Objective: Microstructural changes in dentin carious lesions were investigated using a 3D laser scanning microscope, which has a morphological theoretical foundation in the further study of clinical caries disease prevention and treatments.
Methods: Six fresh extracted caries molars were prepared into cross-section specimens. The sections were examined by 3D and laser measuring morphology.
Results: Zones were identified in the lesions on the basis of their optical appearance. Two zones were identified in the lesions on the basis of their laser appearance. The microstructure showed that the tubular was partly closed in transparent dentin; peritubular and intertubular dentin were reduced in the zone of demineralization; peritubular and intertubular dentin were damaged and fused; a beaded sample and oval lesions formed in the zone of bacterial invasion; and abnormal dentin structure was present in the zone of destruction on the basis of their laser appearance. Four zones were iden-tified in the lesions according to their colors, as determined from their 3D appearance.
Conclusions: 3D laser scanning micros-cope may be a powerful, accessible, and non-destructive technique, as it identified the lesion and tubular zones, as well as peritubular and intertubular dentin in the four zones' lesions. The microstructure of dentin caries lesions may have significant merit in the evaluation of clinical prevention and treatment.
目的 通过3D激光扫描显微镜观察牙本质龋的微结构，为临床上龋病的防治及相关研究提供形态学理论依据。方法 收集6颗新鲜拔除的有龋坏的第三磨牙，均制备成横剖面标本，在3D激光扫描显微镜下进行光学、激光彩色及3D形貌图的观察。结果 在样本整体结构中，光镜下可见病变组织的轮廓，激光彩色镜下较清晰分辨两层牙本质病变；在微结构中，激光彩色图下可以观察到透明层牙本质小管部分闭合，脱矿层管周和管间牙本质数目较少，细菌侵入层管周和管间牙本质均破坏，相邻小管融合，呈串珠样和椭圆形病灶，坏死崩解层无正常牙本质结构。3D形貌图下可根据颜色的不同观察到四层结构。结论 3D激光扫描显微镜能够分辨牙本质龋的两层病变组织结构，观察到牙本质四层结构中牙本质小管、管周、管间牙本质的不同改变，是观察牙本质微结构的有力工具。同时牙本质龋微结构的形态对临床上龋病的防治及相关研究具有理论指导意义。.
Keywords: 3D laser scanning microscope; dentin caries; microstructure; tubular.