Oral Lichen Planus

Introduction-Oral lichen planus (OLP) is a chronic inflammatory disease that causes bilateral white striations, papules, or plaques on the buccal mucosa, tongue, and gingivae. Erythema, erosions, and blisters may or may not be present.

PATHOPHYSILOGY-Current data suggest that oral lichen planus is a T-cell–mediated autoimmune disease in which autocytotoxic CD8⁺ T cells trigger apoptosis of oral epithelial cells.

ONSET- In many patients, the onset of oral lichen planus is insidious, and patients are unaware of their oral condition. In such instances, the referring medical or dental practitioner identifies the clinical changes in the oral mucosa.

Some patients report a roughness of the lining of the mouth, sensitivity of the oral mucosa to hot or spicy foods or oral hygiene products, painful oral mucosa, sore gums, red or white patches on the oral mucosa, red gums, or oral ulcerations.

Approximately two thirds of patients with oral lichen planus report oral discomfort, especially in association with atrophic and erosive lesions. Erythematous and erosive lesions are often sensitive or painful. Symptoms vary from mucosal sensitivity to continuous debilitating pain.

Oral mucosal lichenoid lesions may occur after the administration of systemic drugs such as nonsteroidal anti-inflammatory drugs (NSAIDs), sulfonylureas, antimalarials, beta-blockers, and some angiotensin-converting enzyme (ACE) inhibitors. The period between the commencement of the drug therapy and the clinical appearance of oral lichen planus–like disease varies.

In rare cases, oral mucosal lichenoid lesions occur after a dental restoration is performed or after the patient starts using a denture; the lag period varies. Patients with an associated allergy to metals or components of the appliance should be evaluated by means of patch testing.

Patients with reticular lesions are often asymptomatic, whereas those with atrophic (erythematous) or erosive (ulcerative) disease commonly have significant local morbidity. The oral pain is variable and exacerbated by trauma and foods, particularly those that are hot, spicy, or acidic.

Oral mucosal lesions are variable and present as white striations (Wickham striae), white papules, white plaques, erythema (mucosal atrophy), erosions (shallow ulcers), or blisters. The lesions predominantly affect the buccal mucosa, tongue, and gingivae, although other oral sites are occasionally involved. The lesions are usually bilateral.

The lesions may appear as a mixture of clinical subtypes. For example, white streaks and gray streaks may form a linear or reticular pattern on an erythematous background. Alternatively, a central area of shallow ulceration (erosion) may have a yellowish surface (fibrinous exudate) surrounded by an area of erythema.

In most patients, telltale white striations or papules are evident on the buccal mucosa or on the lateral margin of the tongue, either alone or in combination with other lesions.

Gingival lesions commonly appear with a fiery red erythema that affects the entire width of the attached gingiva, a condition previously called desquamative gingivitis.

In patients predisposed to pigmentation, oral lichen planus lesions may be associated with patchy brown melanin deposits in the oral mucosa (inflammatory melanosis).

Oral lichen planus lesions usually persist for many years with periods of exacerbation and quiescence. During periods of exacerbation, the area of erythema or erosion increases, with increased pain and sensitivity. During periods of quiescence, the area of erythema or erosion decreases, with decreased pain and sensitivity. Patients are often unaware of quiescent oral lichen planus, which may manifest as faint white striations, papules, or plaques. Exacerbations of oral lichen planus have been linked to periods of psychological stress and anxiety.

Lichenoid drug reactions have the same clinical features as those of idiopathic oral lichen planus. Lichenoid disease may be unilateral and associated with circulating epithelial antinuclear antibodies, but few data support this possibility. Rarely, lichenoid reactions of the oral mucosa occur on the oral mucosa in contact with (or close to) an amalgam or composite resin dental restoration, or a denture component. Mechanical trauma (the Koebner phenomenon) may exacerbate lichenoid lesions, especially when it affects the midline of the buccal mucosa or the lateral margin of the tongue.

In many patients, a cause for the oral lichenoid lesions cannot be identified; in these patients, the disease is called idiopathic oral lichen planus.

Oral lichenoid drug reactions may be triggered by systemic drugs including NSAIDs, beta-blockers, sulfonylureas, some ACE inhibitors, and some antimalarials. In patients with oral lichenoid lesions, be alert for any systemic drug as a cause.

Oral lichenoid contact-sensitivity reactions may be triggered by contact allergens including dental amalgam composite resin, and toothpaste flavorings, especially cinnamates.

Oral lichenoid lesions may be triggered by mechanical trauma (Koebner phenomenon) due to calculus deposits, sharp teeth, rough surfaces of dental restorations or prostheses, cheek or tongue biting, and oral surgical procedures. Scale any teeth associated with oral lichen planus lesions to remove calculus deposits and reduce sharp edges. Dental restorations and prostheses that are associated with oral lichen planus lesions should be mirror-polished.

DIFFERENTIAL DIAGNOSIS- Leukoplakia; Candidiasis ;Phemphigoid

TREATMENT-Medical treatment of oral lichen planus (OLP) is essential for the management of painful, erythematous, erosive, or bullous lesions. The principal aims of current oral lichen planus therapy are the resolution of painful symptoms, the resolution of oral mucosal lesions, the reduction of the risk of oral cancer, and the maintenance of good oral hygiene. In patients with recurrent painful disease, another goal is the prolongation of their symptom-free intervals.

The main concerns with the current therapies are the local and systemic adverse effects and lesion recurrence after treatment is withdrawn. No treatment of oral lichen planus is curative.

Advise patients with oral lichen planus to do the following:

• Eliminate smoking and alcohol consumption.
• Eat a nutritious diet, including fresh fruit and vegetables, because this may help reduce the risk of oral cancer.
• Pay attention when symptoms are exacerbated or when lesions change.
• Be aware of the need for regular re-examination and repeat lesion biopsy, especially if clinical changes in the lesion occur.
  Topical corticosteroids are the mainstay of medical treatment of oral lichen planus, although rarely, corticosteroids may be administered intralesionally or systemically. Some topical corticosteroid therapies may predispose the patient to oral pseudomembranous candidosis. However, this condition is rarely if ever symptomatic, and it generally does not complicate healing of the erosions related to oral lichen planus. Topical antimycotics (eg, nystatin, amphotericin) may be prescribed when an infection is present

Eliminate local exacerbating factors. Treat any sharp teeth or broken restorations or prostheses that are likely to cause physical trauma to areas of erythema or erosion by using conventional dental means. Scale the teeth to remove calculous deposits and reduce sharp edges. If the patient has an isolated plaquelike or erosive oral lichen planus lesion on the buccal or labial mucosa adjacent to a dental restoration, and if an allergy is detected by means of skin patch testing, the lesion may heal if the offending material is removed or replaced. (However, most lichenoid lesions adjacent to dental restorations are asymptomatic.)

If systemic drug therapy (eg, treatment with NSAIDs, antimalarials, or beta-blockers) is suspected as the cause of oral lichenoid lesions, changing to another drug may be worthwhile. This change must be undertaken only by the patient's attending physician. However, the switch rarely resolves the erosions, and almost never resolves the white patches of oral lichen planus.

Inform all patients with oral lichen planus about their slightly increased risk of oral SCC (the most common of all oral malignancies). As with all patients, advise those with oral lichen planus that this risk may be reduced by eliminating tobacco and alcohol consumption and by consuming a diet rich in fresh fruits and vegetables, among other measures (see Complications). Erosive and atrophic lesions can be converted into reticular lesions by using topical steroids. Therefore, the elimination of mucosal erythema and ulceration, with a residual asymptomatic reticular or papular lesions, may be considered an end point of current oral lichen planus therapy. With respect to plaque lesions, the effect of treatment on the risk of oral cancer is unclear.

Immunosupressants like cyclosporine,azathioprine should also be prescribed.