Periodontal probing in comparison to diagnosis by CT-scan

To compare clinical periodontal probing and the corresponding CT-evaluation of the loss of bone.

639 measurement sites were studied on 95 periodontal sites. The measured length was the distance between the cemento-enamel junction (CEJ) and the pocket base on probing and the bone base of the pocket on the CT-analysis. Additionally, a comparison of the diagnostic potential of both methods regarding the furcation involvement was made.

Clinical probing depths showed a mean value of 2.6+/-2.0 mm, while the CT-measurements exhibited a figure of 4.2+/-2.3 mm. In 49.5% of the measured sites, the difference between clinical and CT-measurement was 2mm or higher. The greatest differences between the measured values were found on the buccal and lingual sites (P=0.0004). The narrower the vertical bone defects in the CT (angle in coronal direction), the greater were the differences between the clinical probing depths and the measurements carried out on the CT (P=0.02). Clinically, in 31% of the cases the furcation involvement was underestimated or not identified at all.

Computed tomography imaging techniques could be beneficial in the field of periodontal diagnosis. The results underscore the higher accuracy of the CT-technique, compared with clinical probing, while assessing periodontal breakdown and its marked superiority in the diagnosis of furcation areas, compared to the clinical examinations performed.