多孔钛合金孔径大小对新骨形成的影响

发布时间：2018-06-26 13:11

本文选题：多孔钛合金 + β-磷酸三钙　；参考：《第四军医大学》2012年硕士论文

【摘要】：背景：感染，创伤以及骨肿瘤切除常常导致较大的骨缺损，其修复一直是临床上所面临的难题。金属骨替代材料，如钽金属和钛金属及其合金，具有优良的机械强度，为临床医生所青睐。然而，实体金属材料其弹性模量远高于自然骨，植入体内后容易产生应力遮挡效应，使得植入物松动，脱落，影响植入物的稳定性。资料表明，金属材料的结构特性能明显影响新骨长入的速度，其中多孔材料的孔径大小和孔隙率是极其重要的两个影响因素。对金属植入材料进行多孔设计，不仅保留了金属材料优良的机械强度，耐腐蚀性，还可以通过调整孔径大小和孔隙率来改变材料的弹性模量，使其与自然骨相匹配。研究显示，具有孔隙结构的植入材料能促进营养物质和代谢产物的运输，促进细胞的黏附，引导新骨的长入，因此，多孔金属骨植入物材料越来越多地被应用于临床，已达到良好的材料-骨界面生物稳定和骨修复重建的作用。以往的研究多针对小孔径多孔材料（＜1.0mm），大孔径多孔材料对新骨形成的影响研究尚不充分，是否多孔金属材料的孔径越大，骨长入的效果越好，多大的孔径参数对骨长入最为有利，上述问题成为本研究的重点。实验一多孔钛合金孔径大小对新骨形成的影响目的：观察不同孔径的大孔多孔钛合金植入骨缺损区后新骨长入情况，评价骨缺损的修复重建效果方法：通过电子束熔融（EBM）技术制备1.0mm，2.0mm，3.0mm三种不同孔径，孔径规则，孔隙率依次为73%，79%，86%的多孔钛合金材料，规格为1.0cm×1.0cm×1.0cm正方体。取18只家犬，随机分为1.0mm，2.0mm，3.0mm孔径材料组，每组6只。制备双侧股骨外侧髁缺损模型，缺损区域大小同材料大小，随后植入各孔径组材料，分别于术后4周，8周，12周行大体标本观察，X线片，组织形态检测，Micro-CT扫描，观察三组不同孔径材料与周围骨的整合情况及孔隙中的新骨长入情况。结果：组织学观察发现，1.0mm孔径组材料随时间延长孔径中心及材料周围新生骨明显增多；2.0mm孔径组材料8周和4周相比新生骨面积比显著增加，12周与8周相比无明显增多；3.0mm孔径材料组随时间延长新生骨面积比增加不明显。术后12周，大体标本观察和X线片观察显示三组材料均与周围骨紧密连接，其中1.0mm孔径组材料中心成骨明显，2.0mm孔径组和3.0mm孔径组材料中心多为纤维组织充斥。组织学观察显示，12周时1.0mm孔径组材料周围被骨质紧密包绕，孔中有较多新生骨形成，且孔壁四周有大量纤维母细胞和软骨细胞形成，新骨面积百分比为20.11%±2.74%；2.0mm孔径组和3.0mm孔径组材料周围虽然有骨质包绕，但中心空洞，骨质形成较少，新骨面积百分比分别为10.45%±1.83%，9.26%±1.00%。1.0mm孔径组材料在各时间点新生骨面积百分比均明显高于其余两组，P0.01,差异具有统计学意义。2.0mm孔径组和3.0mm孔径组材料相比，P0.05，无显著统计学差异。Micro-CT扫描结果显示，12周时1.0mm孔径组材料中心新生骨较多，骨密度明显高于其余两组，材料周围亦有骨质紧密包绕。2.0mm和3.0mm孔径组材料周围虽有骨质包绕，但中心空洞，基本无骨质形成。结果与组织学结果相符。结论：多孔钛合金材料的骨长入受材料孔径大小的影响，对于大孔结构，孔径超出一定范围将影响新骨长入；对材料孔径进行适当的设计将更有利于材料的骨传导作用。实验二不同孔径多孔钛合金/β-磷酸三钙复合材料修复骨缺损的实验研究目的：评价不同孔径多孔钛合金/β-磷酸三钙复合材料对犬长骨骨缺损修复的影响。方法：采用电子束熔融（EBM）技术制备两种不同孔径（孔径分别为2.0mm，3.0mm）的多孔钛合金材料，孔径规则，，规格为1.0cm×1.0cm×1.0cm正方体，将其孔隙用β-磷酸三钙（β-TCP）烧结填充。取8只成年家犬，随机分为两组，每组4只。制备家犬双侧股骨外侧髁缺损模型，缺损区域大小同材料大小，将两种孔径的复合材料分别植入股骨外侧髁缺损区，左侧为2.0mm组，右侧为3.0mm组。3个月后取材，行大体观察，X线观察，组织学观察了解两种孔径的复合材料与周围骨的整合情况及新骨长入情况。结果： X线片显示3个月时两组多孔复合材料均与周围骨连接，都有不同程度的成骨，成骨由周围向中心生长。组织学观察显示3个月时2.0mm孔径组材料与周围骨连接尚存在间隙，骨小梁排列稀疏。3.0mm孔径组材料周围及中心有大量新生骨组织形成，骨小梁排列紧密，数量明显多于2.0mm孔径组材料，周围骨与材料结合紧密。2.0mm孔径组材料的新骨面积百分比（14.65%1.12%）明显少于3.0mm孔径组（25.95%1.11%），两组差异有统计学意义，P0.01。结论：多孔钛合金/β-磷酸三钙复合材料的孔径大小影响新骨的长入；人工骨与多孔钛合金材料复合后将改变原有孔径单纯多孔金属材料的骨长入行为。
[Abstract]:Background:
Infection, trauma, and bone tumor resection often lead to large bone defects, and their repair has been a clinical problem. Metal bone substitute materials such as tantalum metal and titanium metal and their alloys have excellent mechanical strength and are favored by clinicians. However, the elastic modulus of solid metal materials is much higher than that of the natural bone and is implanted in the body. It is easy to produce the stress shielding effect, which makes the implants loose, exfoliated, and affects the stability of the implants. Data show that the structural properties of metal materials can significantly affect the speed of the new bone, in which the pore size and porosity of the porous material are two important factors. The porous design for metal implants is not only retained. The excellent mechanical strength and corrosion resistance of metal materials can also be adjusted by adjusting the size and porosity of the pores to match the elastic modulus of the material to match the natural bone. The study shows that the porous material can promote the transport of nutrients and metabolites, promote cell adhesion, and guide the growth of new bone, therefore, Porous metal implant materials have been used more and more in clinical practice and have achieved good material - bone interface biological stability and bone repair and reconstruction. Previous studies have focused on small pore porous materials (< 1.0mm). The effect of large aperture porous materials on the formation of new bone is not sufficient, and the larger the pore size of porous metal is, The better the effect of bone ingrowth, the larger the pore size parameters are most favorable for bone ingrowth.
Effect of pore size on the formation of new bone in porous titanium alloy
Objective:
To observe the growth of new bone after implantation of macroporous porous titanium alloy with different diameters and evaluate the effect of bone defect reconstruction.
Method:
Through electron beam melting (EBM) technique, three kinds of porous titanium alloy materials with different pore sizes and pore sizes of 73%, 79% and 86% were prepared by electron beam melting (EBM). The specifications were 1.0cm x 1.0cm x 1.0cm square. 18 dogs were selected to be randomly divided into 1.0mm, 2.0mm, 3.0mm aperture material group, 6 of each group, and the defect area was prepared by bilateral femoral lateral condyle defect. The size of the area was the same as the size of the material, then the materials were implanted in each aperture group. The gross specimens were observed at 4 weeks, 8 weeks and 12 weeks after the operation. The X-ray film, tissue morphology and Micro-CT scan were used to observe the integration of the three groups of different pore sizes and the surrounding bone and the condition of the new bone in the pores.
Result:
Histological observation showed that the size of the 1.0mm pore group increased significantly with time and the new bone around the material increased significantly over time, and the ratio of new bone area in the 2.0mm aperture group was significantly increased in 8 weeks and 4 weeks, and there was no significant increase in the 12 weeks compared with 8 weeks. The specimen observation and X-ray observation showed that the three groups were closely connected with the surrounding bone, of which the 1.0mm aperture group material center was osteogenic, and the 2.0mm aperture group and the 3.0mm aperture group were mostly fibrous tissue. The histological observation showed that at the time of 12 weeks, the pores of the 1.0mm pore group were tightly wrapped around the bone, and there were more new bone formation in the hole. A large number of fibroblasts and chondrocytes were formed around the wall of the hole, the percentage of the new bone area was 20.11% + 2.74%, while the 2.0mm aperture group and the 3.0mm aperture group were surrounded by bone, but the central cavity, the bone formation was less, the percentage of the new bone area was 10.45% + 1.83%, and the 9.26% + 1.00%.1.0mm pore group materials were new bone at all time points. The percentage of area was significantly higher than that of the other two groups, P0.01. The difference was statistically significant between the.2.0mm aperture group and the 3.0mm pore group. There was no significant difference in P0.05. The results of.Micro-CT scan showed that there were more new bone in the material center of the 1.0mm aperture group and the bone density was significantly higher than the other two groups at the 12 week, and the bone around the material also had bone tightly wrapped around the material. The.2.0mm and 3.0mm pore size groups had bone wrapping around the material, but there was no bone formation in the center cavity. The results were consistent with histological findings.
Conclusion:
The bone length of the porous titanium alloy material is influenced by the size of the material. For the large pore structure, the pore size beyond a certain range will affect the growth of the new bone, and the proper design of the pore size will be more beneficial to the bone conduction of the material.
Experimental two porous titanium alloy / beta tricalcium phosphate composite materials with different pore sizes to repair bone defects
Objective:
Objective to evaluate the effect of porous titanium alloy / beta tricalcium phosphate composite material on the repair of long bone defects in dogs.
Method:
Two porous titanium alloy materials with different apertures (2.0mm, 3.0mm) were prepared by electron beam melting (EBM). The pore size was 1.0cm x 1.0cm x 1.0cm square, and the pores were filled with beta tricalcium phosphate (beta -TCP). The 8 adult dogs were randomly divided into two groups, each group was 4. The damage model, the size of the defect area and the size of the material, two kinds of pore diameter composite materials were implanted into the lateral condyle defect area of the femur respectively. The left side was 2.0mm group and the right side was 3.0mm group.3 months later. General observation, X-ray observation, and histological observation were made to understand the integration of the two kinds of pore size composite and the surrounding bone.
Result:
The X - ray showed that the two groups of porous composite materials were all connected to the surrounding bone at 3 months. There were different degrees of osteogenesis and bone formation from the periphery to the center. The histological observation showed that there was a gap between the 2.0mm aperture group and the surrounding bone at 3 months, and the bone trabeculae arranged around the sparse.3.0mm aperture group and the center had a large number of new bone tissue. As a result, the bone trabecula was closely arranged, and the number was obviously more than that of the 2.0mm aperture group. The percentage of the new bone area (14.65%1.12%) of the surrounding bone and the material combined with the tight.2.0mm aperture group (14.65%1.12%) was significantly less than that of the 3.0mm pore group (25.95%1.11%). The difference was statistically significant, P0.01. conclusion:
The pore size of porous titanium alloy / beta tricalcium phosphate composite material affects the growth of the new bone, and the combination of artificial bone and porous titanium alloy will change the bone growth behavior of the original porous metal material.
【学位授予单位】：第四军医大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R318.08

【参考文献】