新型聚醚醚酮复合材料生物安全性的初步检测

目的:通过体内及体外试验,初步检测自行合成的聚醚醚酮(Polyetheretherketone, PEEK)复合材料的生物安全性。方法:采用MTT、急性全身毒性试验、黏膜刺激试验和溶血试验检测PEEK复合材料的体内和体外生物安全性。结果:MTT结果显示:PEEK复合材料浸提液对细胞生长及形态没有影响;急性全身毒性试验显示:试验组大鼠在观察期内均无死亡、中毒反应,饮食正常,精神状态良好。试验组大鼠心脏、肝脏、肾脏、脾脏重要器官肉眼及镜下观察无异常,组织切片与对照组无明显差异,未见病理改变。可以认为PEEK复合材料不会引起中毒反应;黏膜刺激试验显示:经肉眼观察试验组黏膜组织正常,无红斑、糜烂、溃疡现象;镜下观察,与对照组无明显差异,镜下评分＜4。综合肉眼及镜下观察结果显示,PEEK复合材料对口腔黏膜无刺激性;溶血试验显示:试验组测得溶血率为0.663%,满足中华人民共和国医药行业标准(YY)规定的溶血率小于5%的要求,所以PEEK复合材料不会引起溶血反应。结论:PEEK复合材料具有良好的生物安全性。     

硫酸改性后的聚醚醚酮对小鼠骨髓巨噬细胞生存活性的影响

目的:观察硫酸酸蚀种植体材料聚醚醚酮(PEEK)形成2D孔状结构和3D网状结构表面,比较其对小鼠骨髓来源巨噬细胞(BMDMs)生存活性的影响.方法:根据细胞培养承载材料表面结构将BMDMs分为3组:对照组(光滑表面,N);3D网状结构组(3D)和2D孔状结构组(2D).运用场发射扫描电子显微镜观察样本表面形貌,接触角测...     

The effects of three cold plasma treatments on the osteogenic activity and antibacterial property of PEEK

ObjectiveThis study examines the differences in osteogenic activity and antibacterial property among polyetheretherketone (PEEK) treated by three types of cold plasma.MethodsStandard PEEK specimens were randomly assigned to four groups, which were named according to the treatment: PEEK-C (untreated), PEEK-A (Ar cold plasma treatment), PEEK-N (N₂ cold plasma treatment), and PEEK-AN (90% Ar and 10% N₂ mixed cold plasma treatment). Physical and chemical properties of the specimen surfaces were determined by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and drop shape analyzer (DSA). MC3T3 osteoblasts were used in vitro to determine the osteogenic activity by cell adhesion morphology observation, cell counting-kit 8 (CCK-8) assay, and alkaline phosphatase (ALP) activity assay. Streptococcus mutans and Staphylococcus aureus were used in vitro to determine the antibacterial property by a plate colony-counting method and bacterial adhesion morphology observation.ResultsSEM and AFM analysis showed that the PEEK-C surface was smooth, whereas matrix-arranged nanoprotrusions appeared on the surface of the experimental groups: scaly nano-protrusions appeared on the PEEK-A and PEEK-AN surfaces, while dendritic nanoprotrusions appeared on the PEEK-N surface. Among the experimental groups, PEEK-AN had the finest surface nanoprotrusions. The roughness of the experimental groups increased compared with the PEEK-C group: the PEEK-N group was the roughest with a Ra of 192.60 ± 5.89 nm and PEEK-A was the smoothest with a Ra of 99.60 ± 5.43 nm. The hydrophilicity of the experimental groups was significantly enhanced compared with the PEEK-C group, among which, PEEK-N was the strongest and PEEK-A the weakest. The osteogenic activity and antibacterial property of the experimental groups displayed a remarkable increase compared with the PEEK-C group. Among the experimental groups, PEEK-N displayed the best osteogenic activity while PEEK-AN possessed the strongest antibacterial property. The osteogenic activity and antibacterial performance of PEEK-A were the weakest. Among these treatments, the N₂ cold plasma treatment was the most suitable modification method for PEEK application in dental implant.SignificanceCold plasma treatment is a promising method to improve PEEK osteogenic activity and antibacterial properties. This study provides a theoretical basis for future research on PEEK cold plasma treatment.     

Lithium doped silica nanospheres/poly(dopamine) composite coating on polyetheretherketone to stimulate cell responses,improve bone formation and osseointegration

Osseointegration is crucial for early fixation as well as long-term success of orthopedic implants. Bioactive composite containing lithium doping silica nanospheres (LSNs) and poly(dopamine) (PDA) were coated on polyetheretherketone (PK) surface (LPPK), and effects of the LSNs/PDA composite (LPC) coating on the biological properties of LPPK were assessed both in vitro and in vivo. Results showed that LPPK with improved bioactivity remarkably promoted apatite mineralization in simulated body fluid (SBF) compared with PDA coated on PK (PPK) and PK. Moreover, the LPPK remarkably stimulated rat bone marrow stromal cells (rBMSCs) responses compared with PPK and PK. Furthermore, the LPPK significantly promoted bone tissues responses in vivo compared with PPK and PK. It could be suggested that the improvements of cells and bone tissues responses were attributed to the surface characteristics of the bioactive LPC coating on LPPK. The LPPK would be a great candidate for orthopedic and dental applications.     

Characterization of PEEK biomaterials using the small punch test

The small punch test is widely used to characterize the ductility and fracture resistance in metals and ceramics, when only a small volume of material is available. This study was conducted to investigate the suitability of the small punch test for characterizing polyetheretherketone (PEEK) polymeric biomaterials for changes in material grade, crystallinity, and molding process. The small punch test reproducibly characterized the mechanical behavior of PEEK and was able to distinguish differences induced by molding process alterations and annealing. Peak load was most sensitive to changes in crystallinity, grade, molding process, and increased with increasing crystallinity, but decreased with the addition of image contrast materials. The ultimate displacement was negatively correlated with crystallinity. Molding process conditions had the greatest influence on metrics of the small punch test, when compared with the effects of annealing and the addition of a radiopacifier. The results of this study validate the small punch test as a repeatable method for measuring the mechanical behavior of PEEK biomaterials.     

Using Kubelka-Munk reflectance theory to predict optimal pink composite thickness and shade with an opaqued PEEK background for a final gingival color: An in vitro study

ObjectivesThe aims of this study were to demonstrate and evaluate how Kubelka-Munk (K-M) reflectance theory is used to adjust the color of the opaqued PEEK backing and the color and thickness of the resin composite layers in different thicknesses in order to minimize the color difference from a target gingival color.MethodsPEEK specimens were opaqued with either a dark or a light opaquer. Composite resin layers in 3 different colors were fabricated in varying thicknesses. Reflectance of opaqued PEEK and composite layers was determined using a spectroradiometer. Kubelka–Munk (K-M) absorption (K) and scattering (S) coefficients were derived for each material and then K-M reflectance theory was then used to predict the reflectance of each composite disk as layered on each backing. The color of the opaqued PEEK backings alone and the color of 12 pink composite layers on opaqued PEEK backings was calculated for the CIE D65 Illuminant. Composite resins in 3 different color were then bonded to the opaqued PEEK specimens and color differences of these specimens from the theoretical colors were determined.ResultsThe ?E00 values ranged from 0.45 to 1.29 units for the bonded pink specimens and the K-M theory. K-M theory was validated as a viable predictor of gingival color using pink composite bonded to opaqued PEEK background.SignificanceUsing K-M theory to predict the gingival color of pink composite bonded to opaqued PEEK eliminates the need to make many specimens of different thicknesses that would otherwise be required to find an acceptable color match.     

Comparison of Long‐Term Outcomes between the n‐HA/PA66 Cage and the PEEK Cage Used in Transforaminal Lumbar Interbody Fusion for Lumbar Degenerative Disease: A Matched‐Pair Case Control Study

ObjectiveThe nanohydroxyapatite/polyamide‐66 (n‐HA/PA66) cage is a novel bioactive nonmetal cage that is now used in some medical centers, while the polyetheretherketone (PEEK) cage is a typical device that has been widely used for decades with excellent clinical outcomes. This study was performed to compare the long‐term radiographic and clinical outcomes of these two different cages used in transforaminal lumbar interbody fusion (TLIF).MethodsIn this retrospective and matched‐pair case control study, we included 200 patients who underwent TLIF from January 2010 to December 2014 with a minimum 7‐year follow‐up. One hundred patients who used n‐HA/PA66 cages were matched with 100 patients who used PEEK cages for age, sex, diagnosis, and fusion level. The independent student''s t‐test and Pearson''s chi‐square test were used to compare the two groups regarding radiographic (fusion status, cage subsidence rate, segmental angle [SA], and interbody space height [IH]) and clinical (Oswestry Disability Index [ODI], and Visual Analog Scale [VAS] for back and leg) parameters preoperatively, postoperatively, and at the final follow‐up.ResultsThe n‐HA/PA66 and PEEK groups had similar fusion rates of bone inside and outside the cage at the final follow‐up (95.3% vs 91.8%, p = 0.181, 92.4% vs 90.1%, p = 0.435). The cage union ratios exposed to the upper and lower endplates of the n‐HA/PA66 group were significantly larger than those of the PEEK group (p < 0.05). The respective cage subsidence rates in the n‐HA/PA66 and PEEK groups were 10.5% and 17.5% (p = 0.059). There were no significant differences between the two groups in the SA, IH, ODI scores, or VAS scores at any time point. The n‐HA/PA66 group showed high fusion and low subsidence rates during long‐term follow‐up.ConclusionBoth n‐HA/PA66 and PEEK cages can achieve satisfactory long‐term clinical and radiographic outcomes in TLIF. However, the n‐HA/PA66 group showed significantly larger cage union ratios than the PEEK group. Therefore, the results indicated that the n‐HA/PA66 cage is an ideal alternative material comparable to the PEEK cage in TLIF.     

医用聚醚醚酮材料骨整合改性的研究进展

聚醚醚酮（PEEK）材料具有良好的生物相容性、优异的机械性能、与骨组织相似的力学性能等优点,目前已广泛应用于临床各个领域。由于固有的生物惰性,使种植体与骨组织不相整合,从而限制了其作为骨科植入材料的应用。提高PEEK骨整合性成为目前研究的热点。研究者将具有促进成骨细胞增殖和分化的材料（如生物陶瓷、金属材料、生物因子等）通过物理或化学方式修饰于材料表面,或者采用表面物理修饰（如粗糙度、孔隙率、纳米结构等）提高其骨整合性。随着研究的逐步深入,PEEK的成骨活性得到增强,在临床上有了更大的应用前景。本文主要对上述提到的近些年用于提高PEEK生物活性的方法作一综述,旨在为研究者提供参考,并对未来发展提出展望。     

聚醚醚酮棒椎弓根螺钉系统在多节段腰椎退行性疾病治疗中的应用

目的探讨聚醚醚酮(PEEK)棒椎弓根螺钉内固定系统在多节段腰椎退行性疾病中的应用价值。方法回顾性分析2014年9月至2015年5月应用PEEK棒椎弓根螺钉内固定系统治疗的多节段腰椎退行性疾病患者,共11例,所有患者随访资料均完整。其中男5例,女6例,平均年龄60.4±8.7岁。其中9例患者固定4个节段,5例患者固定范围为L_3-S_1,4例患者固定范围为L_2-L_5,2例患者固定5个节段,均固定至L_2-S_1。根据病变的情况在固定节段内选择性行椎间融合,其中2例患者融合了2个节段,7例患者融合了1个节段,2例患者未行椎间融合。通过术前、术后3月、6月、1年及2年的Oswestry功能障碍指数(Oswestry Disfunctional Index)和视觉模拟评分(Visual Analogue Scale,VAS),评估临床疗效。通过腰椎侧位X线观察融合节段的椎间高度指数(DHI),腰椎过伸过屈X线观察椎间活动度(Range of Motion,ROM)变化情况,术后2年CT二维重建观察椎间融合情况,术后2年CT三维重建观察有无PEEK棒断裂或变形。结果 11例患者平均随访24.6±1.7(22~28)月。平均手术时152±25(120~210)分钟,平均术中失血518±248(300~1000)mL。ODI评分术前49.6±12.2,末次随访15.5±3.7,同术前相比差异有统计学意义(P=0.000);VAS评分术前8.1±0.8,末次随访时1.7±0.6,同术前相比差异有统计学意义(P=0.000)。融合节段的DHI术前0.343±0.091,末次随访DHI 0.321±0.069,差异无统计学意义(P=0.070)。在24个非融合节段中,ROM术前平均9.3°±1.5°,末次随访2.3°±0.5°,术前术后变化差异有统计学意义(P=0.000)。行椎间融合的11个节段在术后2年随访时共8例患者获得骨性融合,融合率为72.7%。术后2年随访时无PEEK棒断裂,变形情况出现。结论 PEEK棒椎弓根螺钉内固定系统治疗多节段腰椎退行性病变安全有效,但长期疗效有待进一步随访观察。     

Osseointegration of machined,injection moulded and oxygen plasma modified PEEK implants in a sheep model

Machined and injection moulded polyetheretherketone (PEEK) implants with and without an oxygen plasma modification were prepared and implanted in sheep cancellous and cortical bone. After 4, 12 and 26 weeks, osseointegration was evaluated through mechanical push-out tests and histomorphometry. In the cancellous bone, push-out force increased with time, a trend toward higher force was observed for machined compared to moulded, and oxygen plasma modified compared to unmodified. On-going remodelling of the bone was detected in the periphery of the implants at 4 weeks. Minimal or no inflammation was observed with all the implants at all locations and time-points. Bone-implant contact (BIC) was quantified at all-time points and locations for all the four PEEK implant surfaces. The BIC values ranged from 15 to 75% with an average of 29 ± 13% in the cancellous bone and 25–65% with an average of 50 ± 12% in the cortical bone. In the cortical bone the BIC increased significantly from 4 to 26 weeks. This in vivo study has identified that surface topography of PEEK implants influences osseointegration. In addition, oxygen plasma has the potential to increase bone-implant interface stability. This study provides a unique reference for further modifications and in vivo assessment of PEEK implants.