transportation and centering ability of neoniti and protaper instruments; a cbct assessment

introduction: transportation is an important iatrogenic endodontic error which might cause failure. this study evaluated the canal transportation caused by neoniti and protaper instruments, using cone-beam computed tomography (cbct) cross sections. methods and materials: this in vitro experimental study was performed on 40 mesiobuccal roots of maxillary first molars. the teeth were scanned with cbct. they were randomly divided into 2 groups ( n =20) that were prepared using either neoniti or protaper files. an endodontist prepared the canal according to the manufacturer’s guidelines. prepared canals were re-scanned. the pre-instrumentation and post-instrumentation cbct volumes were sectioned at 1 to 9-mm distances from the apex. the extent of canal dentine removal in mesial and distal directions were measured in each cross-section. canal transportation and instrument centering ability were estimated based on the extents of root wall removal and were compared in both groups. results: the groups were rather similar in terms of transportation and centering ability ( p >0.05). however, canal preparation on mesial and distal walls was statistically significantly less in the neoniti group, at most cross-sections. transportation of both groups was not significantly different ( p >0.05). centering ability of both instruments was not significantly different ( p >0.05). conclusion: neoniti and protaper instruments might have proper centering ability and minimum transportations. both instruments might cause similar extents of transportation and centering abilities.