Cone beam computed tomography in mandibular molars referred for apical surgery.

INTRODUCTION The purpose of the present study was to compare conventional intraoral periapical radiographs (PA) with limited cone beam computed tomography (CBCT) for evaluation of mandibular molars prior to apical surgery. The apical extent and homogeneity of the root canal fillings (RCF) as well as the number of root canals were examined. METHODS 38 molars with 75 roots were included in the study. The apical extent and homogeneity of the RCFs as well as the presence of root canal posts or screws were examined on sagittal CBCT slices and on the PAs. The number of root canals was determined on sagittal CBCT slices and the PAs. The mesial and the distal roots were examined separately. RESULTS Considerably more root canals were found on the CBCT slices compared to the PAs. The homogeneity and the extent of the RCFs as well as the presence of root canal posts or screws seem subjectively easier to determine on the PAs. CONCLUSION In mandibular molars, because of the better discrimination of root canal anatomy we recommend a CBCT scan prior to apical surgery.