OBJECTIVE: The purpose of this study was to assess the influence of magnification and
superimposition of structures on CBCT-generated lateral cephalometric radiographs
(LCR) using different segments of the cranium. METHODS: CBCT scans of 10 patients were selected. Four LCR were generated using Dolphin
Imaging(r) software: full-face, right side, left side and center of
the head. A total of 40 images were imported into Radiocef Studio 2(r),
and the angles of the most common cephalometric analyses were traced by the same
observer twice and within a 10-day interval. Statistical analyses included
intraexaminer agreement and comparison between methods by means of intraclass
correlation coefficient (ICC) and Bland-Altman agreement tests. RESULTS: Intraexaminer agreement of the angles assessed by ICC was excellent (> 0.90)
for 83% of measurements, good (between 0.75 and 0.90) for 15%, and moderate
(between 0.50 and 0.75) for 2% of measurements. The comparison between methods by
ICC was excellent for 68% of measurements, good for 26%, and moderate for 6%.
Variables presenting wider confidence intervals (> 6o) in the
Bland-Altman tests, in intraexaminer assessment, were: mandibular incisor angle,
maxillary incisor angle, and occlusal plane angle. And in comparison methods the
variables with wider confidence interval were: mandibular incisor, maxillary
incisor, GoGn, occlusal plane angle, Frankfort horizontal plane (FHP), and CoA.
CONCLUSION: Superimposition of structures seemed to influence the results more than
magnification, and neither one of them significantly influenced the measurements.
Considerable individual variability may occur, especially for mandibular and
maxillary incisors, FHP and occlusal plane.