上颌前磨牙根管壁的扫描电镜观察

SEM study of the root canal wall of upper premolars

目的研究恒牙根管壁的微观结构,为牙髓治疗提供参考。方法将10个离体上颌前磨牙用金钢砂片及砂轮剖开,52.5g/L次氯酸钠溶液浸泡24h去除牙髓组织。经过脱水、喷金处理,扫描电镜下观察根管内壁的微观结构。结果根管壁牙本质小管口的密度在根颈1/3处为4～5万个/cm2,根尖1/3处为1～2万个/cm2,扫描电镜下观察到钙球、侧副根管开口及根尖部的微观结构。结论根管壁在根管的不同部位具有不同的微观形态学特点;越近根尖,其形态和结构越为复杂。

AIM:To observe the morphology of the internal dentin wall of the root canals by scanning electronic microscopy(SEM) and provide anatomical reference for endodontic treatment.METHODS:10 upper premolars were selected in this study.After section by carborundum wheel,the dentin wall of the root canals were exposed.The organic tissue in the root canals was dissolved in 52.5 g/L NaOCl solution.Then the specimens were treated by dessication and spray-gold.SEM was used to study the microstructure of the root canal wall.RESULTS:The numerical density of the orifices of dentinal tubules was 40～50 thousands/cm2 on the dentin wall of neck 1/3 part of the root canal,and 10～20 thousands/cm2 on the dentin wall of the apical 1/3 part.The morphology of the calcospherites,orifices of accessory canals and configuration of the apex were described in detail.CONCLUSION:The morphological characteristic of root canal wall varied at different parts of the root canals,and the microstructures were more complex near the root apex. [