AbstractAimCemento‐osseous dysplasia (COD) is a benign, non‐neoplastic, fibro‐osseous lesion that is often asymptomatic and discovered incidentally on dental radiographs. Radiological examination, rather than biopsy, is recommended for diagnosis because of the risk of infection. The dentist working at a hospital sometimes requests a family dentist to follow up on the progress of COD discovered accidentally during panoramic radiography at a hospital. However, there are few reports on the prevalence of COD on panoramic radiographs obtained at the oral surgery department of a hospital; therefore, we investigated this in this study.Materials and methodsWe examined the prevalence of COD with calcification (classification, presence of infection, and complications with simple bone cysts) in 1194 patients for whom panoramic radiographs were obtained.ResultsTwelve patients (1.0%) had findings of COD with calcification: four cases of periapical COD (three females and one male), five cases of focal COD (four females and one male), and three cases of florid COD (three females and zero males). Infection was seen in one case of Florid COD and one case of Focal COD. A simple bone cyst was observed in one patient with Florid COD.ConclusionCOD with calcification was observed in a certain percentage of patients, and many were asymptomatic. Dental healthcare workers need to understand that COD carries a risk of infection and that there are diseases that need to be differentiated. Patients should also be advised about the need for long‐term follow‐up.