Influence Of Different Power Nd:YAG Laser On The Biocompatibility Of PEEK

Objective:This experiment used different power of Nd: YAG laser to process the surface of biological inert implant material-polyether ether ketone(PEEK),assess the physical and chemical properties of specimens by a series of tests and evaluate the effect of Nd: YAG laser treatment on the biological properties of PEEK through a series of cytological experiments,establishing the solid basis of application in oral implantology for PEEK.Methods:The PEEK specimens were randomly divided into 4 groups: control group(without any processing),0.5 W group(using the power of 0.5 W Nd: YAG processing),1 W group(using the power of 1 W Nd:YAG processing)and 1.5 W group(using the power of 1.5 W Nd:YAG processing).The PEEK specimens were irradiated vertically by handheld Nd:YAG laser device at the distance of 1 mm approximately from the surface,with a rate of 2 mm/s,and the interval of irradiation distance is 1 mm;Scanning electron microscopy(SEM)was used to observe the surface morphology of the specimens in each group;Atomic force microscope(AFM)was used to measure the roughness of the specimens;Water contact angle measuring instrument was used to evaluate the hydrophilicity of the specimens in each group.MC3T3-E1 cells were cultivated with specimens,DAPI dye liquor was used to dye the adhesion cells in each specimen for evaluating cell adhesion performance of material;CCK-8 kits was used to assess cell proliferation activity of each group;SEM was used to observe the morphology and quantity of cells adhering on the surface of PEEK in each group;ALP kit was used to evaluate the activity of alkaline phosphatase of each sample.Results:(1)After different power of Nd: YAG laser processing,PEEK surface microscopic morphology had a change,when the power is 0.5 W,PEEK surface uplifted,ruptured,and there are less pore forming with a smaller diameter and scattered distribution,when power increased to 1.0 W,the diameter and distribution range of pores on specimen surface increased,melting and sintering phenomenon occurs on the specimen surface of 1.5 W group,protuberances with higher density and smaller diameter generated;AFM results show that the roughness of each group increased after laser treatment.The result of water contact angle shows that the hydrophilicity of the material is improved.The results of XPS element analysis showed that the content ratio of C and O increased after Nd:YAG laser treatment.(2)Nd:YAG laser treatment promoted the adhesion and proliferation of cells on the surface of PEEK to a certain extent,but couldn’t improve the osteogenic effect of materials.Conclusions:In a certain power range,Nd:YAG laser can improve the hydrophilicity and roughness of PEEK to a certain extent,and promote the adhesion and proliferation of cells to a certain extent,but it has no obvious effect on the osteogenic differentiation of cells.