Comparison of Panoramic Radiography and Cone-Beam Computed Tomography for the Detection of Tonsilloliths

A tonsillolith is a concretion of the tonsillar crypt. The aim of this retrospective study was to compare panoramic radiography (PR) and cone-beam computed tomography (CBCT) for the detection of tonsilloliths.

The CBCT images of 527 patients with maxillofacial volume were evaluated retrospectively. Of these, 175 patients (81 females, 94 males; mean age 51.05 years) had unilateral or bilateral tonsilloliths. In total, 151 of them (67 females, 84 males; mean age, 51.03 years) had PR images performed in the same period and were included in the study. The PR images were examined to ascertain whether known tonsilloliths (from CBCT images) could be detected. The location (unilateral; left or right and bilateral), size, and number of the tonsilloliths were examined on both CBCT and PR images. Descriptive analysis, Spearman's rho correlation coefficient, and χ2 tests were used for the statistical analysis.

The detection rate of tonsillolith was 33.2% on CBCT images. Only 51.4% of the tonsilloliths detected on CBCT were evaluated by PR; the correlation between CBCT and PR was found to be significant (Spearman's r = 0.399, p = 0.000). PR was not adequate to detect tonsilloliths 1 mm or smaller in size. All the calcifications larger than 5 mm were detected on PR images.

The results of this study showed that more than half of the tonsilloliths observed in CBCT were also detected in PR. Tonsilloliths larger than 2 mm were more likely to be detected on PR images.