纳米级羟基磷灰石梯度涂层植入体骨结合的研究

目的 研究纳米级羟基磷灰石梯度涂层植入体的骨结合情况。方法在Beagle犬股骨髁植入纳米级羟基磷灰石梯度涂层栓、普通级羟基磷灰石栓和钛合金（Ti-6AL-4V）栓,4、8和12周比较植入体-骨界面的组织学、骨动力学参数并进行电镜观察。结果纳米级羟基磷灰石梯度涂层组的降解速度慢于普通级羟基磷灰石组,骨动力学参数和成骨细胞形态均优于对照组。结论纳米级羟基磷灰石梯度涂层植入体优于普通级羟基磷灰石涂层植入体。     

纳米级羟基磷灰石梯度涂层植入体的生物反应

目的 :研究纳米级羟基磷灰石梯度涂层植入体的骨结合和界面细胞因子的表达。方法 :在Beagle犬股骨髁植入纳米级羟基磷灰石梯度涂层栓和钛合金 (Ti 6AL 4V )栓 ,在 4、 8、 12周比较植入体 -骨界面的组织学和TNF α、IL 1β、IL 6、IL 10的表达。结果 :植入体 -骨界面能快速的达到骨性结合 ,TNF α、IL 1β、IL 6表达水平较低 ,IL 10水平明显高于钛合金组。结论 :纳米级羟基磷灰石梯度涂层材料有临床应用前景。     

金属与羟基磷灰石微孔表面股骨植入体与骨结合强度的比较研究

目的比较金属与羟基磷灰石(hydroxyapatite,HA)微孔表面股骨植入体与骨的结合强度.方法用等离子喷涂技术,分别喷涂HA微粒和钴铬钼合金微粒于不锈钢三棱针表面,配对植入15只成年家兔的股骨,饲养2个月作拔出试验,并比较手术当日与2个月后的X线改变.结果HA与钴铬钼合金涂层三棱针平均剪切强度分别为(0.98±0.12)MPa和(0.65±0.15)MPa,二者有显著性差异(P＜0.05).X线片HA涂层三棱针周围有较多的成骨反应,透明区较金属涂层三棱针要少而窄.结论植入兔的股骨短时间内,HA微孔表面植入体较金属微孔表面植入体更为稳定.     

纳米级羟基磷灰石生物陶瓷涂层研究进展

纳米级羟基磷灰石生物陶瓷涂层颗粒大小限于纳米水平,使得材料的内在缺陷减少.材料表面抗剥脱和抗降解能力均优于微米级羟基磷灰石材料,同时力学和生物学方面有很大提高,在组织工程、假体涂层和抗肿瘤研究中也显示出广阔的应用前景,可望成为下一代骨科材料.     

等梯度羟基磷灰石涂层植入体的实验研究

目的：观察一种新的等梯度羟基磷灰石（ＨＡ）涂层结构的骨－ＨＡ界面的生物力学及生理学特征。方法：应用经皮质骨植入体模式，在１２条狗的双侧股骨上共植入９６个ＨＡ表面涂层及非涂层钛合金栓。分别于术后６、１２及１８周处死后取材。测定界面抗剪强度并作组织学观察。结果：在要诟任一时间段涂层植入体界面抗剪强度均显著高于非涂层者。涂层植入人体表面成骨活跃，骨与涂层结合紧密，而非涂层植入体表面与骨组织间有纤维组织存     

钛-羟基磷灰石功能梯度材料骨结合强度的初步研究

目的从力学角度研究钛-羟基磷灰石功能梯度材料与骨组织的结合强度。方法将钛-羟基磷灰石功能梯度材料植入8只新西兰大耳白兔颅骨中,用同样规格的纯钛和纯羟基磷灰石作为对照。术后进行临床及X-ray观察、剪切强度及骨结合强度的测定。结果钛-羟基磷灰石功能梯度材料与骨结合界面的剪切强度均强于各个时期纯钛与骨结合界面的剪切强度(P<0.05),在8周后强于纯羟基磷灰石与骨结合界面的剪切强度(0.01相似文献   

钛-羟基磷灰石功能梯度材料骨结合强度的初步研究

目的从力学角度研究钛-羟基磷灰石功能梯度材料与骨组织的结合强度.方法将钛-羟基磷灰石功能梯度材料植入8只新西兰大耳白兔颅骨中,用同样规格的纯钛和纯羟基磷灰石作为对照.术后进行临床及X-ray观察、剪切强度及骨结合强度的测定.结果钛-羟基磷灰石功能梯度材料与骨结合界面的剪切强度均强于各个时期纯钛与骨结合界面的剪切强度(P＜0.05),在8周后强于纯羟基磷灰石与骨结合界面的剪切强度(0.01＜P＜0.05).结论钛-羟基磷灰石功能梯度材料具有良好的界面结合强度的特性,此材料可能具有较好的应用前景.     

纳米级羟基磷灰石骨科材料研究进展

纳米级羟基磷灰石材料人工制备技术已经成熟．复合材料能模拟自然骨结构．增加成骨细胞的贴附、增殖和矿化,并有肿瘤细胞杀伤作用．有望成为下一代骨科材料。     

羟基磷灰石梯度涂层的生物学研究

目的：本实验研究HA梯度涂层材料在体内负重条件下的生物学表现,方法：将经梯度涂层羟基磷灰石的钛合金栓与非涂层钛合金栓分别植入狗下肢的负重区,观察植入体与骨结合界面的生物学特性,结果：组织学研究显示类骨样基质直接沉积在HA涂层表面,涂层与宿主骨紧密结合。而非涂层组新生骨形成的数量和速度远低于HA涂层组,生物力学测试显示HA组与宿主骨结合界面的抗剪强度均远大于非涂层组（P＜0．01）,结论：结果表明HA梯度涂层法作为新颖的层方法有其实际临床应用价值。     

复合型纳米羟基磷灰石人工骨研究进展

羟基磷灰石人工骨具有良好的生物相容性和生物活性,其缺点是脆性较大及骨诱导性较弱.与纳米羟基磷灰石复合的有机高分子材料具有生物相容性和可降解性,复合后能相互补强,从而可提高人工骨的强度和韧性,有效修复骨缺损;纳米羟基磷灰石和天然高分子材料复合后可达到松质骨的强度;骨生长因子加入复合人工骨,缓释后持续诱导骨生成,使复合人工骨获得骨诱导性能;纳米双相生物陶瓷的降解性能较纳米羟基磷灰石好,多孔隙纳米双相陶瓷人工骨有骨传导性和成骨性.理想的人工骨不是拘泥于对骨组织结构和成分的简单模仿,而是要构建符合生物学特性的多孔隙、高强度骨细胞爬行支架.     

羟基磷灰石涂层人工股骨柄的实验研究

本实验以国产ＨＡ涂层烧结的犬用人工股骨柄为研究对象，将行关节置换后的２０只成年犬，按术后３、６、１２、２４、４０周平均分成５个组，全面观察ＨＡ涂层在体内的性能和在负重情况下对假体的固定效果。综合运用了普通光镜、偏振光显微镜、扫描电镜、荧光显微镜来进行组织学观察，发现术后各期ＨＡ涂层都无明显降解，ＨＡ周围无炎性细胞，ＨＡ涂层与钛基底的结合基本良好，ＨＡ外都有骨组织与之紧密结合，并且ＨＡ表面的成骨多集中在股骨的前侧、内侧。ＨＡ表面的部分区域被纤维组织覆盖，且多见于股骨的后侧、外侧。组织计量分析示：术后各期ＨＡ表面骨及纤维膜的占有率分别在６６．４４％～７８％及１６．２２％～１８．５８％之间。影像学示：所有术侧股骨都未见异位骨化、骨皮质反应、骨外膜反应和骨反应线，假体周围都未见透亮线（１例ＨＡ层有碎裂的假体除外）。所有假体周围都有不同程度的皮质骨下新生骨形成。力学测试示：假体上、中、下３段的剪切强度随植入时间的增加而增大，最大剪切强度为３３．０９ＭＰａ，最小剪切强度为０．２８ＭＰａ。本实验表明，用国产ＨＡ涂层来固定人工股骨柄是切实可行的。     

羟基磷灰石涂层人工颈椎间盘的实验研究

目的 观察新型人工颈椎间盘假体置入犬颈后能否维持颈椎生理曲度和椎间隙度, 能否保持适度的活动能力及假体与骨的初期和长期稳定性。方法 参照对１５条犬颈椎的几何测量,设计新型犬用基磷灰石（ｈｙｄｒｏｘｙａｐａｔｉｔｅ,ＨＡ）涂层人工Ｃ６－７间盘假体。２０条成年犬随机分为３、６、１２周ＨＡ涂层组及６周无涂层组。行Ｘ线摄片、组织学观察、生物力学及力学推出试验、组织形态计量学测定。结果 Ｘ线显示术后各组犬颈     

Osteointegration of hydroxyapatite-coated stems of femoral prostheses

Summary Twenty-two fully hydroxyapatite-coated femoral implants were retrieved during autopsy. These components, provided with a bipolar femoral head, had been inserted for a displaced fracture of the femoral neck. The time of implantation varied from 5 days to 76 months. Osteointegration of the implant was evident, without any formation of fibrous tissue: grossly 40% of the perimeter of the prosthesis at the level of its proximal third was interfaced with bone (60% at the mid third and 70% at the distal third). Remodeling of bone had ensued. Deposition of bone was most prominent in the calcar zone, along the medial and lateral sides and around the tip. Cell-mediated reabsorption of the coating was routinely present in these bone remodeling areas. The remnants of the coating were particularly thin in the upper area (10 µm) while it appeared nearly intact in the distal part of the component (141 µm). Formation of new bone was often coupled with absorption. No debris of the coating was found in the joint tissues or in the bearing surface of the polyethylene insert. These overall histopathological features confirm the mechanical stability of the implant and active remodeling of bone, as well as focal removal of the HA coating associated with osteoclastic activity. No side-effects of coating degradation could be demonstrated.     

双梯度羟基磷灰石涂层复合rhBMP-2研究

目的 :检验双梯度生物活性涂层假体材料的生物学特性 ;检测rhBMP 2对HA涂层与骨界面之间生物连接的影响。方法 :将同一规格的 3种不同植入体 (Ti、Hati、rhBmp 2HaTi)植入狗股骨 ,术后 3、6、16周分别处死三组动物 ,通过X线照片、不脱钙带植入体的组织切片、计算机图像分析、顶出试验、扫描电镜等检查手段进行观察。结果 :早期骨 -假体界面骨性结合率比较 :Ti 相似文献   

Effects of Strontium on the Physicochemical Characteristics of Hydroxyapatite

In a previous experimental study using a chronic renal failure rat model, a dose-related multiphasic effect of strontium (Sr) on bone formation was found that could be reproduced in an in vitro set-up using primary rat osteoblasts. The results from the latter study allowed us to distinguish between a reduced nodule formation in the presence of an intact mineralization at low Sr-doses (1 g/ml) and an interference of the element with the hydroxyapatite (HA) formation at high doses (20–100 g/ml). To further investigate the latter effect of Sr on physicochemical bone mineral properties, an in vitro study was set up in which the UMR-106 rat osteosarcoma cell line was exposed to Sr, added to the cell culture medium in a concentration range varying between 0–100 g/ml. Temporal growth and functionality of the culture was investigated by measurement of the alkaline phosphatase activity and calcium (Ca) concentration in the culture medium (used as an index of Ca-incorporation, i.e., HA formation) at various time points. At the end of the culture period (14 days post-confluence), samples of the mineralized cultures were taken for further analysis using X-ray diffraction (XRD) and Fourier Transform Infra-Red Spectroscopy (FTIR). Synthetic HA doped with various Sr concentrations (based on the cell culture and previous experimental studies and yielding Sr/(Sr+Ca) ratios ranging from 0–60%), was prepared and examined for crystal growth and solubility. Crystal size was assessed using scanning electron microscopy (SEM). Ca incorporation indicated a reduced mineralization in the 20 and 100 g/ml Sr groups vs. controls. Sr-doped synthetic HA showed a significant dose-dependent reduction in crystal growth, as assessed by SEM, and an increase in solubility, apparent from 12.7% Sr/(Sr+Ca) on. Moreover, in both mineralized cultures and synthetic HA, XRD and FTIR analysis showed a reduced crystallinity and altered crystal lattice at similar concentrations. These new data support our previous in vivo and in vitro findings and point to a potential physicochemical interference of Sr with HA formation and crystal properties in vivo.     

Hydroxyapatite porous coating and the osteointegration of the total hip replacement

Introduction The main purpose of this study is to evaluate the efficacy of the plasma sprayed, combined porous titanium alloy/HA coating in promoting bony ingrowth and mechanical stabilization of total hip implants. The performance of the titanium alloy/HA type coated hip prostheses and the one of the same shape but without any coating, is compared in this paper. Material and methods The implants were manufactured from titanium alloy VT-6 (ASTM F-136). The hip stems utilized in the control group were identical to those subsequently coated. The coating consists of a plasma deposited first layer of porous titanium alloy (TiAl₆V₄), similar in composition to the forged substrate and a plasma deposited second layer of oversprayed hydroxyapatite, Ca₁₀ (PO₄)₆ (OH) ₂. Coating is located in the critical area of the hip stems, where high fixation interface strength is desired, i.e. in the proximal area of the stem where the highest stresses occur. The porous titanium alloy/hydroxyapatite (HA) coated femoral stems were implanted in 50 patients. The results were compared with a control group of 50 patients with the same type of endoprosthesis, but without the porous titanium alloy/HA coating. Both groups of patients were operated on and evaluated by the same orthopedic surgeons with a mean follow up of 11.4 years in the HA group and 10.6 years in the control group. Results HHS in the control group was preoperatively 35.5 points (range 26–49) and 85.1 points (range 54–100) in the time of the last control. HHS in the HA group was preoperatively 34.1 points (range 27–56) and 94.4 points (range 89–100) in the time of the last control. In 28 cases (56%) of the control group a range of translucencies were obvious. These translucent lines, however, did not appear with any of the patients in the coated implant group except one infection stem migration. Conclusion Experience with the HA-type coated hip implants demonstrates substantially higher degree and quality of osteointegration in the porous titanium alloy/HA type implants.     

成人成骨细胞与多孔羟基磷灰石联合培养观察

目的：观察成人成骨细胞与多孔羟基磷灰石（hydroxypatite,HA)的相容性及细胞在HA上的生长情况。方法：来自成人骨髓的成骨细胞与多孔HA联合培养,倒置显微镜、扫描电镜观察细胞生长情况。结果：成人成骨细胞与多孔HA有良好的相容性,细胞在HA微孔表面生长良好。结论：以HA为载体,可望制成有生物活性的人工骨。