Accuracy of different measurement methods for lateral cephalograms

Abstract

Orthodontists often measure cephalograms with rulers or scan them into computers during treatment planning. We examined the accuracy of several measurement methods. Using cephalograms of adult males with normal occlusion. Three methods were considered: pencil traces measured by rulers, pencil traces input to a computer using a scanner, and cephalograms directly input to a computer. We calculated significance at the 95% confidence level, and applied the F-test for variance.
The 95% confidence level measurements were greatest for the pencil traces (1.0 mm and 0.5 degrees). These values were smallest for the group where the cephalograms were directly input to the computer (about 0.2 mm and 0.2 degrees). There was a significant difference at the 1% confidence level for differences between the group where measurements were by direct scanning into the computer when compared with the other two groups. We concluded that in order to increase accuracy, it is necessary to evaluate the cephalograms by direct scanning into a computer.Shika Igaku(J Osaka Odontol Soc) 2003 Dec; 66(4): 325-330.