【作者】 吴艳；

【导师】 王勤涛；

【作者基本信息】 第四军医大学 ， 口腔临床医学， 2010， 硕士

【摘要】 膨体聚四氟乙烯膜(ePTFE)是目前用于牙周引导组织再生(guided tissue regeneration,GTR)和引导骨再生(guided bone regeneration, GBR)的常用屏障膜,既可以保证以及诱导具有形成新附着能力的牙周膜细胞优先占领根面,从而获得牙周支持组织再生;也可以保证和诱导成骨细胞免受干扰修复骨组织缺损。屏障膜的理化性能和生物学特性直接影响GTR的治疗效果。在临床应用过程中,软组织瓣如果封闭不严密或者裂开,则将使ePTFE膜暴露于口腔环境,细菌对外源性材料的粘附易引起感染从而影响治疗效果。目前常用的方法多是在膜表面涂敷抗生素,但释放量和维持时间均有限,疗效并不如意。如能使ePTFE膜本身具有抗细菌粘附的能力,无疑对提高GTR术和GBR术的治疗效果具有重要的意义。本实验采用等离子注入(plasma immersion ion implantation,PIII)技术,对ePTFE膜表面注入氧等离子体,观察细菌对处理后的膨体聚四氟乙烯膜粘附性能的变化。将等离子体注入装置充满氧气,加入射频使氧气等离子体化。采用不同参数对ePTFE膜进行表面处理,电镜观察处理后各组样本表面形貌;X射线光电子能谱(XPS)检测样本表面化学组成以及元素的高分辨谱;用衰减全反射傅立叶红外光谱(HATR-FTIR)检测试样表面化学组成;接触角测定仪检测表面疏水性的变化;并通过体外细菌粘附实验,观察金黄色葡萄球菌、变形链球菌对各组样本的粘附性,并观察细菌生物膜的形成。结果:1. ePTFE膜经不同参数氧等离子处理后,表面呈粗糙形貌、疏水性、自由能改变。长脉冲组表面形貌改变最大,呈蚀刻性粗糙形貌,接触角增大,表面自由能减小;XPS和HATR-FTIR分析处理后的ePTFE表面含有C-O、C=O,其中以C=0键为主要的含氧官能团。长脉冲处理组含氧量和其它两组相比较多。2.细菌粘附实验发现长脉冲氧PIII处理后,ePTFE膜细菌粘附明显减少;短脉冲组细菌粘附无明显变化;且不同厚度ePTFE膜细菌粘附率不同。3.荧光染色标记后,长脉冲组ePTFE膜表面细菌稀少,而短脉冲组和对照组细菌与长脉冲组相比细菌明显密集。结论:与未处理ePTFE膜相比,两种厚度改性ePTFE膜表面形貌、物理化学特征、疏水性、表面能均发生改变。长脉冲PIII处理组改变最大,表面有小丘状结构,呈蚀刻性粗糙形貌;疏水性增大、表面能降低,这些效应均与等离子体对样本表面处理有关;氧等离子体改性ePTFE膜可以使细菌对其粘附力明显降低,抑制生物膜的形成,这些作用与氧等离子体处理改变了ePTFE膜表面理化特性有关,从而抑制细菌对材料的表面粘附。更多还原

【Abstract】 Expanded polytetrafluoroethylene(ePTFE)is widely used to improve new attachment in GTR and bone augmentation in GBR. It is important for physical , chemical properties of barrier membranes in GTR and GBR. If the soft tissue flap is not tightly closed, ePTFE membrane maybe exposed to the oral environment, and bacterial adhering in materials may induce membrane related infection. The current method to overcome this shortage is to coat antibiotics in the surface of membranes, but it is unsatisfactory for releasing time and maintenance time of antibiotics. If ePTFE membrane has its own anti-adhesion ability of bacteria, it is a good news for GTR. Plasma immersion ion implantation (PIII) has been used to modify the surface of ePTFE membrane. The bacterial adhesion to the modified ePTFE was studied quantitatively. Oxygen gas was bled into the chamber, rf power was introduced to plasma discharge chamber to generate the oxygen plasma. In order to investigate the effects of PIII treatment, different sets of instrumental parameters were used. The modified ePTFE samples were investigated by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy and horizontal attenuated total fourier transform infrared spectroscopy (HATR-FTIR), and measured by the sessile drop method for static contact angles. The bacterial adhesion efficiency of staphylococcus aureus and streptococcus mutans to the modified ePTFE was studied quantitatively, and the accumulation of in vitro S. mutans biofilm on the modified ePTFE was investigated.The results indicated that:1. The morphological difference is observed of modified ePTFE. It revealed that PIII changed surface morphology, hydrophobicity and surface energy. More oxygen-containing, rougher, and more hydrophobicity surface were produced on ePTFE after long pulse, C-O and C=O is observed by XPS and HATR-FTIR, and C =O as the main oxygen-containing functional groups2. It manifested that long pulse PIII treated ePTFE significantly reduced the bacterial adhesion in vitro. There is no difference between short pulse PIII treated and blank gruops. The bacterial adhesion efficiency of the different ePTFE were different.3. After fluorescence-labeling, less bacteria in long pulse PIII ePTFE, and more bacteria in short pulse PIII ePTFE and virgin samples.Conclusions:The morphological difference is observed on modified ePTFE. It revealed that PIII changed surface morphology, property, hydrophobicity and surface energy of ePTFE. More oxygen-containing, rougher, and more hydrophobicity surface were produced on ePTFE after long pulse. A typical rough surface of colliculus and lower surface energy were also observed. It can reduce bacteria adherence and prevent to form biofilm.更多还原