半导体激光与ND:YAP激光在牙齿美白中的应用效果分析

Application effect of semiconductor laser and ND: YAP laser in tooth whitening

目的:通过扫描电镜观察冷光美白,半导体激光美白,ND:YAP激光美白术后牙釉质表面微结构变化情况。方法:选取因正畸拔除的新鲜前磨牙,随机分为正常组,冷光美白组,半导体激光组和ND:YAP激光组。冷光组以35%过氧化氢美白凝胶涂布牙面,冷光照射15 min,共3次;半导体激光组用35%过氧化氢涂布牙面,1.5 W,20 Hz,1/2波形照射15 s,重复3~4次;ND:YAP激光组用35%过氧化氢涂布牙面,5 W,30 Hz,G模式照射牙面15 s,重复3~4次。记录各组美白前后色阶变化情况并分别置于扫描电镜下观察。结果:三实验组美白术后色阶变化无显著统计学差异(P>0.05)。正常牙釉质表面光滑无凹陷;半导体激光组釉质表面见不规则裂缝及再矿化结晶;ND:YAP激光美白组牙本质小管被侵蚀呈熔融状态,局部有弹坑样深凹陷形成;冷光美白组牙齿表面有不同程度大小的微孔凹陷,呈蚀刻样改变。结论:三种美白技术都可以达到显著的美白效果,半导体激光和ND:YAP激光操作时间较短,对牙釉质表面的损伤较冷光美白小,同时半导体激光对美白剂的高效处理方式,对牙釉质表面微结构损伤最小。

Objective:Observe the microstructure of tooth enamel after cold light whitening,semiconductor laser whitening and ND:YAP laser whitening under scanning electron microscopy(sem).Methods:Orthodontic extraction fresh premolar teeth were chosen and divided into normal group,cold light group,semiconductor laser group,ND:YAP laser group.The cold light group was coated with 35%hydrogen peroxide enamel and then radiated with cold light for 15 minutes for 3 times;the semiconductor laser group was coated with 35%hydrogen peroxide enamel and irradiated with 1/2 wave of 1.5 W/20 Hz,15 s,repeated 3~4 times;ND:YAP laser group was coated with 35%hydrogen peroxide enamel irradiated with wave of 5 W/30 Hz,G mode 15 s,repeated 3~4 times.The color changes of each group were observed under the scanning electron microscope and recorded.Results:There was no statistically significant difference in the change of color among the three experimental groups(P>0.05).The surface of normal tooth enamel was smooth;the enamel surface of semiconductor laser group had irregular fracture and remineralization crystallization;the dentine tube of ND:YAP laser group had been eroded into molten state and deep depressions formed locally;the surface of cold light group had etching changes with microporous dents.Conclusion:All the whitening techniques can achieve satisfactory results.Semiconductor laser and ND:YAP laser led to less damage of tooth enamel with shorter operation time.At the same time the most effective treatment of semiconductor laser led tominimal damage of the enamel surface.