OMFS-0120Soft-tissue lesionsPathologybeginnerLower lip

Recurrent bluish swelling of the lower lip in a teenager

15-year-old female

Draft — educational study aid, pending faculty review.

§Chief complaint

Painless bubble on the lower lip that bursts and comes back

§Medical & dental history

01Fit and well
02Habit of biting the lower lip

§Clinical examination

01Dome-shaped, bluish, fluctuant swelling 9 mm on the left lower labial mucosa
02Non-tender, no bleeding, mucosa intact
03History of rupture with clear viscous fluid discharge and recurrence
04No other lesion in the mouth

§ figuresFigures (3)

Mucocele — clinical image: Surgical removal of a mucocele in the lower lip. — Fig. 1Surgical removal of a mucocele in the lower lip.
“Surgical removal of a Mucocele.” · Jeffrey Dorfman · CC BY-SA 3.0 · Wikimedia Commons

Verified open-access images only, reproduced for education under their stated licences · no AI-generated or illustrative artwork · Mucocele figures pending faculty review.

§Differential diagnosis

Mucocele (extravasation type)Young patient, lower lip, trauma, bluish fluctuant swelling

Salivary duct cystOlder patient, true epithelial lining, floor of mouth or buccal

HaemangiomaBlanches on pressure, present since childhood

Minor salivary gland tumourFirm, on palate rather than lip

§Final diagnosis

Mucous extravasation phenomenon (mucocele) of the lower lip

Location on the lower lip, a young patient, a history of lip-biting trauma, and recurrent rupture-and-refill are the discriminators. A haemangioma blanches; a salivary gland tumour is firm and typically palatal.

§Investigations

01Clinical diagnosis; transillumination shows a fluid-filled lesion
02Excisional biopsy confirms and treats

§Treatment plan

01Excision of the mucocele together with the feeding minor salivary glands
02Address the lip-biting habit to prevent recurrence

§Surgical procedure

01Elliptical incision, lesion dissected with the adjacent minor salivary glands
02Careful protection of the mental nerve branches
03Primary closure with 5-0 resorbable sutures

§Histopathology report

Mucin pool surrounded by granulation tissue and foamy macrophages without an epithelial lining, with adjacent inflamed minor salivary gland tissue. Mucous extravasation phenomenon.

§Follow-up & outcome

01Healed uneventfully
02No recurrence at 12 months once habit stopped

§Clinical pearls / learning points

01Removing the mucin without the feeding gland guarantees recurrence.
02Extravasation mucoceles have no epithelial lining; retention cysts do.
03A 'mucocele' on the hard palate or in an older adult should be biopsied as a possible neoplasm.

§ evidenceReferences & Evidence

Current Classification

WHO Classification of Tumours Online — Head and Neck

IARC / WHO · 2022

Continuously updated online edition of the WHO head and neck tumour classification.

View official source

Evidence summary

Highest level of evidence linked to this page: WHO / Official Classification.

L1 · Classification — 1
L6 · Textbook — 3

1 linked source was published from 2024 onwards. Where guidance is limited or contested, rely on the higher-level sources above rather than this summary. Educational use only — not a substitute for clinical judgement.

Content last reviewed

September 2026

Evidence last reviewed

September 2026

Next scheduled review

September 2027

Review status

EVIDENCE REVIEWED

Search latest PubMed evidence

Last literature search: 7 September 2026

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Current Classification