To study the effect of two composition ratios of nano-hydroxyapatite and collagen(NHAC)composites on repairing alveolar bone defect of dogs.Eighteen healthy adult dogs were randomly divided into three groups.Two kinds of the NHAC composites were prepared according to the constituent ratios of 3:7 and 5:5;immediately after extraction of the mandibular second premolars,each kind of the NHAC composite was implanted into extraction socket,respectively:Group I,nHA/Col紏3:7;Group II,nHA/Col紏5:5 and Group III,blank control group.The bone-repairing ability of the two grafts was separately analyzed by morphometric measurement,X-ray tomography examination and biomechanical analysis at 1st,3rd and 6th month post-surgical,respectively.The NHAC composites were absorbed gradually after implanting into alveolar bone defect and were replaced by new bone.The ratios of new bone formation of Group I was significantly higher than that of Group II after 3 months(P<0.05).The structure and bioactive performance can be improved when the ratio between the collagen and the hydroxyapatite was reasonable,and the repairing ability and effect in extraction sockets are obviously better.
Yan-FuWangCheng-Yue WangPengWanShao-GangWangXiu-Mei Wang
In this article,the biodegradation process and bone formation of a mineralized collagen reconstruction rod embedding in necrosis of human femoral head were investigated by imageological and histological methods.Computed radiography(CR)computerized tomography(CT),common pathological section and hard tissue section analysis were used to evaluated the dynamics of imageological and histopathological changes of femoral head,interface between the host bone and implant and the bone reconstruction process.The results showed that the density of rods increased closed to that of host bones after 1 year implanting,and the interface between them turns to blurring.Hard tissue grinding sections analysis showed osteocytes appearing in sparse bone trabecular and bone pit region,as well as a few vessels in the degraded dye powder matrix were noticed,indicating the new bone forming between the implants and host bones.Regular decalcified sections analysis showed scattered osteoclasts,multinucleated giant cells and fibrosis components existing in the degraded rod and the host bone trabecular.Degraded debris was endocytosed by giant cells,and vascular network formed around the boundaries of the implanted rod.The good osteointegration has been expressed by the interface between the implanted rod and the host bone becoming blurred.Histological results indicated that the implanted rod degradation process and new bones regeneration simultaneously occurred around the boundaries of embedding rod.New bone and host bone were hinged and co-existed.
Baogang XieHao WangJianhua HaoPing WangNa ZhangJingjing WuZhiye QiuFuzhai Cui
目的通过与跗骨窦入路对比,评价"八"字切口入路治疗跟骨骨折的效果。方法回顾性分析54例跟骨骨折病人的临床资料。按手术入路不同将病人分为跗骨窦组和"八"字组,比较两组手术时间、术中出血量、术后48 h视觉模拟评分法(VAS)评分、末次随访时的AOFAS踝-后足评分系统评分(AOFAS评分)和Maryland评分、手术前后的Bohler角和Gissane角。结果跗骨窦组和"八"字组病人分别获得了(17.9±3.4)和(19.2±6.3)个月的随访。两组间手术时间、术中出血量、术后48 h VAS评分、末次随访时的AOFAS评分和Maryland评分、术后Bohler角和Gissane角等比较差异均无显著性(P>0.05)。两组病人术后Bohler角和Gissane角与术前相比差异均有统计学意义(t=9.84~13.70,P<0.01)。结论"八"字切口入路与跗骨窦入路具有相同的手术疗效,但前者具有更广阔的视野及操作空间,可以避免术中不必要的软组织挤压,可作为首选方案应用于SandersⅡ、Ⅲ型跟骨骨折的治疗。
A clear understanding on cell migration behaviors contributes to designing novel biomaterials in tissue engineering and elucidating related tissue regeneration processes. Many traditional evaluation methods on cell migration including scratch assay and transwell migration assay possess all kinds of limitations.In this study, a novel honeycomb cell assay kit was designed and made of photosensitive resin by 3D printing. This kit has seven hexagonal culture chambers so that it can evaluate the horizontal cell migration behavior in response to six surrounding environments simultaneously, eliminating the effect of gravity on cells. Here this cell assay kit was successfully applied to evaluate endothelial cell migration cultured on self-assembling peptide （SAP） RADA （AcN-RADARADARADARADA-CONH2） nanofiber hydrogel toward different functionalized SAP hydrogels. Our results indicated that the functionalized RADA hydrogels with different concentration of bioactive motifs of KLT or PRG could induce cell migration in a dose-dependent manner. The total number and migration distance of endothelial cells on functionalized SAP hydrogels significantly increased with increasing concentration of bioactive motif PRG or KLT. Therefore, the honeycomb cell assay kit provides a simple, efficient and convenient tool to investigate cell migration behavior in response to multi-environments simultaneously.
At the time of implanting bone-related implants into human body,a variety of biological responses to the material surface occur with respect to surface chemistry and physical state.The commonly used biomaterials(e.g.titanium and its alloy,Co–Cr alloy,stainless steel,polyetheretherketone,ultra-high molecular weight polyethylene and various calcium phosphates)have many drawbacks such as lack of biocompatibility and improper mechanical properties.As surface modification is very promising technology to overcome such problems,a variety of surface modification techniques have been being investigated.This review paper covers recent advances in surface modification techniques of bone-related materials including physicochemical coating,radiation grafting,plasma surface engineering,ion beam processing and surface patterning techniques.The contents are organized with different types of techniques to applicable materials,and typical examples are also described.
