Differences in cephalometric measurements: a comparison of digital versus hand-tracing methods

Abstract

The aim of this study was to evaluate the accuracy of cephalometric measurements using computerized tracing of direct digital radiographs in comparison with hand tracing of digital radiographic printouts. Comparisons were made between methods in terms of accuracy of individual measurements as well as evaluation of treatment outcomes. Pre- (T1) and post- (T2) treatment cephalometric digital radiographs of 30 patients were traced using the Vistadent OC 1.1 computer software program (group 1) and manually (group 2) by the same investigator. A total of 26 anatomical landmarks were located and measured. Measurement reproducibility was evaluated by calculating intraclass correlation coefficients, and paired t-tests were used to compare differences in individual measurements and treatment outcomes between methods. Differences greater than 0.05 were considered to be statistically significant. Significant differences were found between the two methods for SNB, Wits appraisal, Cd-A, Cd-Gn, FMA, SN-PP, U1-NA (mm), U1-FH, L1-NB (mm), and Li-E plane. No significant differences were found between the two methods in the measurement of treatment changes. Cephalometric measurements of most parameters were reproducible for both methods. Despite some discrepancies in measured values between hand-tracing and the computerized method, any differences were minimal and clinically acceptable.

Reproducibility of measurements in tablet-assisted, PC-aided, and manual cephalometric analysis

“…9,20 To evaluate reproducibility for each cephalometric parameter, the agreement between the value derived from NemoCeph, that given by SmileCeph, and that measured manually was assessed with the ICC. 4,5,9,20 Agreement was rated as low for an ICC #lower than 0.75. Conversely, an ICC .…”

“…The intention to minimize errors also guided the choice of the landmarks used in this investigation. Following the indications of previous studies, 3,4 the most easily locatable points in analyses featured by both softwares were selected. As the lower incisor apex has often been reported to be affected by the superimposition of other anatomic structures and to have poor reproducibility, 4,24 the measurement of the lower incisor angulation was omitted in the present study.…”

“…Based on similar considerations, measurements involving the point Condylion were not included in the analysis. 4 TABLET-ASSISTED AND PC-AIDED CEPHALOMETRY…”

“…2 Moreover, the quality of digital cephalograms can be improved using digital tools for image enhancement. [3][4][5][6] Additionally, the use of cephalometric tracing softwares on screen-displayed digital images has been considered advantageous in many regards. In computerized cephalometric analysis, once the requested landmarks have been entered, the software automatically calculates distances and angles, thus eliminating errors that may occur in hand tracing when drawing lines with a ruler and measuring angles with a protractor.…”

“…6,9 Earlier studies have assessed the reproducibility of measurements in manual versus computer-aided cephalometric analysis. [3][4][5][6][8][9][10][11][12][13][14][15][16][17][18][19][20] However, as new programs for computerized cephalometry are continuously launched, their accuracy needs to be validated against that of previously marketed softwares and against traditional hand tracing. Lately, a software for digital tracing has been made available as an application for iPad.…”