Follow-up of idiopathic osteosclerosis on cone-beam computed tomography: a retrospective longitudinal study

This study aimed to investigate the cone-beam computed tomography (CBCT) follow-up of adult patients with asymptomatic, incidentally encountered idiopathic osteosclerosis (IO) to demonstrate its natural course. Retrospectively, 37 patients (mean age, 40.5 years; 19 females and 18 males) with mandibular IO were included, based upon clinico-radiological features. Inclusion criteria were a baseline and at least one follow-up CBCT scan after 12 months or later, no periapical inflammatory lesion, and no previous endodontic or surgical treatment in the respective dentate region. Changes of maximum axial and cranio-caudal diameter and morphology (tooth relationship, lesional shape, radiodensity, endosteum and mandibular canal relationship, root resorption) were evaluated in 45 lesions and descriptively analyzed. The interreader agreement was calculated for diameter and morphological evaluation by intraclass correlation coefficient (ICC) and weighted κ statistics, respectively. The results showed that none of the lesions changed in diameter nor in morphology within the respective follow-up (mean, 19.0 months, maximum 96.0 months). Overall, there was high interreader agreement (up to ICC = 0.854, and weighted κ = 1). In conclusion, on CBCT, IO morphometrics and morphology may naturally remain unchanged in asymptomatic adults, even after up to eight years of follow-up. Consequently, once the diagnosis of IO has been established, CBCT follow-up might not be justified to prevent imaging overuse, which is associated with an excess of ionizing radiation exposure.