Mucous cysts develop when salivary glands become plugged. They’re usually temporary, but if left untreated, they can become permanent. A mucous cyst, also known as a mucocele, is a fluid-filled ...

Oral mucous cysts develop in the mouth. They appear near salivary gland openings, often on the lips or the floor of the mouth. A cyst on the floor of the mouth is known as a ranula. A cyst on the gums ...