Er:YAG激光照射离体牙釉质后表面形态和髓腔温度的观察

The observation of surface morphology of enamal and temperature of dental pulp cavity in vitro after irradiated by Er:YAG laser

目的观察不同能量和时间作用下Er:YAG激光照射人离体牙釉质后表面形态和髓腔温度的变化。方法临床收集24颗离体牙,制备成96个实验样本,按不同处理方法分为A、B两组,分别照射10、20 s,每组再分为6个亚组,选择超短脉冲20 Hz,分别采用1、2、3、4、5、6 W的能量对每个亚组样本的釉质进行照射,用数字式温度计记录髓腔温度的变化,扫描电子显微镜(SEM)下观察样本釉质形态的变化。结果随着照射时间的延长和能量的增加,髓腔温度有上升的趋势;SEM观察A、B两组的釉质形态均有改变,但两组均未发现熔融和碳化现象。结论在Er:YAG激光一定能量的照射下,釉质的形态和髓腔温度产生一定的变化,但是未出现熔融和碳化现象,为临床龋齿的治疗提供了依据。

Objective To observe the changes of surface morphology and temperature of dental pulp cavity in vitro after irradiated by Er：YAG laser with different energy and irradiation time.Methods All of the 96 samples from 24 teeth in vitro were collected from dental clinical departments then divided into two groups（group A and group B） randomly.We chose the energy of 20 Hz,and 1,2,3,4,5,6 W to treat the samples in group A and group B and the irradiation time was 10 s or 20 s.We recorded the temperature changes of dental pulp cavity by digital thermometer and observe the morphology of tooth enamel by scanning electron microscope（SEM）.Results With the extension of irradiation time and increasing of energy,the temperatures of dental pulp cavity were significantly increased after the treatment of Er：YAG laser.The two groups of tooth enamel surface morphology were changed after irradiated by Er：YAG laser with different energy and irradiation time.However,there was no melting and carbonation on the surface of tooth enamel after the treatment of Er：YAG laser in two groups.Conclusion The temperatures of dental pulp ca-vity were increased after irradiated by increasing laser energy density fom 1 W to 6 W.No melting or carbonized phe-nomenon was found in enamel within the energy of 1 W to 6 W.All the data would provide evidences for clinical treatment of cavity.