墨鱼骨转化羟基磷灰石制备及细胞相容性

背景：从自然界中寻找骨移植替代材料来充填骨缺损是目前骨组织工程支架是研究的热点。目的：探索墨鱼骨转化羟基磷灰石三维支架及其作为骨组织工程支架材料的可行性。方法：以墨鱼骨为原料,与磷酸氢二铵在特定条件下发生水热反应,利用X射线衍射、傅里叶变换红外光谱、X射线光电子能谱法和扫描电镜分别对水热反应产物进行表征。结果与结论：墨鱼骨水热反应产物为羟基磷灰石。墨鱼骨转化羟基磷灰石保持了良好的文石相结构,将其与MG63细胞体外培养并考察其细胞相容性,证实墨鱼骨转化羟基磷灰石材料对细胞的生长无明显影响且无明显毒性,不影响细胞的正常增殖,可作为新型骨组织工程细胞支架材料。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

骨形态发生蛋白复合支架的体外缓释性能

背景：临床试验证明纳米晶胶原基骨支架材料具有较好的组织相容性、合适的孔隙率及降解性能,但缺乏缓释生长因子的作用,且无成骨诱导性。 目的：将聚乙稀吡咯啉酮与骨形态发生蛋白复合后形成复合颗粒,再修饰纳米晶胶原基骨制备复合支架,观察骨形态发生蛋白的体外缓释效果。 方法：实验分3组,实验组取冻存管2支,每支放入5 mm×5 mm×5 mm 纳米晶胶原基骨1块,滴加聚乙稀吡咯啉酮混匀,-4 ℃冻存过夜,再滴加骨形态发生蛋白溶液,真空抽干后冻存;对照组1取冻存管2支,每支放入5 mm×5 mm×5 mm 纳米晶胶原基骨1块,滴加骨形态发生蛋白溶液,真空抽干后冻存;对照组2取冻存管2支,每支放入5 mm×5 mm×5 mm未脱钙的大鼠松质骨1块,滴加聚乙稀吡咯啉酮混匀,-4 ℃冻存过夜,再滴加骨形态发生蛋白溶液,真空抽干后冻存。观察14 d,采用ELISA法检测3组复合物骨形态发生蛋白的体外释放活性。 结果与结论：观察到14 d时,两对照组骨形态发生蛋白A值趋近于0,而实验组上清液中骨形态发生蛋白仍保持较高的A值,组间比较差异有显著性意义(P < 0.05)。表明经聚乙烯吡咯烷酮修饰后纳米晶胶原基骨支架具有明显缓释骨形态发生蛋白的作用。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

碳纤维-聚乳酸-聚乙二醇复合支架的制备及性能检测

背景：长期实验发现聚乳酸-聚乙二醇支架的力学性能及细胞相容性能较差,因此多数研究向支架中加入其他材料,以提高其生物活性及力学性能。 目的：制备改性碳纤维-聚乳酸-聚乙二醇支架,并检测其性能。 方法：采用溶液潘注/粒子沥滤法制备改性碳纤维-聚乳酸-聚乙二醇复合支架。对比改性碳纤维-聚乳酸-聚乙二醇复合支架与聚乳酸-聚乙二醇支架的超微结构、孔隙率、吸水性、降解率及力学性能。将改性碳纤维-聚乳酸-聚乙二醇复合支架与聚乳酸-聚乙二醇支架分别与SD大鼠成骨细胞共培养,12 h后采用沉淀法检测细胞黏附率;培养1,3,5,7,9 d后,采用 MTT 法检测细胞增殖。 结果与结论：聚乳酸-聚乙二醇支架材料表面孔结构分布均匀,孔径为(404.0±10.5) µm;改性碳纤维-聚乳酸-聚乙二醇支架碳纤维表面见大量纵向沟槽,表面孔结构分布均匀,孔径为(433.0±3.0) µm,两组支架孔径比较差异有显著性意义(P < 0.05)。改性碳纤维-聚乳酸-聚乙二醇支架的孔隙率、吸水性、弹性模量和抗压强度、降解率、细胞黏附率与增殖率均高于聚乳酸-聚乙二醇支架(P < 0.05)。表明改性碳纤维的加入改善了聚乳酸-聚乙二醇复合支架的力学性能及细胞相容性。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

大鼠成骨细胞与壳聚糖/羟基磷灰石复合支架降解产物的生物相容性

背景：人们对壳聚糖/羟基磷灰石复合多孔生物支架在体内的降解过程并非十分清楚,而且有关其降解产物对成骨细胞的影响研究也较少。 目的：分析大鼠成骨细胞与壳聚糖/羟基磷灰石复合多孔生物支架降解产物的生物相容性。 方法：将培养的第2代大鼠成骨细胞分别在壳聚糖/羟基磷灰石复合支架降解产物浸提液和含体积分数10%胎牛血清的DMEM培养液中培养,培养第2,4,6,8,10天分别对两组细胞做MTT细胞计数,采用联合会推荐法测定细胞碱性磷酸酶活性,采用BCA蛋白定量法测定总蛋白。 结果与结论：在壳聚糖/羟基磷灰石复合多孔生物支架降解产物浸提液中培养的大鼠成骨细胞增殖速度、细胞碱性磷酸酶活性、细胞总蛋白合成及碱性磷酸酶与总蛋白的比值明显高于在体积分数为10%胎牛血清DMEM培养液中培养的细胞(P < 0.05)。表明壳聚糖/羟基磷灰石复合多孔生物支架的降解产物不仅可促进大鼠成骨细胞的黏附、生长和增殖,还可增强其骨化功能,具有较好的生物相容性。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

生物活性玻璃与壳聚糖复合的骨修复材料

背景：生物活性玻璃是一种多相复合材料,具有良好的生物活性、骨传导性及生物相容性,但作为骨修复材料仍然存在不能完全降解、机械强度较低等不足。 目的：设计生物活性玻璃/壳聚糖复合材料骨组织工程支架,并检测其理化性能。 方法：将2.0%壳聚糖盐酸溶液与β-甘油磷酸钠以7∶1的体积比混合制备壳聚糖溶液。称取0.5,1.0,1.5 g生物活性玻璃分别加入上述壳聚糖溶液中,使得壳聚糖与生物活性玻璃的质量比为2∶1,1∶1及1∶1.5。将复合材料浸泡于模拟生理体液中7 d进行体外矿化。 结果与结论：扫描电镜见复合支架具有相互贯通的多孔结构,孔隙率最高可达89%,孔径大小合适,为100-  300 µm,生物活性玻璃以针状形式分散在壳聚糖支架之间,均匀排列,被壳聚糖支架充分包裹结合紧密。随生物活性玻璃含量的增加,复合材料的孔隙率逐渐下降,断裂强度逐渐升高,他们之间呈正相关性。X射线衍射图及傅里叶变换红外光谱证实复合支架中的单一材料未发生性质改变,示差扫描量热法分析显示正常体温情况下材料无质量丢失。矿化3 d后材料表面形成的羟基磷灰石逐渐长大为绒毛状,数量也明显增多;矿化7 d后绒毛状的羟基磷灰石长成为针状,数量进一步增多,且众多的矿化物结成球状。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

低温快速成型亲水改性复合人工骨支架的性能测定

背景：低温快速成型技术具有支架成型可控性、保持材料生物学活性和易于实现支架材料的三维多孔立体结构等优势,被迅速用于骨组织工程支架的制备。 目的：采用低温快速成型制备聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石复合支架,并检测其性能。 方法：采用低温快速成型设备分别制备聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石与聚乳酸-乙醇酸/纳米羟基磷灰石复合支架,通过电镜观察支架超微结构,以介质(乙醇)浸泡法测定支架孔隙率,采用电子试验机检测支架力学性能;将两种支架材料分别与大鼠成骨细胞共培养,培养12 h采用沉淀法检测细胞黏附率,培养1,3,5,7,9,12 d采用CCK-8法检测细胞增殖。 结果与结论：两组支架孔径均在理想范围内并具有较高孔隙率,但聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石支架的孔径波动范围大,孔径均值较聚乳酸-乙醇酸/纳米羟基磷灰石支架小且部分有闭塞现象。聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石支架的细胞黏附率及表面细胞增殖活性高于聚乳酸-乙醇酸/纳米羟基磷灰石支架(P < 0.05),力学性能低于聚乳酸-乙醇酸/纳米羟基磷灰石支架(P < 0.05)。表明聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石复合支架具有良好的细胞相容性。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

不同植骨材料及骨质疏松对腰后路椎间植骨成功率的影响

背景：对于骨质疏松性腰椎疾病患者,在实施后路腰椎间融合治疗时受骨密度等因素的影响会降低植骨融合率,但关于不同植骨材料及骨质疏松对后路腰椎间融合的影响,目前尚无全面的报道。目的：分析不同植骨材料及骨质疏松对腰后路椎间植骨成功率的影响。 方法：回顾性分析227例行腰椎后路椎间融合治疗患者的临床资料,按照植骨材料的不同分为自体髂骨组(n=121)和融合器联合自体髂骨组(n=65)、同种异体骨组(n=41),3组中骨质疏松患者分别有20,22,6例,治疗后随访24个月,对比3组植骨融合情况、融合时间、椎间高度变化及内固定失败等不良事件的发生情况。结果与结论：同种异体骨组内固定失败率、植骨融合时间、椎间高度丢失高于自体髂骨组和融合器联合自体髂骨组(P < 0.05),植骨融合率低于自体髂骨组和融合器联合自体髂骨组(P < 0.05),自体髂骨组和融合器联合自体髂骨组各指标比较差异无显著性意义。在骨质疏松患者中,同种异体骨组内固定失败率、植骨融合时间高于自体髂骨组和融合器联合自体松质骨组(P < 0.05),椎间高度丢失及植骨融合率低于自体髂骨组和融合器联合自体髂骨组(P < 0.05);自体髂骨组融合时间短于融合器联合自体髂骨组(P < 0.05),融合率高于融合器联合自体髂骨组(P < 0.05)。表明在后路腰椎椎间融合过程中,使用自体髂骨或融合器联合自体髂骨均可以获得较高的植骨融合率,内固定失败情况较少;对于合并骨质疏松患者,予以自体髂骨块植骨可以获得更好的融合效果。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

以交联透明质酸钠为支架体外构建组织工程软骨

背景：采用组织工程技术再生和重建软骨是目前修复软骨组织缺损效果最好、最有应用前景的方法。 目的：以体外培养的软骨细胞和交联透明质酸钠为支架材料,开发一套体外构建组织工程软骨的完整方案。 方法：分离新西兰兔膝关节软骨细胞,制成细胞悬液滴加于交联透明质酸钠支架上,体外复合培养21 d,提取RNA进行RT-PCR检测,制备冰冻切片进行显微观察和免疫组织化学观察。 结果与结论：软骨细胞接种于交联透明质酸钠支架材料后,可贴附于支架上生长,并且大量细胞聚集成团,在支架材料的纤维间隙中生长或呈单层细胞附着于支架材料纤维。细胞-支架复合物表达软骨组织特异性蛋白聚糖基因和Ⅱ型胶原α1基因,以及软骨组织特异性蛋白Ⅱ型胶原蛋白,可维持软骨细胞表型。表明培养的细胞-支架复合物在体外培养可形成软骨细胞外基质,有望获得组织工程软骨组织。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

骨组织工程支架材料的研究现状与应用前景

背景：目前组织工程骨修复骨缺损在临床应用中较为关键的问题是建立血管网,为新骨的形成提供氧气及营养物质,并为机体提供代谢途径。 目的：综述近年组织工程骨支架材料的特点,并着重介绍复合支架材料的研究现状。 方法：以“骨组织工程,血管化,支架材料,复合支架材料”为中文检索词,以“bone tissue engineering, vascularization,scaffold,composite scaffold”英文检索词,应用计算机在中国期刊全文数据库和PubMed数据库检索2001年1月至2014年1月的相关文章,将所有文章进行初步筛选后,对保留的文章进一步详细分析、归纳并总结。 结果与结论：按照组织工程骨支架材料的来源不同,可将其分为人工合成材料、天然衍生材料和复合支架材料,单一支架材料难以作为最理想的材料修复骨缺损,复合支架材料能在不同程度上弥补单一支架材料的缺陷,因此近年来组织工程支架材料的发展由单一材料发展为复合材料,并呈现人工合成材料与天然材料有机结合的趋势。但复合支架材料在临床应用中仍然有许多尚待解决的问题,主要有控制复合材料比例,使材料降解速率与组织细胞的生长速率相适应,保持复合材料的多孔隙和高机械强度。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

生物降解材料复合成骨因子在骨科应用研究中的进展

背景：生物可降解植入物不仅可重建骨缺损部位,而且随着材料的逐步降解,新生骨组织可完全替代移植材料,填充骨缺损处。目的：总结生物降解材料复合成骨因子在骨科的研究进展。方法：以“可降解材料,成骨因子,细胞活性因子,骨组织工程;Biodegradable materials,factors,cell active factor,bone tissue engineering”为检索词,应用计算机检索PubMed、万方、CNKI数据库2000至2015年的相关文献。结果与结论：生物可降解医用高分子材料可分为天然高分子材料和人工合成可降解材料。天然高分子材料具有良好的生物相容性,但其机械强度较差;人工合成可降解材料械强度较天然高分子材料高,但容易造成局部酸性物质堆积,产生局部炎症反应。将生物可降解医用高分子材料与成骨因子复合,可提高材料的力学强度与骨诱导能力,但将其作为骨修复材料应用于临床还有很多问题需要解决。  中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

Adipocytic proportion of bone marrow is inversely related to bone formation in osteoporosis

AIMS: Preliminary studies have suggested that there is an increase in adipocytic tissue in osteoporotic (OP) bone, supporting in vitro evidence for a switch in differentiation of stromal cells from the osteoblastic to the adipocytic lineage. To investigate this the variation of the ratio of adipose tissue to haemopoietic/stromal tissue in OP bone was measured. METHODS: The ratio of adipocytic to haemopoietic/stromal tissue (A/H) was measured by semi-automated image analysis in iliac crest biopsies from 127 patients with osteoporosis (84 female patients, 48 male patients; mean age, 55 years; range, 5-80). Fourteen patients with normal histomorphometric data (nine women; five men; mean age, 48 years; range 21-70) acted as controls. RESULTS: The ratio of A/H was higher in OP bone than in the normal controls (OP mean 43.06% v normal mean 22.4%; p < 0.001). Multiple regression analysis showed that 98.5% of the variability in the A/H ratio was the result of age and several measures of bone formation, including cancellous wall thickness, osteoid volume, cancellous thickness, cortical wall thickness, cancellous apposition rate, and bone formation rate, together with cancellous separation (each significant at p < 0.001). Those with the greatest effect on the A/H ratio (in decreasing order) were cancellous apposition rate, osteoid volume, and age. CONCLUSIONS: Cancellous apposition rate, osteoid volume, and age were associated with the increase in the proportion of adipose tissue present in OP bone. Of these, cancellous apposition rate reflects osteoblast activity, indicating that the increase in the volume of adipose tissue in osteoporosis is associated with reduced bone formation, supporting the postulated switch in differentiation of stromal cells from the osteoblastic to the adipocytic pathway in osteoporosis.     

On scaffold designing for bone regeneration: A computational multiscale approach

Scaffold design for bone tissue engineering applications involves many parameters that directly influence the rate of bone tissue regeneration onto its microstructural surface. To improve scaffold functionality, increasing interest is being focused on in vitro and in vivo research in order to obtain the optimal scaffold design for a specific application. However, the evaluation of the effect of each specific scaffold parameter on tissue regeneration using these techniques requires costly protocols and long-term experiments. In this paper, we elucidate the effect of some scaffold parameters on bone tissue regeneration by means of a mathematically based approach. By virtue of in silico experiments, factors such as scaffold stiffness, porosity, resorption kinetics, pore size and pre-seeding are analyzed in a specific bone tissue application found in the literature. The model predicts the in vivo rate of bone formation within the scaffold, the scaffold degradation and the interaction between the implanted scaffold and the surrounding bone. Results show an increasing rate of bone regeneration with increasing scaffold stiffness, scaffold mean pore size and pre-seeding, whereas the collapse of the scaffold occurs for a faster biomaterial resorption kinetics. Requiring further experimental validation, the model can be useful for the assessment of scaffold design and for the analysis of scaffold parameters in tissue regeneration.     

Extravascular albumin in bone tissue.

1. The amount of albumin in extravascular tissue fluid in bone, kidney, intestine, skin and muscle and in plasma of young rabbits has been measured by radial immunodiffusion. 2. The majority of extravascular albumin in kidney, intestine, skin and muscle is exchangeable with plasma albumin, whereas in bone, only the proportion which is in tissue fluid is readily exchangeable; the remaining fraction in calcified matrix is more permanently fixed. 3. About 27% of the albumin in young bone is in tissue fluid, about 57% in calcified matrix and about 16% is intravascular. The total amount of extravascular albumin per unit mass of bone is similar to that found in soft tissues. 4. The volume of intravascular plasma in tissues was determined in two ways: from 51Cr-erythrocyte radioactivity and the venous haematocrit and from the '5 min 125I-fibrinogen space'. 5. The rate of egress of albumin from blood vessels has been estimated from the initial slope of the ratio of extravascular radioactivity in the tissue to plasma radioactivity plotted against time after injection of 125I-albumin. 6. The rate of clearance of the albumin in extravascular tissue fluid in bone is approximately once every hour. This is more rapid than in skin and muscle, comparable with intestine and less rapid than in kidney. 7. The amount of albumin incorporated into calcified matrix of bone per day is calculated to be less than 0-5% of the total albumin passing through the tissue fluid of bone per day.     

骨组织工程支架材料--陶瓷化骨

陶瓷化骨作为骨移植材料 ,得到广泛的研究 ,并已应用于临床。由于其具有天然的骨小梁结构 ,可降解 ,无免疫原性 ,是骨组织工程比较理想的支架材料 ,因此越来越受到重视。本文主要综述陶瓷化骨的理化性质、生物学特性及在骨组织工程中的应用     

骨组织中吡嗪酰胺浓度的高效液相色谱测定

背景：测定结核病化疗药物在病变椎体组织中的生物分布对脊柱结核的治疗具有重要价值。 目的：建立吡嗪酰胺在骨组织中药物浓度的高效液相色谱分析法并测定其在脊柱结核病椎组织中的浓度。 方法：取10例脊柱骨折患者前路椎体次全切除减压的椎骨制备成空白骨匀浆,高效液相色谱法测定吡嗪酰胺骨组织药物浓度。取18例脊柱结核患者(2HRZ/H2R2Z2化疗方案)的病椎硬化骨、亚正常骨、坏死组织以及髂骨为骨组织标本,采用高氯酸蛋白沉淀法获得骨匀浆吡嗪酰胺上清,对方法的专属性、回收率与精密度以及线性范围进行评价。 结果与结论：吡嗪酰胺在265 nm波长下有较大吸收,保留时间7.48 min,无干扰峰出现。在0.048~3.120 μg/g骨匀浆浓度范围内吡嗪酰胺峰面积与骨样本浓度线性关系良好(r=0.999 91),绝对回收率在89.18%~93.75%,方法回收率为96.30%~100.45%,日内、日间精密度分别为4.26%~8.78%和5.12%~9.01%。应用此方法测得吡嗪酰胺在病椎硬化壁为最低抑菌浓度,壁外亚正常骨及对照髂骨达到有效治疗浓度,壁内核心病灶未检测到分布。提示吡嗪酰胺在脊柱结核病椎中存在明显的组织分布差异,硬化壁是其经正常椎体向核心病灶穿透的组织屏障。     

Reduced bone formation in UK Gulf War veterans: a bone histomorphometric study

AIMS: Gulf War veterans report a high prevalence of musculoskeletal symptoms. The aim of this study was to establish whether there were abnormalities in bone turnover and remodelling in a group of symptomatic subjects who had served in the Gulf War. METHODS: Iliac crest bone biopsies were obtained from 17 Gulf War veterans who were seeking litigation and compared with those of 13 age and sex matched healthy controls. Bone histomorphometry was performed using image analysis. RESULTS: Cancellous bone area was significantly lower in Gulf War veterans than in control subjects (p = 0.027) and this was associated with a significantly reduced mineral apposition rate (p = 0.002), mean wall width (p < 0.0001), and bone formation rate at the tissue level (p < 0.0001). CONCLUSIONS: These results demonstrate that in this group of Gulf War veterans there was a significant reduction in bone formation at both the cellular and tissue level and this was associated with a reduction in cancellous bone area. The cause of these abnormalities is unknown but might be related to potentially harmful exposures during service in the Gulf War or to changes in life style as a result of chronic ill health. The clinical relevance of the observed reduction in bone formation remains to be established.     

Effect of embryonic bone tissue on bone regeneration

Fragmented embryonic bone tissue stimulates bone regeneration. Bone formation starts not from implanted embryonic fragments, but in intact periosteum and endosteum containing cambial cells of the osteodifferon. In rabbits, recovery of damaged radial bone after implantation of fragmented embryonic bone tissue into bone defect was associated with a pronounced periosteal reaction and focal resorption of intact ulnar bone. Consolidation of damaged radial bone without implantation of fragmented embryonic bone tissue was incomplete in all experimental animals. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 130 No. 10, pp. 469–474, October, 2000     

功能型骨组织工程支架修复结核性骨缺损

BACKGROUND: Repairing tuberculosis bone defect has become a research focus with the development of anti-tuberculosis functional bone tissue engineering scaffold. OBJECTIVE: To evaluate the preparation, drug release performance and osteogenic properties of the anti-tuberculosis functional bone tissue engineering scaffold. METHODS: PubMed, Chinese Journal Full-text Database, Wanfang databases were searched by computer for articles addressing functional bone tissue engineering scaffold for repair of tuberculosis bone defect. The keywords were “bone tissue engineering scaffold; tuberculosis; bone defect” in English and Chinese. RESULTS AND CONCLUSION: The anti-tuberculosis functional bone tissue engineering scaffold has good drug delivery, biocompatibility, osteogenic properties and anti-tuberculosis properties. As a good choice to avert bone defect relapse, the scaffold enables a long and stable drug release into bone defects to enhance the therapeutic efficacy of anti-tuberculosis drugs topically. Given the technical deficiencies, we can only combine two drugs with the anti-tuberculosis bone tissue engineering scaffold, although the combined use of three or four anti-tuberculosis drugs is preferred. Additionally, a complete course of anti-tuberculosis treatment often lasts for 6-12 months, which cannot be achieved by the existing anti-tuberculosis bone tissue engineering scaffold. Up to now, the effect of this scaffold has not yet been confirmed in animal models, although how to prepare this scaffold has been reported.     

The interface zone of inorganic implantsIn vivo: Titanium implants in bone

The interface zone between titanium implants and bone is considered at the macroscopic, microscopic, and molecular levels. A high rate of successful dental implants of pure titanium is associated with a very close apposition of the bone to the titanium surface, called osseointegration. At the macroscopic level, osseointegration allows efficient stress transfer from the implant to the bone without abrasion or progressive movement that can take place if a fibrous layer intervenes. At the microscopic level, surface roughness and porosity provide interlocking of the implant and bone tissue which grows into direct contact with titanium. Sections studied in the electron microscope show that calcified tissue can be identified within 50 Å of the implant surface. The interface zone includes a tightly adherent titanium oxide layer on the surface of the implant which may be similar to a ceramic material in relation to tissue response. The five year success rate of 90% in 2895 implants in clinical trials since 1965 is associated with the favorable behavior of bone tissue at the interface zone with pure titanium.     

Establishing bone bank at Varazdin General Hospital

AIM: Bone bank has to supply patients of our Department of Orthopedics and patients from Department of Traumatology with necessary bone grafts. METHODS: The paper describes in detail the establishment of Bone bank at Varazdin General Hospital. RESULTS: At Varazdin General Hospital, Department of Transfusion Medicine, in cooperation with Department of Surgery and Department of Orthopedics has been working on developing tissue banking for already 10 years. Primarily, surgical bone remnants and femoral bone heads are collected from live donors and then transplanted. Since 2004, bone tissue has also been collected by means of explantation and then transplanted. In 2004 and 2005, as many as 170 packages of bone tissue were collected at our institution, 40 of which were with spongiosa collected through explantation, and 130 bone remnants. As many as 61 bone remnants and 21 spongiosa were transplanted. Contamination rate of bone grafts was 15.8%. All contamination allografts were destroyed. Bone grafts were used for revision hip arthroplasty, corrective osteotomy and spondylodesis. In the last two years, we have developed a computer program for Bone Bank managing, and have improved our Quality Management System. CONCLUSION: Bone Bank is a service that retrieves, tests, stores and distributes bone grafts and allows a secure system for supplying surgeons and their patients with necessary bone grafts.