A Large Dermoid Cyst in the Floor of the Mouth.

The dermoid cyst in the floor of mouth is considered to bea rare condition which comprises only 1.6 to 6.5% of all body dermoid cysts. Dermoid cyst in the floor of mouth may be congenital or acquired. The congenital form results from defective embryonic development and the acquired form may be due to traumatic or iatrogenic causes; and as a result of the occlusion of a sebaceous gland duct. We report an unusual case of huge dermoid cyst in the floor of the mouth in a 12 year old male who presented with progressively increasing swelling below his tongue and reviewed the relevant literature.