The accuracy of manual and digital measurements on conventional lateral cephalograms

The study on the accuracy of manual and digital measurements was conducted on conventional lateral cephalograms of 66 randomly selected patients with malocclusion from the Clinical Orthodontics at the Ambulatory Clinic of the “St. Spiridon” University Emergency Hospital, Iasi, Romania. Forty-six linear and angular measurements were performed with Steiner, Tweed and Jarabak analyses. The manual measurements were conducted with a ruler and a protractor, the digital ones with Onyx CephTM (Onyx CEPH 2.7.18 (174) Image Instruments GmbH, Chemnitz, Germany). The statistical analyses were performed in SPSS, version 20.0. The results presented different mean values of measurements calculated with two analyses, being statistically significant (p<;0.05) for 30 measurements. Some values were pathological, others have changed the diagnosis of skeletal class. The most important differences were found in the metric measurements through Jarabak analysis. The causes of these differences were mainly due to human error in both methods of cephalometric analysis.