2009 Volume 22 Issue 4 Pages 492-497
For imaging diagnosis targeting dental implant placement, panoramic radiography, computed tomography (CT), multi-slice computed tomography (multi-slice CT), and recently, cone-beam computed tomography (conebeam CT), are used.
However, the use of CT in routine clinical practice is difficult in some cases for various reasons, and the buccolingual alveolar width may be wide in others.
Therefore, to evaluate the usefulness of panoramic radiography, we investigated the mandibular canal wall-imaging ability of digital radiography, and the dimensional accuracy of panoramic radiography.
In 100 patients for whom mandibular implant placement was planned, 224 molar regions were investigated. The mandibular canal wall-imaging ability of panoramic radiography was investigated, and measurements of the distance between the alveolar crest and upper wall of the mandibular canal were compared with those on double-oblique imaging. Regarding the measurement on double-oblique imaging, one measurement was performed vertically for the slice surface, and the other was bucco-lingually along the direction of the aluminum tube.
The mandibular canal wall-imaging rate on panoramic radiography was 62.5%. Furthermore, there were no differences in the measurement on the double-oblique imaging. Differences in measurements between panoramic radiography and double-oblique imaging were 1.0 mm or less in approximately 50% of the measurements.
In conclusion, although digital panoramic radiography was performed for implant imaging diagnosis, only about 30% of the mandibular molar regions showed clear imaging of the upper wall of the mandibular canal along with a measurement accuracy of within 1 mm, suggesting that the accuracy of panoramic radiography is insufficient.
