Pallarés A, Faus V, Glickman G N
Department of Pathology and Dental Therapeutics, Faculty of Odontology, University of Valencia, Spain.
Int Endod J. 1995 Sep;28(5):266-9. doi: 10.1111/j.1365-2591.1995.tb00312.x.
The objective of this study was to compare the adaptation of mechanically softened gutta-percha to the root canal wall in the presence and absence of smear layer. The root canals of 20 freshly extracted human maxillary incisors were cleaned and shaped. Prior to obturation, 10 root canals were irrigated with 20 ml of 50% citric acid followed by 20 ml of 5.25% sodium hypochlorite. All canals were obturated with mechanical compaction of gutta-percha and AH-26 sealer. After 72 h, each tooth was fractured in half. Scanning electron microscopy demonstrated that the sealer had formed a continuous layer in contact with the canal walls, becoming progressively thinner towards the apex. The sealer penetrated into the dentinal tubules along with projections of gutta-percha only in those teeth without smear layer.
本研究的目的是比较在有和没有玷污层的情况下，机械软化牙胶对根管壁的适应性。选取20颗新鲜拔除的人上颌中切牙，对其根管进行清理和预备。在充填前，10个根管先用20 ml 50%的柠檬酸冲洗，然后用20 ml 5.25%的次氯酸钠冲洗。所有根管均采用牙胶机械加压充填和AH-26封闭剂。72小时后，将每颗牙齿沿中线劈裂为两半。扫描电子显微镜显示，封闭剂与根管壁形成了连续的一层，向根尖方向逐渐变薄。只有在没有玷污层的牙齿中，封闭剂才会随着牙胶的突起一起渗入牙本质小管。
