Calcification of the stylohyoid ligament in panoramic radiography and cone beam computed tomography among patients referred for dental implant treatment planning

Calcification of the stylohyoid ligament (SHL) is a common condition noted as an incidental finding in routine radiographic examination. Due to proximity with important neurovascular structures, elongation and calcification may sometimes lead to dysphagia and pain. The objective of this study was to evaluate the incidence of calcified SHL detected on cone beam computed tomography (CBCT) scans and panoramic radiographs (PR) in patients referred for dental implant therapy. Retrospective analysis of 30 patients referred for dental implants to the Department of Oral and Maxillofacial Radiology at the University of Connecticut School of Dental Medicine was done. Patients were imaged using Hitachi CB MercuRay CBCT machine, and PRs were obtained using Planmeca panoramic machine. CBCT reconstructions and panoramic images were evaluated for the incidence and pattern of SHL calcification. Nineteen patients (63.3%) had calcified SHLs, 16 of whom were reported to have bilateral involvement. PR was unable to show complete calcification of the ligament in any of the cases, whereas CBCT showed evidence of complete calcification when present (14 cases). CBCT was more accurate in determining the pattern and extent of calcification of the SHL in patients undergoing implant treatment planning.