脉冲Nd:YAG激光照射对人牙周膜成纤维细胞的影响

目的　研究不同输出功率和照射时间设置下脉冲Nd:YAG激光照射对人牙周膜成纤维细胞存活率的影响,并分析其相关性,比较照射前后细胞形态学的变化。方法　将原代培养的人牙周膜成纤维细胞接种于96孔板,细胞按照射时间不同和输出功率不同进行分组并照射。计算细胞的存活率,并比较实验组和对照组细胞存活率的差异,分析输出功率、照射时间与细胞存活率之间的相关性。结果　10 s组、20 s组的0·5 W及1 W设置下细胞存活率与对照组无统计学差异(P>0·05);其余设置下细胞存活率显著降低(P<0·05)。人牙周膜成纤维细胞存活率随照射时间增加而下降的趋势比随输出功率增加而下降的趋势明显。在较低设置下,细胞接受照射后形态未出现明显变化;在较高能量照射后,细胞形态出现变化甚至导致部分细胞死亡。结论　脉冲Nd:YAG激光照射对牙周膜成纤维细胞可造成损害,导致细胞存活率的降低,其中照射时间比输出功率对细胞存活率的影响更明显。

Effect of Pulsed Nd: YAG Laser Irradiation on Periodontal Ligament Fibroblast Cultures

Objective To evaluate the effect of the pulsed Nd:YAG laser irradiation on the survival rate of human periodontal ligament fibroblast(PDLF) at different power and irradiation time settings,and to compare the morphological change of cells before and after irradiation.Methods The cells were cultured and placed into the 96-well tissue culture plates.Cells were divided into groups according to the irradiation time(10 s,20 s,40 s,60 s) and the output energy(0.5 W,1.0 W,1.5 W,2.0 W,2.5 W).After the irradiation,the cell number were counted and the survival rates were calculated.The correlation between the survival rate and irradiation time as well as power output was analyzed.Results No significant reduction of survival rates were found in 10 s group,as well as in 20 s group with 0.5 W,1.0 W setting.The increase of the power output and increase of the irradiation time caused significant reduction of cell survival rate(P<0.05).The irradiation time was more relevant to this reduction than the power output.Conclusion It indicates that the laser irradiation may cause damage to PDLF and decrease the cell survival rate.The irradiation time is more related to this effect than the power output.