Evaluation of the precision of dimensional measurements of the mandible on panoramic radiographs

摘要

Objectives: The purpose of this study was to assess the accuracy of panoramic radiography in measuring the linear dimensions. Materials and methods: Various vertical, horizontal, oblique and angular parameters were denoted by metal markers and were measured on 30 dry mandibles with the use of calipers. The same mandibles were then positioned on panoramic machine, EC Proline and radiographic images of them were made. Measurements of the same distances were made on panoramic images and then compared with the measurements on the dry mandible. All the results were statistically analyzed. Results: The measurements made on dry mandibles as well as on the panoramic images of the same revealed that they were statistically significant. The results of the measurements showed that the calculated magnification indices were lower than the manufacturer's magnification index for the vertical, horizontal, oblique and angular measurements so long as the distance measured is on only one side of the mandible, whereas the calculated magnification Indices for the vertical, horizontal, oblique distances which traversed the midline of the mandible, were greatly enlarged than the manufacturers magnification index. Conclusion: It was concluded that it is possible to use panoramic radiography for linear measurements of vertical, horizontal or oblique variables provided it is on only one side of the mandible.