A mucocele is a type of cyst that forms in the oral cavity, most commonly on the inner surface of the lips, but it can also appear on the tongue, the floor of the mouth, or inside the cheeks. These cysts result from the accumulation of mucus due to the rupture or blockage of a salivary gland duct. Mucoceles are generally harmless and can vary in size from a few millimeters to several centimeters. They are usually painless, though larger cysts might cause discomfort.

The first documented cases of mucoceles date back to ancient civilizations where they were often mistaken for other types of oral lesions. Over time, medical understanding of mucoceles has evolved, with significant advancements in the 19th and 20th centuries. The development of better diagnostic tools and imaging technologies has helped in accurately identifying and differentiating mucoceles from other cystic lesions in the oral cavity. Surgical intervention techniques have also improved, allowing for more effective and less invasive treatments.


Mucoceles are primarily caused by trauma or injury to the salivary glands or their ducts, which can lead to the blockage or rupture of these ducts. Common causes include:

Biting or sucking on the lips or cheeks: This can damage the ducts of the salivary glands.

Oral piercings: Jewelry can irritate or injure the ducts.

Dental appliances: Braces or retainers can sometimes cause trauma to the inner mouth.

Chronic lip or cheek biting: A nervous habit that can repeatedly damage the ducts.

Risk Factors

Certain factors increase the likelihood of developing a mucocele:

  • Age: Mucoceles are more common in children and young adults.
  • Oral habits: Frequent lip or cheek biting.
  • Trauma: Any injury to the mouth, including dental procedures or sports injuries.


While mucoceles are generally not serious, potential complications can include:

Infection: If the cyst becomes infected, it may lead to increased pain and swelling.

Scarring: Recurrent or large mucoceles can sometimes cause scarring in the affected area.

Interference with oral function: Large cysts may make it difficult to chew, speak, or swallow.


Preventing mucoceles involves minimizing trauma to the mouth:

  • Avoid lip and cheek biting: Be mindful of nervous habits.
  • Use protective gear: Wear mouthguards during sports to prevent injuries.
  • Be cautious with piercings: Ensure any oral piercings are well-maintained and avoid rough handling.


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