Linear and angular measurements from plain film cephalometry, 3DCeph, and CBCT / Medidas angulares e lineares em cefalometria em telerradiografias de norma lateral, cefalometria tridimensional, e em tomografias de feixe em cone

ABSTRACT

The advent of cone beam computed tomography (CBCT) in orthodontics raises the question of how it compares with existing diagnostic tools in providing useful quantitative measures. This study compared linear and angular measurements from craniometry (Cranio), plain film cephalometry (Ceph), three-dimensional cephalometry (3DCeph), and CBCT. Methods: Sixteen linear and fourteen angular measurements were taken using Cranio, Ceph, 3DCeph, and CBCT in 6”, 9”, and 12” field of views (FOV) from five dry skulls. Cranio values defined the “gold standard” for linear measurements, and Ceph values the angular. Paired t-tests and correlations were used for comparison. Results: For linear measurements, Ceph had the most significant differences, followed by 3DCeph and CBCT. All had high (r>0.75) correlations. Average discrepancies were 4.18 mm for Ceph, 1.32 mm for 3DCeph, and less than 1 mm for CBCT in all three FOVs. For angular measurements, CBCT(9) and CBCT(6) were not considered due to incompleteness. Cranio had 6 significant differences, CBCT had 5, and 3DCeph had 2. Cranio and CBCT had low correlations for FMA and FMIA. Average discrepancies were 2.7O for Cranio, 2.1O for CBCT, and 1.8O for 3DCeph. Conclusions: CBCT compared favorably with craniometry for linear measurements, but not with traditional cephalometrics for angular.