The oral mucocele is caused by rupture, presumably due to minor trauma, of a salivary gland duct with resultant spillage of mucin into the surrounding soft tissues. It is more common in children and young adults but can affect all ages. Patients frequently report the abrupt onset of a non-tender swelling that may evolve after several weeks to a pattern of recurrent rupture followed by swelling of the lesion. There are no systemic symptoms or pertinent medical correlations.
Varix (varicosity; venous lake) – This appears blue to purple in color but affects older adults. Most varices develop over a period of months to years, and no rupture occurs.
Hemangioma – This lesion usually develops early in life with little change in size. Most will blanch with diascopy.
Benign salivary gland tumors – This presents as a constantly enlarging nodule instead of waxing and waning in size. Such tumors are often rubbery or firm on palpation.
Low-grade mucoepidermoid carcinoma – This neoplasm presents as a constantly enlarging, usually firm, mass. While it could develop in the lower lip, the posterior hard palate, soft palate, buccal mucosa and retromolar area are more common locations.
An oral mucocele is a harmless, fluid-containing (cyst-like) swelling of the lip or mouth lining (mucosa) due to mucus from the small salivary glands of the mouth leaking into the soft tissue, usually from injury (trauma) or blockage of the gland. A similar lesion, the mucus-retention cyst, occurs from blockage and backup of saliva in the gland.
Who’s At Risk
Mucoceles occur most commonly in children or young adults. There may be a history of trauma or lip biting. The similar-appearing mucus-retention cysts occur more often in older adults and without any history of preceding trauma. Tartar-control toothpaste might be the cause in some mucoceles.
Signs & Symptoms
Mucoceles usually occur on the lower lip and inner part of the cheek, as these are frequent areas of mouth trauma, but they can occur anywhere inside the mouth. A mucocele is usually a single bump with a slight bluish or normal skin color, varying in size from 1/2 to 1 inch, and it is soft and painless. A mucocele may appear suddenly, while a mucus-retention cyst may slowly enlarge.
Self-Care Guidelines
Many mucoceles will go away on their own in 3-6 weeks. Mucus-retention cysts often last longer. Avoid the habit of chewing or sucking on the lips or cheek when these lesions are present.
When to Seek Medical Care
See your doctor if the bump persists for over 2 months or if it is growing, bleeding, interfering with talking or chewing, or painful.
Treatments
If the doctor is not sure of the diagnosis, a biopsy may be done. Minor surgery may be suggested to remove the lesion.
References
Bolognia, Jean L., ed. Dermatology, pp.1729-1730. New York: Mosby, 2003.
Patient Information for Oral mucocele - Oral Mucosal Lesion