Dermoid and epidermoid cysts are developmental pathologies that occur in the head and neck with an incidence ranging from 1.6 to 6.9%, and they represent less than 0.01% of all oral cavity cysts.
Our purpose is to report a case of sublingual epidermoid cyst of the floor of the mouth. We studied and operated on an 18-year-old white male patient showing a large swelling of oral floor. His main symptoms were difficulty breathing, swallowing, and speaking. At his birth the patient's tongue was adherent to the floor of the mouth. His father had the same problem at birth. Both father and son underwent surgical separation of tongue, during the post-neonatal period.
After the surgical removal of the swelling, under general anesthesia, all the patient's symptoms were missed. Histological examination of the mass confirmed the diagnosis of an epidermoid cyst. No relapse of the lesion was present in ten months of follow-up. Many theories are proposed on the etiology of the epidermoid and dermoid cyst. In this case a traumatic event can be found, such as an operation of the tongue in neonatal age. However a multifactorial origin must be assumed for justifying the fact that the patient's father did not develop a dermoid cyst although he had the same problem of an adherent tongue and was operated on.