RESUMO
Objective @# To investigate the effects of different root canal filling stop on quality of root canal filling and apical sealing in root canals obturated with GuttaFlow. @* Methods@#60 teeth were randomly divided into three groups, using different root canal filling stops to shape the root canals with MTwo (25/06) file. All root canals were obturated with Gutta Flow, and the overfilling of the root canals were recorded and evaluated by X-ray. And the apical microleakage of teeth was evaluated by transparent teeth technique.@*Results@#The roots were prepared with MTwo (25/06) as master apical file, the overfilling rate of the root canals in root canal filling stop was higher as the distance from the apex was shorter, but there was no significant difference. The under-filling rate of the root canals in root canal filling stop was higher as the distance from the apex was longer. And the under-filled root canals in root canal filling stop 0.5 mm from the apex showed a statistically significant difference with 2 mm. The mean dyeing penetration length in 0.5 mm and 1 mm group was significantly shorter than 2 mm group. @*Conclusion @#A suitable root canal filling stop could improve the quality of root canal filling in root canals obturated with GuttaFlow.