The aim of this study was to compare the success after endodontic treatment performed with or
without continuous ultrasonic irrigation.
70 Mandibular molars with diagnosis of pulpal necrosis and with periapical radiolucency were
randomly assigned into two treatment groups- continuous ultrasonic irrigation (CUI) and
syringe irrigation (SI). Standard nonsurgical endodontic treatment was performed on both
groups under rubber dam isolation with 0.02 taper ISO stainless steel hand files using step
back technique. In both groups, 5 ml of 5.25% sodium hypochlorite was used as irrigant after
each instrument. After root canal instrumentation, canals were irrigated with 5 ml of 17%
EDTA solution for 1 minute. In SI group, canals were flushed with 15ml of 5.25% sodium
hypochlorite using a 27 gauge needle while final irrigant was delivered using a continuous
ultrasonic irrigation device in CUI group. An inter-appointment dressing of calcium hydroxide
was given and patient was recalled after one week and canals were obturated with the Gutta
Percha. Immediate postoperative radiograph was then taken, followed by radiographs at 3, 6, 9
and 12 months.