Image taken from Clinical Guide to Oral Diseases.
Median lip fissure is a rare benign lesion, characterized by a linear ulceration in the middle of the lower rather than the upper lip, possibly due to fusion weakness of the embryonic plates of the 1st brachial arch.
It is more common in males with male to female ratio (4/1). Patients with Down syndrome show an increased frequency of fissure tongue, median lip fissures, angular cheilitis and macroglossia among their manifestations.
The median lip fissure is a rare benign lesion that affects 6 out of 1000 patients who are usually younger than 45 years. This lesion is unrelated to chronic exposure to solar radiation, smoking or other parafunctional habits.
Plastic surgery has been used for closing deep lip fissures by using the “Z technique” with very good results and minimal recurrence.
Carbon dioxide laser has been also successfully used for fissure closure by increasing the amount of collagen and elastin subepithelially.
Pathogenic bacteria like Staphylococcus aureus or Candida species have been isolated from median lip fissures, and may respond well to the topical use of antibacterial medication alone, or in combination with antifungals.
Zinc supplements are useful for the treatment of angular and exfoliative cheilitis, but not of median fissure. The super-infection of the fissure is eliminated with the use of a combination of antifungals, antibiotics and steroids topical rather than systemic antibiotics.