Ability of Cone-beam Computed Tomography to Detect Periapical Lesions That Were Not Detected by Periapical Radiography: A Retrospective Assessment According to Tooth Group.

INTRODUCTION: The detection of periapical lesions by periapical radiography (PR) can be hampered by structural noise, the impact of which differs among tooth groups. The aim of this study was to investigate the ability of cone-beam computed tomographic (CBCT) imaging to detect periapical lesions that could not be detected with PR according to tooth group. METHODS: This study retrospectively evaluated teeth that (1) had previously undergone root canal treatment (178 teeth from 86 patients), (2) had coincidentally been located within the field of view of CBCT scans performed for endodontic reasons, and (3) had also been examined with PR. The teeth of interest for the CBCT examinations were excluded to avoid sampling bias. Two dentists evaluated both the CBCT and PR images for periapical lesions. The McNemar test was used to compare the ability of CBCT imaging and PR to identify periapical lesions (alpha = 0.05). RESULTS: The overall periapical lesion detection rates of PR and CBCT imaging were 31.5% and 52.2%, respectively (P < .0001). The ability of CBCT imaging to identify periapical lesions that were not detected by PR was statistically significant for the maxillary incisors/canines (P < .0001) and maxillary molars (P < .005). CONCLUSIONS: Within the limitations of this investigation, it can be concluded that CBCT imaging is effective at detecting periapical lesions that cannot be detected on PR, particularly in the maxillary incisors/canines and molars. Our findings suggest that the influence of structural noise in the maxillary anterior region and maxillary posterior region should not be overlooked during the interpretation of PR images.