[A comparison of three cephalometric analysis on the evaluation of orthodontic treatment].

Objective: To analyze the reliability of different cephalometric superimposition methods for evaluation of orthodontic treatment.

Methods: The material consisted of fourteen pairs of cephalograms obtained before and after Herbst treatment. Each pair of the cephalograms were traced, superimposed by means of the three different superimposition methods three times each. A reference grid was used to quantitatively evaluate the sagittal dental and skeletal changes.

Results: (1) There was no statistically significant difference between the repeated measurements in the three methods respectively, i.e. all the three methods were reliable. (2) There was no significant difference among the three superimposition methods to evaluate the sagittal skeletal and dental changes. (3) Comparing the coefficient of reliability, none of the three methods was suitable for the individual assessment, and Pancherz' method only was acceptable for assessment of patients in groups.

Conclusion: The three methods have their own characteristic. The Pancherz's method is comparatively direct and effective on quantitative evaluation of orthodontic treatment.