Retrospective radiologic study

CBCT images were examined in axial, sagittal, and coronal slices to investigate the presence of antroliths. The age and sex information of the detected cases were recorded.

Each sinus cavity exhibiting antroliths was evaluated for distribution and location as follows: (1) unilateral or bilateral, (2) single or multiple, (3) tooth extraction/root canal treatment/residual root fragment/implant/periodontal disease and/or periapical lesion (any dental cause of sinus inflammation), (4) premolar or molar region, and (5) sinus floor, lateral wall, or medial wall.

the detected antroliths were categorized according to the classification of Cho et al. In this classification made according to the sizes of antroliths, Punctate = ≤3 mm in both height and width, Linear = ≤3 mm and more than treble in width, and Amorphous = >3 mm in both width and height.

Additionally, the locations of the openings of the maxillary sinus ostiums were evaluated, and mucosal thickening, if any, was measured. Mucosal thickness measurements were made on coronal slices using NewTom's NNT viewer measuring tool. Similar to Chen et al., the sinus membrane thickness was measured perpendicular to the bone wall, from the maximum thickest region. Similar to Chen et al.'s classification of sinus membrane thickness measurements, which used Block and Dostoury's classification, the mucosal thickness was classified into three subgroups: membrane thicknesses <2 mm, 2-5 mm, and >5 mm. Also, similar to the article by Cho et al., the degree of inflammation in the maxillary sinus was

3D reconstruction and volume measurements of antroliths were performed using the ITK SNAP software (free software under the GNU General Public License developed by the National Institutes of Health, the US National Institute of Biomedical Imaging and Bioenergy needs, the US National Library of Medicine, the Universities of Pennsylvania and North Carolina, and an independent group of developers).