铒,铬:钇钪镓石榴石激光切割牙体硬组织效果的扫描电子显微镜观察

目的　对铒,铬:钇钪镓石榴石(Er,Cr:YSGG)激光切割的牙体硬组织进行扫描电子显微镜观察,探讨此激光在不同能量参数下进行窝洞制备的效果,以便为其在临床上的应用与推广提供实验依据。方法　将12颗前磨牙随机分3组,分别用高速裂钻、4W Er,Cr:YSGG激光及6W Er,Cr:YSGG激光处理后,将牙齿沿横向、纵向剖开,常规制片,扫描电镜观察牙体硬组织表面结构形态。结果　钻切组:切面较平,但有明显裂纹;表面覆盖致密的玷污层。激光组:切面不平,呈鱼鳞状改变,无玷污层;牙本质切面小管清晰,无炭化及热损伤改变。与4 W功率相比,6 W时表面更为粗糙。结论　应用Er,Cr:YSGG激光切割后的牙体,其表面结构有助于修复材料与牙体组织间的粘接。建议临床应用时采用高能量参数切割牙釉质,低能量参数切割牙本质。

A Scanning Electron Microscopy Study on Morphological Changes of Er,Cr:YSGG Laser-Cutted Dental Hard Tissue

Objective\ The purpose of this study was to evaluate the morphological changes of Er,Cr:YSGG laser irradiated dental hard tissues by scanning electron microscopy (SEM).Methods\ 12 freshly extracted premolars were treated with fissure bur, Er,Cr:YSGG laser at 4 watt, Er,Cr:YSGG laser at 6 watt, respectively, and then bisected transversally and longitudinally. The tooth slice were prepared with conventional methods and observed by SEM.Results\ Compared with fissure bur, laser treatment resulted in a rather scaly and rough surface. The sections were free of smear layer, with open dentinal tubules. No carbonization and thermal damages were observed. The laser at 6 watt appeared rougher than at 4 watt, occasionally caused micro_cracks.Conclusion\ The utilizing of Er,Cr:YSGG laser can contribute to enhance the bond strength between restorative materials and dental hard tissues. It suggests that higher energy could be applied in cutting enamel, whereas the lower energy in dentin.