含氟纳米羟基磷灰石-聚醚醚酮复合材料表面变形链球菌黏附和生物膜形成初探

Study of oral microbial adhesion and biofilm formation on the surface of nano-fluorohydroxyapatite/polyetheretherketone composite

目的 分析含氟纳米羟基磷灰石（nano-fluorohydroxyapatite,n-FHA）-聚醚醚酮（polyetheretherketone,PEEK）复合材料表面变形链球菌的黏附情况和不同时间点生物膜的形成情况,探索n-FHA-PEEK作为新型口腔种植修复材料的可行性.方法 制备n-FHA-PEEK、纳米羟基磷灰石（nano-hydroxyaptite,n-HA）-PEEK和PEEK圆片形试件,分别在3组材料表面接种口腔变形链球菌,检测接种1、2、4h时（每组每个时间点样本量为3）变形链球菌的黏附情况;3组试件接种口腔混合菌（变形链球菌、黏性放线菌和牙龈卟啉单胞菌）（每组样本量为3）,利用激光扫描共聚焦显微镜连续观察培养3、7、14 d时各组试件表面生物膜的形成情况及膜内死菌/活菌构成变化.结果 黏附2h时n-FHA-PEEK组和PEEK组细菌黏附量（分别为0.496±0.008和0.503±0.002）均与n-HA-PEEK组（0.543±0.015）差异有统计学意义（P＜0.01）,而1、4h时3组间细菌黏附量差异均无统计学意义（P＞0.05）.培养3、7、14d时3组材料表面生物膜形貌基本一致,厚度接近,均约90 μm.培养7d时n-HA-PEEK和n-FHA-PEEK组材料表面可见少量死菌;14d时3组均出现明显死菌,且n-FHA-PEEK组死菌最明显,n-HA-PEEK组其次,PEEK组最少.结论 磷灰石成分,尤其是含氟的磷灰石成分,可降低PEEK表面的细菌黏附量,增加生物膜内死菌数量;n-FHA-PEEK有望成为一种新型的口腔种植修复材料.

Objective To develop novel polyetheretherketone（PEEK） based nanocomposites which possess the favorable antibacterial property,and to investigate the oral microbial adhesion and biofilm formation on the surfaces of PEEK,nano-fluorohydroxyapatite（n-FHA）-PEEK and nano-hydroxyaptite （n-HA）-PEEK.Methods The bacterial adhesion and biofilm formation on the surfaces of n-FHA-PEEK,n-HA-PEEK were investigated via microbial viability assay kit and laser scanning confocal microscope （LSCM）,respectively,with pure PEEK as control group.Results No significantly statistical difference were found in the bacterial adhesion amounts on the surfaces of n-FHA-PEEK,n-HA-PEEK and PEEK at 1 h and 4 h.However,the number of bacteria on the n-FHA-PEEK surface decreased dramatically at 2 h（0.496±0.008） compared with n-HA-PEEK groups（0.543± 0.015,P〈0.01）.Although the biofilms formation on surfaces observed by LSCM had similar morphology and thickness at 3,7,14 d,that on the n-FHA-PEEK surface showed the highest dead-to-live bacteria ratio among the three materials at 14 d.Conclusions The combination of n-HA,especially for the n-FHA could inhibit the bacteria adhesion and accelerate the bacterial death,eventually may have an influence on the structure of biofilms and reduce the risk of periimplantitis.Therefore,n-FHA-PEEK nanocomposites presented a good prospect for clinical applications as dental implant materials.