Dermoid and Epidermoid Cysts of the Oral Cavity: Experience with 8 Cases

Epidermoid (EC) and dermoid (DC) cysts of the oral cavity are rare, benign congenital developmental malformations that develop from abnormally situated ectodermal tissues. EC and DC are more common in the rest of the body. Their exact development is yet to be described. The distinction between EC and DC can only be made by histopathologic examination. The EC is lined by keratinized stratified squamous epithelium and composed of an ectodermic layer. In contrast, DC is lined by stratified epithelium (dermis) with skin adnexa (sebaceous glands, sweat glands, and hair follicles). DC and EC are rare in the head and neck region with only 1.6% occurring in the oral cavity and about 7% of all the ECs and DCs of the body. The majority of ECs and DCs occur in the sublingual region presenting as slow-growing midline asymptomatic swellings that may enlarge leading to progressive dysphagia, dyspnea, and compromised speech. There is no gender predilection, although some reports indicate male preponderance. Surgery is the treatment of choice. We present our experience with 8 cases of large EC and DC.