Sixteen fresh extracted human teeth paired according to their anatomic locations,were divided into two groups at random.The root canais of the teeth in Group 1 were preparedwith an ultrasonic unit and those of Group 2...Sixteen fresh extracted human teeth paired according to their anatomic locations,were divided into two groups at random.The root canais of the teeth in Group 1 were preparedwith an ultrasonic unit and those of Group 2 with hand instruments.Then,the specimens wereobserved under a scanning electron microscope and their pnotographs were taken.Blindevaluation of cleanness was performed for each canal.Statistical dnalysis of the data indicatesthat the canal walls were cleaner in Group 1 than in Group 2 and that the ultrasonic preparationtook less time.展开更多
文摘Sixteen fresh extracted human teeth paired according to their anatomic locations,were divided into two groups at random.The root canais of the teeth in Group 1 were preparedwith an ultrasonic unit and those of Group 2 with hand instruments.Then,the specimens wereobserved under a scanning electron microscope and their pnotographs were taken.Blindevaluation of cleanness was performed for each canal.Statistical dnalysis of the data indicatesthat the canal walls were cleaner in Group 1 than in Group 2 and that the ultrasonic preparationtook less time.