Surgical ciliated cyst a newly added entity in WHO classification of head and neck tumours (2022): A case report.

The surgical ciliated cyst is a newly added entity under the cysts of the jaws in the World Health Organization (WHO) Classification of Head and Neck Tumours (2022). It is preceded by a prior surgery to the jaw many years before its diagnosis. A 53-year-old Chinese female, who had undergone cleft lip and palate repair followed by orthognathic surgery before the age of 20, was referred for management of an incidentally found cyst in the left maxilla. A cone-beam computed tomography revealed a unilocular, well-defined radiolucent lesion periapical to tooth 26. A provisional diagnosis of radicular cyst was given, and the cyst was enucleated under general anaesthesia. Histopathological examination showed a multicystic lesion lined by pseudostratified ciliated columnar epithelium. This case was diagnosed as a surgical ciliated cyst based on the history of previous surgery to the maxillary region, radiographic and histopathological features, which are the three essential features for diagnosis based on the WHO Classification (2022). Surgical ciliated cysts are a rare complication of orthognathic surgery which may be underreported in populations outside Japan. Now that it has been added to the latest WHO Classification, the diagnosis of this entity may be more common than previously reported.