calvaria of 48 male Fischer 344 rats. MCP-gelatin scaffolds containing or without bone morphogenetic protein were placed at the defect site. Animals were sacrificed at 3 and 12 weeks, post-operatively, with evaluation of bone regeneration by using micro CT and histological examinations. Results showed that the combination of BMP-2 and gelatin sponges could provide a slow release system that significantly enhanced bone regeneration at both 3 and 12 weeks in comparison with the non BMP-2-containing 90 wt% MCP-gelatin sponges. The combination of 50 wt% MCP-gelatin sponges and BMP-2 showed significant bone formation at 3 weeks in comparison with the non BMP-2 containing gelatin sponges, indicating that the addition of MCP to the gelatin scaffold had a synergistic advantage in combination with BMP-2. This novel scaffold has shown adequate porosity to allow cell growth, amenability for sterilization, biocompatibility and biodegradability with the ability to provide a slow release system for BMP-2 to enhance bone regeneration.