A Comparison Of Panoramic Radiography And Spiral CT For Alveolar Measurement

Objective To compare the results between panoramic radiography(OP), spiral CT(SCT) and direct measurement of the alveoli to provide preoperative guidance for insertion of the dental implant.Materials and Methods 3 human edentulous skulls were examined with OP and SCT(axial and coronal),each marked with 12 radiopaque markers. Then the j aws were sawed at markers' sites in coronal plane. Height and/or width of the alveoli in images and specimens were measured respectively.3D reconstruction was made with computer.Results Both OP and Spiral CT somewhat distorted images,OP(22.39%)> SCT(5.28%) ,P<0.0001.Differences between images and real measurement were statistically significant. The Wilcoxon-test of between alveolar height' s and marker' s magnification in OP showed non-significant difference (P>0.5) , and correlation coefficient(r)=0.8335,demonstrating good positive correlation.Conclusion OP unit' s inherent magnification can' t but marker' s can be used to evaluate height of the alveoli.SCT can showcross-sectional images (buccal-lingual) and is more accurate than OP. It may be most valuable imaging modality for preoperative evaluation of height of the alveoli.