种植体磷酸钙溶胶表涂与早期骨整合研究

目的探讨磷酸钙(CaP)溶胶涂层能否传导并增强多孔型钛合金(Ti6Al4V)种植体表层的早期骨整合(即骨性愈合)。方法将制备有极薄的CaP溶胶表面涂层的多孔型钛合金种植体作为实验组,将未经CaP涂层的种植体作为对照组,分别植入16只兔的胫骨中。种植区愈合2周后,取含种植体的骨组织标本,利用反向扫描电镜摄像技术和Bioquant图像分析系统进行形态观测研究。结果在多孔型钛合金种植体表面,CaP涂层组所测量出的绝对骨接触长度(ACL:1.18mm)、接触长度分数比(CLF:40.4%)、骨生长直线距离(SLBG:1.19mm)各数据均高于对照组种植体(分别为0.74mm,27.0%,1.04mm),两组差异有统计学意义(P<0.01)。结论多孔型种植体CaP溶胶涂层能有效传导并增强骨组织长入,形成骨与种植体界面的广泛骨整合。     

磷酸钙骨水泥的研究进展综述

磷酸钙骨水泥的研究进展综述林立波曾维权骨缺损的修复重建是骨科的一个重要课题。虽然新鲜自体骨是修复重建的一种有效材料，但因供骨来源有限，且增加手术创伤，使其临床应用受到很大限制。寻求合适的骨替代材料用于骨缺损的生物性重建是其出路所在。近几十年来，着...     

脱钙骨基质/磷酸钙复合骨水泥骨诱导活性观察

目的：观察磷酸钙骨水泥（CPC）中加入脱钙骨基质（DBM）后形成的复合骨水泥的成骨诱导活性。方法：将DBM/CPC复合骨水泥分别植入兔背肌肌袋内，于不同时间取材，通过组织学切片、ALP等手段观察异位诱导成骨情况。结果：术后2周，DBM/CPC复合骨水泥组可见间充质细胞增殖、聚集并包绕DBM骨粒。4周时，DBM已有部分吸收，并软骨样细胞和软骨样组织包裹。8周，DBM进一步吸收，软骨细胞和软骨组织逐渐成熟，新骨形成。12周，DBM吸收并被新骨组织部分或大部分代替且相互连接成片。ALP测定结果与组织学观察的新骨形成情况基本一致。结论：DBM/CPC复合骨水泥有较强的异位诱导成骨能力，诱导新骨的形成伴随着材料的降解，可以有效弥补单纯使用CPC时降解速度太慢和无骨诱导能力的不足。     

磷酸钙骨水泥的研究进展

磷酸钙骨水泥(CPC或CPBC)是一种自固型非陶瓷型羟基磷灰石类材料,1985年由Brown和Chow首先研制出用于骨移植和修复。它是一类以各种磷酸盐为主要成份,在生理条件下具有自固化能力及降解活性、成骨活性的无机材料。它还具有高度的生物相容性,可任意塑型,固化过程等温性等特点,是目前唯一既能自行固化又能产生骨传导效果的骨修复材料。     

聚磷酸钙纤维/磷酸钙骨水泥/微小颗粒骨修复骨缺损的实验研究

目的探讨聚磷酸钙纤维(calcium polyphosphate fibers,CPPF)、磷酸钙骨水泥(calcium phosphate cement,CPC)、自体微小颗粒骨复合材料修复骨缺损的能力。方法选用新西兰大白兔72只,双侧桡骨制成1.5cm骨缺损模型,随机分成6组分别植入。A组:CPPF/CPC/微小颗粒骨复合材料;B组:CPC/微小颗粒骨复合材料;C组:单纯微小颗粒骨;D组:CPPF/CPC复合材料;E组:单纯CPC;F组:空白对照组,不植入任何物质。在2、4、8、12周各时相点,分别进行大体观察、X线照片、组织学切片、扫描电镜观察及力学测试。结果A组在12周可使骨缺损修复,在骨缺损修复各时期,其成骨速度及成骨量均好于其他各组。结论CPPF/CPC/微小颗粒骨复合材料有良好的成骨能力、力学特性和生物相容性,有望成为骨组织工程中修复骨缺损的理想材料。     

脱钙骨基质/磷酸钙复合骨水泥骨诱导活性观察

目的:观察磷酸钙骨水泥(CPC)中加入脱钙骨基质(DBM)后形成的复合骨水泥的成骨诱导活性.方法:将DBM/CPC复合骨水泥分别植入兔背肌肌袋内,于不同时间取材,通过组织学切片、ALP等手段观察异位诱导成骨情况.结果:术后2周,DBM/CPC复合骨水泥组可见间充质细胞增殖、聚集并包绕DBM骨粒.4周时,DBM已有部分吸收,并软骨样细胞和软骨样组织包裹.8周,DBM进一步吸收,软骨细胞和软骨组织逐渐成熟,新骨形成.12周,DBM吸收并被新骨组织部分或大部分代替且相互连接成片.ALP测定结果与组织学观察的新骨形成情况基本一致.结论:DBM/CPC复合骨水泥有较强的异位诱导成骨能力,诱导新骨的形成伴随着材料的降解,可以有效弥补单纯使用CPC时降解速度太慢和无骨诱导能力的不足.     

脱钙骨基质/磷酸钙复合骨水泥骨诱导活性观察

目的:观察磷酸钙骨水泥(CPC)中加入脱钙骨基质(DBM)后形成的复合骨水泥的成骨诱导活性。方法:将DBM/CPC复合骨水泥分别植入兔背肌肌袋内,于不同时间取材,通过组织学切片、ALP等手段观察异位诱导成骨情况。结果:术后2周,DBM/CPC复合骨水泥组可见间充质细胞增殖、聚集并包绕DBM骨粒。4周时,DBM已有部分吸收,并软骨样细胞和软骨样组织包裹。8周,DBM进一步吸收,软骨细胞和软骨组织逐渐成熟,新骨形成。12周,DBM吸收并被新骨组织部分或大部分代替且相互连接成片。ALP测定结果与组织学观察的新骨形成情况基本一致。结论:DBM/CPC复合骨水泥有较强的异位诱导成骨能力,诱导新骨的形成伴随着材料的降解,可以有效弥补单纯使用CPC时降解速度太慢和无骨诱导能力的不足。     

复合型磷酸钙骨水泥研究进展

磷酸钙骨水泥(CPC)是一种自固化型羟基磷灰石类人工骨替代材料,具有良好的生物相容性和骨传导能力,已成为组织工程支架的一个重要分支.复合型CPC研究还处于初级阶段,添加剂对CPC的性能会有影响,并能不同程度地克服其缺点;对CPC进行成分改性可拓展其应用领域.该文对复合型CPC及其添加剂在骨水泥中的行为、作用疗效、原理的最新研究结果作一综述.     

促磷酸钙骨水泥吸收的研究进展

自固化磷酸钙骨水泥(CPC)自问世以来就备受关注。LeGeros曾总结其生物学特性有：(1)与骨矿物化学结构相似性；(2)可吸收性；(3)生物活性；(4)促进细胞功能表达；(5)骨传导性。但是和天然骨相比，CPC降解速度慢、没有韧性及约束力、不适合承重骨修复等不足使其临床应用受到很大限制。促进CPC吸收是当前CPC研究的热点之一。     

聚磷酸钙纤维/磷酸钙骨水泥复合材料修复骨缺损的实验研究

目的：探讨聚磷酸钙纤维（calcium polyphosphate fiber，CPPF）和磷酸钙骨水泥（calcium phosphate cement．CPC）复合材料修复骨缺损的能力及作为人工骨修复替代材料的可行性。方法：选用新西兰大白兔双侧桡骨制作骨缺损模型，将CPPF／CPC复合材料植入左侧骨缺损处，右侧骨缺损以自体微小颗粒骨植入作为实验对照，另做不植入任何物质的骨缺损作空白对照。在2、4、8、12周时分别进行大体观察、X线摄片、组织学切片观察，8、12周时进行扫描电镜观察及骨密度测定，12周时进行力学测试。结果：CPPF／CPC人工骨组与微小颗粒骨组骨缺损均完全修复，空白对照组骨缺损未见修复，CPPF／CPC与微小颗粒骨两组间X线评分、骨密度及力学测试指标比较，差异均无统计学意义（P〉0．05）。结论：CPPF／CPC复合材料具有良好的骨传导能力、力学特性及生物相容性，有望成为骨组织工程中修复骨缺损的理想材料。     

The effects of patient age on human osteoblasts' response to Ti-6Al-4V implants in vitro.

Osseointegrated implants are a common therapy for the elderly population as lifespan increases. Understanding the effects of age and sex on osseointegration is important for successful implant therapy. Therefore, the response of primary human osteoblasts (HOB) to implant materials was studied. HOBs were obtained by outgrowth of cells from bone from orthopaedic procedures and categorized as Young (Y), <15; Middle (M), 30-50; and Old (O), >60 years old. Initially the HOB phenotype was determined on tissue culture plastic. Alkaline phosphatase (ALP) staining and activity were significantly increased in HOBs from older patients. Message levels of type I collagen (COL), bone sialoprotein (BSP) and ALP were significantly higher (from 2.3- to 3.8-fold) in Y subjects compared to M and O patients at 2 weeks. Studies of the response of HOBs to implant materials were undertaken using Ti-6Al-4V disks prepared in a manner similar to orthopaedic implants. A 1.4-fold (p<0.05) increase in cell attachment was found in HOBs from Y compared with O in female subjects but not in male subjects. Cell proliferation at 24 h was not significantly different by age or sex, nor was DNA content different at 2 and 4 weeks. Mineralization in HOB-implant cultures was 2.3-fold higher in Y than in O, and 1.7-fold higher in Y compared to M HOBs from female but not male subjects at 4 weeks. Northern blot and RT-PCR analysis at 2 weeks of culture showed significantly higher levels (1.6-2.3-fold) of COL, BSP, and osteocalcin (OC) mRNAs in Y HOBs compared to M and O HOBs from female subjects. We conclude that human osteoblasts from older female patients have a decreased ability to form bone on implants.     

The acute metabolic effects of oral tricalcium phosphate and calcium carbonate

A double-blind study was performed to test the metabolic effects of tricalcium phosphate (TP) and calcium carbonate (CC) on serum calcium (SCa), serum phosphorus (SP), and immunoreactive intact serum parathyroid hormone (SPTH) levels in two groups of 24 subjects. The mean age of young subjects was 29.5 years, and elderly subjects, 65.9 years. These subjects fasted overnight for 12 hours, but with good hydration, before the tests. Following a 2-hour baseline-urine collection, 1200 mg elemental calcium (as CC or TP in tablet form) was chewed and ingested and 2-hour postload urines were collected. Blood was drawn immediately before and at 1, 2, and 4 hours after calcium load. The results showed that SCa and SP increased, whereas SPTH decreased with both preparations. The increment of SCa was similar after oral load of either calcium salt in both groups. The increment of SP after TP load was more than after CC. The urinary calcium/creatinine ratio (UCa/Cr) increased significantly after both preparations in the young group. The urinary phosphorus/creatinine ratio (UP/Cr) did not change significantly following TP, but decreased significantly after CC load in the young subjects. However, in the elderly individuals, the UP/Cr increased after TP load but did not change following CC, with statistical significance. The difference of urinary cyclic adenosine monophosphate/creatinine ratio (UcAMP/Cr) was not significant in both groups with either preparation. In summary, there was a similar rise in SCa and an equivalent fall in SPTH between TP and CC, in both young and elderly individuals.     

Prospective study of standalone balloon kyphoplasty with calcium phosphate cement augmentation in traumatic fractures

Prospective consecutive series cases study to investigate the clinical and radiological results of standalone balloon kyphoplasty and cement augmentation with calcium phosphate in traumatic fractures. Independent observer evaluation of radiological and computer tomography results, visual analogue scale (VAS), Roland–Morris score and complications with acute traumatic compression fractures type A, treated with a standalone balloon kyphoplasty and cement augmentation with calcium phosphate (Calcibon™); follow-up time at a mean of 30 months (24–37 months). From August 2002 to August 2003, consecutive patients with traumatic compression fractures (Magerl type A) without neurological deficit underwent standalone kyphoplasty with Calcibon. We report here the pre-, post-operative and the follow-up results, applying the VAS (0–10) for pain rating, the Roland–Morris (0–24) disability score, CT-scan examination, detailed radiographic evaluation of vertebral body (VB) deformity and segmental kyphosis measurement. The pre-operative X-ray measurements, VAS and the 7 days Roland–Morris scores are compared with the post-operative and the 30 months follow-up findings. Twenty-eight patients with 33 treated fracture levels were included in this study. The mean initial vertebral deformity (VB kyphosis) was 17°, corrected to a post-operative of 6°. We noted a loss of correction at the follow-up in comparison to the post-operative standing X-ray at 24 h of 3° vertebral deformity and 3° segmental kyphosis. The VAS score demonstrates a decrease over time from a mean of 8.7–3.1 at 7 days and to 0.8 at the last follow-up. The Roland–Morris disability score demonstrates a similar improvement. We noticed no major complications related to the procedure. The mean cement resorption after 1 year was 20.3% (0.3–35.3%) and is related to the individual biological resorption process and is not predictable. All patients with vertebral fractures as sole medical problem were discharged within 48 h. All active patients returned to the same work within 3 months with the same working ability as before the accident. Standalone balloon kyphoplasty is a potential alternative mini-invasive technique to reduce the fractures. However, due to the intrinsic characteristic of calcium phosphate cement (Calcibon) we recommend the application of this biological cement for standalone reduction and stabilisation only in fractures type A1 and A3.1 in young patient. In case of higher destruction levels of the VB, we propose the utilisation of Calcibon associated with posterior instrumentation. Having regard to the pointed out indications, our preliminary results demonstrate a new possibility to treat this kind of fractures, allowing a rapid handling of pain, early discharge and return to normal activities.     

Short-term microvascular response of striated muscle to cp-Ti, Ti-6Al-4V, and Ti-6Al-7Nb.

Due to excellent mechanical properties and good corrosion resistance, titanium-aluminium-vanadium (Ti-6Al-4V) and titanium-aluminium-niobium (Ti-6Al-7Nb) are extensively used for orthopedic surgery. Concern has been voiced concerning the implications of the constituent vanadium in Ti-6Al-4V on the surrounding environment. Particularly in osteosynthesis where the alloys stand in direct contact to skeletal muscle, undesirable biologic reactions may have severe consequences. In a comparative study, we assessed in vivo nutritive perfusion and leukocytic response of striated muscle to the metals Ti-6Al-4V, Ti-6Al-7Nb, and commercially pure titanium (cpTi), thereby drawing conclusions on their short-term inflammatory potential. In 28 hamsters, utilizing the dorsal skinfold chamber preparation and intravital microscopy, we quantified primary and secondary leukocyte-endothelial cell interaction, leukocyte extravasation, microvascular diameter change, and capillary perfusion in collecting and postcapillary venules of skeletal muscle. A manifest discrepancy between the metals concerning impact on local microvascular parameters was not found. All metals induced an only transient and moderate inflammatory response. Only a slight increase in leukocyte recruitment and a more sluggish recuperation of inflammatory parameters in animals treated with Ti-6Al-4V compared to the other two metals suggested a minor, overall not significant discrepancy in biocompatibility. Gross toxicity of bulk Ti-6Al-4V on surrounding tissue could not be found. Conclusively, the commonly used biomaterials Ti-6Al-4V, Ti-6Al-7Nb, and cpTi induce an only transient inflammatory answer of the skeletal muscle microvascular system. Our results indicate that on the microvascular level the tested bulk Ti-alloys and cpTi do not cause adverse biologic reactions in striated muscle.     

The effects of citrate on hydroxyapatite induced calcium oxalate crystallization and on the formation of calcium phosphate crystals

Summary The addition of different amounts of hydroxyapatite crystals (HAP) to a solution, metastably supersaturated with respect to calcium oxalate (CaOx) resulted in heterogenous crystallization at seed concentrations exceeding 0.2 mmol/l. The induction period varied between 1 and more than 8 h with the shortest period for a seed concentration of 2 mmol/l. Addition to the system of 1 and 2% of whole urine and citrate in concentrations corresponding to approximately 1% of that found in normal urine inhibited the crystallization for as long as 4 h. In a system supersaturated with respect to calcium phosphate (CaP) the total number of crystals was markedly reduced by citrate concentrations exceeding 0.5 mmol/l. The fractions of medium sized and large crystals were sharply reduced and small crystals predominated at higher citrate concentrations. This might indicate effects of citrate on both crystal growth and crystal aggregation. We conclude that increased citrate concentrations during treatment with alkali leads to a significant inhibition of CaOx growth on HAP as well as to a prevention of the formation of large CaP crystals from solutions supersaturated with respect to CaP.     

磷酸钙水泥降解成骨机制的研究

目的: 研究磷酸钙水泥 (CPC) 降解吸收成骨的机制。方法: 制备羊胫骨平台压缩性骨折模型, 植入CPC填充骨缺损。3个月时拍X线片、取材制作不脱钙切片, 观察CPC的组织学变化。结果: CPC吸收迅速, X线片可见 2只动物几乎吸收完毕, 另 3只已大部被吸收。组织学观察可见到许多骨水泥吸收骨形成单位, 吸收的骨水泥由新生骨填充, 未见纤维组织形成。结论: CPC吸收成骨机制与正常骨重建过程相类似, 骨水泥吸收与新生骨形成同步协调进行。     

Reduction of fretting corrosion of Ti-6Al-4V by various surface treatments

Titanium and titanium-6% aluminum-4% vanadium (Ti-6Al-4V) are known to be biocompatible and corrosion resistant. However, there have been numerous reports of elevated tissue levels of titanium due to passive dissolution, wear, or fretting corrosion of implants. Studies were undertaken to determine whether the fretting corrosion of Ti-6Al-4V could be reduced by surface treatment of one or both surfaces in a fretting situation. Three different surface treatments were studied: ion implantation, physical vapor deposition nitriding, and plasma ion nitriding. The specimens used were screws fretting against the countersinks of a two-hole plate. Fretting corrosion was assessed by weight loss, by chemical analysis of test solutions, and by scanning electron microscopy. Surface treatment of one component, the screws, resulted in reduction in the release of titanium to only 18–32% of that seen with the untreated controls. Weight loss of the untreated plates fretted against physical vapor deposition nitrided screws and plasma ion nitrided screws was reduced to 31 and 38% of the control, respectively. The weight loss of plasma nitrided screws was only 30% that of the control. Nitriding of both plates and screws resulted in a further decrease in plate weight loss and metal release. Plasma ion nitriding of both components had the most significant effect, with the weight loss and titanium release being only 11 and 2% of the control values, respectively.     

磷酸钙骨水泥在椎体成形术中的实验研究

目的 :模仿椎体成形术观察磷酸钙骨水泥 /聚甲基丙烯酸甲酯植入椎体后与椎体界面间的组织学差异。方法 :将PMMA和CPC植入到犬椎体 ,通过X线、CT、光镜、扫描电镜观察 2种材料与椎体界面间的微观结构变化。结果 :PMMA与椎体之间的结合是单纯的机械连接未能达到生物机械固定 ,CPC与骨界面间无排异反应的表现 ,是直接的骨小梁与生物材料之间的生物连接。结论 :磷酸钙骨水泥是椎体成形术中的一种比较理想的替代材料     

磷酸钙骨水泥的显影性及生物力学实验研究

目的:探讨适用于经皮椎体成形术的磷酸钙骨水泥(calciumphosphatecement,CPC)与显影剂混合物比例及其生物力学性能。方法:根据加入显影剂比例不同分为4组,A组为单纯CPC,B组为CPC+10%质量百分比(wt)碘必乐,C组为CPC+20%wt碘必乐,D组为CPC+30%wt碘必乐。各组分别制成直径0.5cm、高2.5cm的圆柱体,测定各组的可注射时间、显影效果和力学特性,根据测试结果选择合适比例的混合物进行尸体椎体实验,测定椎体修复前后的强度和刚度。结果:在X线下显影的灰度值A组为2163.6±64.6,B组为1541±97.3,C组为1467.3±68.1,D组为1159.8±146.3;A组与另3组比较P<0.05,B组与C组比较P>0.05,B组与D组比较P<0.05,C组与D组比较P<0.05。可注射时间分别为5.5、23、45和67min;抗压强度分别为8.28±4.17、3.64±0.31、2.28±0.25和0.99±0.14mPa,各组间比较有显著性差异(P<0.05)。以CPC+10%wt碘必乐对尸体的压缩骨折椎体行椎体成形术,椎体修复前后的强度分别为631.99±236.62N和940.77±336.54N,椎体修复前后的刚度分别为119.230±44.882N/mm和157.32±37.37N/mm,注射前后比较均有显著性差异(P<0.05)。结论:加入10%wt碘必乐的CPC具有较好的显影性、足够的可注射时间和良好的力学特性,是经皮椎体成形术(PVP)可供选用的填充材料。