The evaluation of 20 MHz ultrasonography, computed tomography scans as compared to direct microscopy for periodontal system assessment.

AIM To identify by ultrasonography (DermaScan C, Cortex Technology1) the reference points necessary to monitor the horizontal bone resorbtion and to assess the accuracy of the measurements by comparing with Cone Beam Computed Tomography images, having direct microscopic section measurements as a gold standard. MATERIAL AND METHODS We performed the examinations on the lingual side of the alveolar bone of 4 pig mandibles. We tried to identify the enamel-cementum junction, the root, the periodontal space at the appearance of the tooth from the alveolar bone, the edge of cortical bone at its coronary limit (in order to assess the horizontal bone resorption). We measured the distance between the enamel-cementum junction and the coronal edge of cortical bone. RESULTS There was a strong positive correlation between the alveolar bone level measured with the 3 techniques. Correlation parametric R2 tests were statistically significant for DermaScan measurements compared to microscopy ones (p<0.0001). Linear regression showed statistically significant correlations for alveolar bone level measurements made by CBCT compared to microscopy (p<0.05). CONCLUSIONS The cementum-enamel junction may be identified on ultrasonic images with high accuracy according to the tooth anatomical convexities, therefore this method can be used for monitoring the periodontium.