<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>This study was designed to investigate the factors affecting linear distortion in orthopantomography. A test model was constructed with metallic rods positioned to simulate maxillary teeth from the first permanent molar to the lateral incisor. In addition to examining the effects of varying the tilts of the test rods in a mesio-distal or bucco-palatal direction, spatial position changes (sagittal displacement, transverse displacement and horizontal rotation) of the test model were evaluated by determining the magnification changes in the width and length of the test rods. Results showed that significant errors occurred with all variations in magnification when test rods were inclined buccopalatally (<italic>p</italic> &lt; 0.001) at or exceeding 5 degrees relative to the true perpendicular, and for spatial positioning errors (<italic>p</italic> &lt; 0.05) at or exceeding ±5 degrees and ±5 mm. Bucco-palatally inclined objects in the lateral incisor-canine region were particularly susceptible to large changes in horizontal magnification. Linear measurements and clinical assessments from panoramic radiographs should therefore be undertaken cautiously. To minimise errors in orthopantomography, it is important to position the patient in the focal trough precisely according to the manufacturer’s specification.</p>
</abstract>

This study was designed to investigate the factors affecting linear distortion in orthopantomography. A test model was constructed with metallic rods positioned to simulate maxillary teeth from the first permanent molar to the lateral incisor. In addition to examining the effects of varying the tilts of the test rods in a mesio-distal or bucco-palatal direction, spatial position changes (sagittal displacement, transverse displacement and horizontal rotation) of the test model were evaluated by determining the magnification changes in the width and length of the test rods. Results showed that significant errors occurred with all variations in magnification when test rods were inclined buccopalatally (p < 0.001) at or exceeding 5 degrees relative to the true perpendicular, and for spatial positioning errors (p < 0.05) at or exceeding ±5 degrees and ±5 mm. Bucco-palatally inclined objects in the lateral incisor-canine region were particularly susceptible to large changes in horizontal magnification. Linear measurements and clinical assessments from panoramic radiographs should therefore be undertaken cautiously. To minimise errors in orthopantomography, it is important to position the patient in the focal trough precisely according to the manufacturer’s specification.

Distortions in panoramic radiographs

Australasian Orthodontic Journal

This work is licensed under the Creative Commons Attribution 4.0 International License.

{"article-title":"Distortions in panoramic radiographs"}

This study was designed to investigate the factors affecting linear distortion in orthopantomography. A test model was constructed with metallic rods...

Distortions in panoramic radiographs

Published Online: Dec 15, 2023

Page range: 92 - 98

Received: Jun 01, 2002

Accepted: Sep 01, 2002

DOI: https://doi.org/10.2478/aoj-2002-0014

© 2002 D.K.L. Yeo et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.