External root resorptions: cone-beam computed tomography assessment and histopathological characterization.

Background: External root resorption (ERR) represents a pathological condition of uncertain etiology and variable clinical presentation that can jeopardize the long-term prognosis of affected teeth.

Aim: This study aimed to correlate radiological (cone-beam computed tomography - CBCT) and histological findings in three teeth affected by ERR with different localization (apical, middle or cervical), with a focus on the structural changes of the dental hard and soft tissues.

Materials And Methods: Two monoradicular and one pluriradicular teeth diagnosed with ERR and external cervical resorption (ECR) based on initial periapical radiography were analyzed using CBCT and lesions were measured in all three planes and described after Patel's classification; after extraction∕root amputation, samples were decalcified and processed using standard histological techniques (Hematoxylin-Eosin, van Gieson, Masson's trichrome).

Results: Several key features were noticed at the site of resorptive areas: osteoclasts, large multinucleated cells responsible for the resorption of mineralized tissues positioned along the root surface, resulting in the formation of resorption lacunae. Adjacent to the resorptive areas, granulation tissue, with a dense network of capillaries and inflammatory cells, including fibroblasts. Extensive destruction of dentin, cementum, and enamel, presence of fibrous repair, osteoid formation, and dystrophic calcifications were noticed.

Conclusions: The combined radiological-histological evaluation enhances diagnostic accuracy and may guide therapeutic strategies.