Comparison of mesiodistal measurements of single implant sites on panoramic images generated at different horizontal levels: A cone beam CT study

Background: This study aimed to compare mesiodistal measurements of single implant sites on cone beam CT (CBCT) panoramic images generated at different horizontal levels. Materials and Methods: CBCT images for 101 single implant sites of 66 patients referred for pre-surgical radiographic dental implant planning were selected for the study. In addition to automatic horizontal level determined by the CBCT software, panoramic images were generated at three different horizontal levels (central incisal edges, crest of the ridge at the implant site, and apices of central incisors) at jaw of interest and mesiodistal measurements were performed by two observers. The measurements were averaged and differences in the means were compared using repeated measures analysis and Bonferroni multiple comparison test. Results: The mean values of mesiodistal measurements at the automatic horizontal level and apices of central incisors level were significantly lower than the mean values at central incisal edges level and crest of the ridge level (8.09, 8.02, 8.54, 8.51 mm respectively). Conclusions: CBCT Panoramic images generated at different horizontal levels can yield different mesiodistal measurements of single implant sites, and further studies with a gold standard need to be conducted to determine the horizontal level of choice.