In vitro comparison of high-resolution USG, CBCT, and direct measurements of periodontal defects

To compare the accuracy of cone-beam CT (CBCT), ultrasonography (USG) and direct measurements in linear dimensions of periodontal defects on the buccal alveolar surfaces of mandibular sheep teeth.

A total of 88 defects were artificially created, including dehiscence, fenestration, grade I and II endodontic-periodontal defects. Two observers performed measurements twice. Maximum length, depth, and width of the defects were measured with all 3 methods. Manual measurements were accepted as the gold standard. Intraclass correlation coefficients (ICC) were calculated. The mean value of the measurements, the bias, the SD of the differences, and the limits of agreement were estimated. Statistical significance was set at P < .05.

Intra- and inter-observer reliability was excellent, suggesting ICCs 0.988-1 and 0.981-1, respectively. The highest CCs were obtained from depth measurements, while the lowest CCs were obtained from length measurements. Although the differences were scattered around the bias. The estimated bias values for USG and CBCT were 0.18 (0.153-0.21) (P < .001) and 0.091 (0.079-0.102) (P < .001), respectively. Observers recorded measurements which were slightly underestimated with both techniques utilized.

Observers measured periodontal defects with clinically acceptable underestimations by using CBCT and USG.

It is important to compare different innovative imaging modalities and gauge their efficiency in the measurement of various types of periodontal defects in terms of treatment planning, prognosis, and follow up of those cases.