ABSTRACT
Objective:To study the related factors of landmarks identification repeatability in the computer monitoring. Methods:Totally 30 lateral cephalograms were selected at random, and the landmarks were identified by 2 orthodontists with the computer monitor twice. The data were obtained and the differences were analyzed. Results:There were differences in inter-operator and intra-operator in their coordination. The operators were similar to each other within a certain range. There were significant differences between the data of the abscissas and ordinate in some landmarks. Conclusion:The repeatability of identified landmarks is closely related to the location of the landmarks, the landmarks identification by human eyes and the quality of the X-rays.