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目的 探讨氯己定修饰多孔钛的抗菌性能及其对成骨细胞黏附及增殖的影响,为构建具有抗菌性能的种植体提供依据.方法 选取直径10.0 mm、厚度1.5 mm的光滑纯钛试件,以碱热处理后钛试件为对照组、碱热处理+共价结合氨基硅烷的钛试件为硅烷化组、碱热处理+共价结合氨基硅烷+戊二醛接枝氯己定的钛试件为接枝组.用扫描电镜观察各组试件表面形貌、X射线光电子能谱分析元素组成、接触角测量仪分析亲水性(每组6个)、酸性橙Ⅱ法分析氨基或亚胺基团含量(每组5个);用光密度法测定氯己定组5个钛试件的氯己定接枝密度;用死活菌染色及扫描电镜观察、涂板计数法、抑菌环法评价各组钛试件抗菌能力,甲基噻唑基四唑法评价各组与成骨细胞共培养1、3、5d后的细胞活性,细菌-细胞共培养评价有菌环境中各组钛试件的细胞黏附能力.结果 氯己定接枝后多孔钛表面的孔隙减小,C、N、Cl原子百分含量增加,接触角下降至37.5°±4.0°,氯己定接枝密度为(5.07±0.39) μg/cm2;死活菌染色及扫描电镜显示氯己定组仅有少量细菌黏附且细菌壁破裂;氯己定组菌液涂板仅见零星菌落,抑菌环透亮;细胞培养1、3d氯己定组细胞活性与对照组差异无统计学意义(P＞0.05),培养5d氯己定组细胞活性(0.547±0.087)显著小于对照组(0.751±0.056)(P＜ 0.05);细菌-细胞共培养显示对照组钛表面黏附大量细菌,氯己定组钛表面黏附大量细胞,且细胞形态良好.结论 氯己定接枝修饰的多孔钛具有良好的抗菌能力,在有菌环境中可保障细胞黏附.“,”Objective To investigate the antibacterial properties and the osteoblast-compatibility of chlorhexidine (CHX)-modified porous titanium.Methods Smooth pure titanium specimen with diameter of 10.0 mm and thickness of 1.5 mm treated with alkali heat method were set as control group.Those with covalent conjugation of aminosilane were set as silane group,and those with CHX grafted by glutaraldehyde were set as CHX group.Scanning electron microscope (SEM) was used to observe the surface morphology and element compositions were detected by X-ray photoelectron spectroscopy.Hydrophilicity was analyzed by surface water contact angle test (n=6),while surface amino/imine groups quantification were performed through acid orange Ⅱ (n=5) and the CHX was quantified by optical densitometric method (n=5).Live/dead bacterial staining,the morphology of adherent bacteria by SEM,plate counting method and inhibition zone method were executed to evaluate the antibacterial property of the samples.Osteoblast compatibility was evaluated by methyl thiazolyl tetrazolium.Cell-bacterial co-culture was conducted to evaluated the cell viability on the samples under the circumstance with bacteria.Results After CHX grafting,pores on the titanium surface were decreased,while the atom ratio of C,N,Cl increased and the water contact angle decreased to 37.5°±4.0°.The density of CHX on the surface was (5.07±0.39) μg/cm2.The results of live/ dead bacterial staining and the morphology of adherent bacteria showed that only little dead bacterial (bacterial wall rupture) adherent on the surface of CHX group,which proved that the modified surface could inhibit bacteria adhesion and even destroyed bacteria;the plate counting displayed sporadic colonies and a transparent inhibition zone could be observed,which demonstrated that CHX group could suppress bacteria multiplication from surrounding environment.When incubating for 1 and 3 days,the cell viability of CHX group showed no significant difference from that of control group (P ＞ 0.05);when incubating for 5 days,the value of cell viability of CHX group was 0.547±0.087,and this was significantly lower than that of the control group (0.751±0.056) (P ＜ 0.05),demonstrating a slight inhibition of cell proliferation by CHX.The results of bacteria-cell co-culture for 3 days showed that a mass of bacteria adhered on the surface of the control group while considerable cells adhered on the surface of CHX group and exhibited a good shape.Conclusions Porous titanium surface grafted by CHX showed an excellent antibacterial properties and allowed cell adhesion in bacterial circumstance,providing immediate implantation options for patients with bad oral health.