Himachal Dental


Lichen Planus – Chronic Inflammatory Disease

Lichen planus is a chronic mucocutaneous disease that affects the skin and the oral mucosa, and presents itself in the form of papules, lesions or rashes. Lichen planus doesn’t involve lichens; the name refers to the appearance of affected skin.The name of condition was provided by British physician Erasmus Wilson ,who first described it in 1869.Lichens are the primitive plants composed of symbiotic algae and fungi.The term planus is latin for flat.Even though the term lichen planus suggests a flat ,fungal condition ,current evidence indicates that this is an immunologically mediated mucocutaneous disorder.

The cause of lichen planus is not known. It is not contagious and does not involve any known pathogen. Some lichen planus-type rashes (known as lichenoid reactions) occur as allergic reactions to medications for high blood pressure, heart disease and arthritis. These lichenoid reactions are referred to as lichenoid mucositis (of the mucosa) or dermatitis (of the skin). Lichen planus has been reported as a complication of chronic hepatitis C virus infection and can be a sign of chronic graft-versus-host disease of the skin. It has been suggested that true lichen planus may respond to stress, where lesions may present on the mucosa or skin during times of stress in those with the disease. Lichen planus affects women more than men (at a ratio of 3:2), and occurs most often in middle-aged adults. Lichen planus in children is rare. In unpublished clinical observation, lichen planus appears to be associated with hypothyroidism in 3 young females.Allergic reactions to amalgam fillings may contribute to the oral lesions very similar to lichen planus, and a systematic review found that many of the lesions resolved after the fillings were replaced.

Presentation

The typical rash of lichen planus is well-described by the “4 P’s”: well-defined pruritic, planar, purple, polygonal papules. The commonly affected sites are near the wrist and the ankle. The rash tends to heal with prominent blue-black or brownish discoloration that persists for a long time. Besides the typical lesions, many morphological varieties of the rash may occur. The presence of cutaneous lesions is not constant and may wax and wane over time. Oral lesions tend to last far longer than cutaneous lichen planus lesions.

Oral lichen planus (OLP) may present in one of three forms.

* The reticular form is the most common presentation and manifests as white lacy streaks on the mucosa (known as Wickham’s striae) or as smaller papules (small raised area). The lesions tend to be bilateral and are asymptomatic. The lacy streaks may also be seen on other parts of the mouth, including the gingiva (gums), the tongue, palate and lips.
* The bullous form presents as fluid-filled vesicles which project from the surface.
* The erosive form presents with erythematous (red) areas that are ulcerated and uncomfortable. The erosion of the thin epithelium may occur in multiple areas of the mouth, or in one area, such as the gums, where they resemble desquamative gingivitis. Wickham’s striae may also be seen near these ulcerated areas. This form may undergo malignant transformation.

The microscopic appearance of lichen planus is pathognomonic for the condition

* Hyperparakeratosis with thickening of the granular cell layer
* Development of a “saw-tooth” appearance of the rete pegs
* Degeneration of the basal cell layer
* Infiltration of inflammatory cells into the subepithelial layer of connective tissue

Oral Lichen Planus Typical Featutes

* Females account for atr 65% of patients
* Patients usually over 40 years
* Untreated disease persists for 10 or more years
* Lesions in combination or isolation comprise Striae,Atropic areas and Erosion Plaques
* Common Sites are buccal mucosa,Dorsum of tongue and Gingiva
* Lesions usually occur bilaterally ansd symmetrically
* Cutaneous lesion only ocassionlly associates .
* Usually good responce to corticosteroids

Lichen planus may also affect the genital mucosa – vulvovaginal-gingival lichen planus. It can resemble other skin conditions such as atopic dermatitis and psoriasis.Rarely, lichen planus shows esophageal involvement, where it can present with erosive esophagitis and stricturing. It has also been hypothesized that it is a precursor to squamous cell carcinoma of the esophagus.

Treatment

Care of OLP is within the scope of Oral medicine speciality. Currently there is no cure for lichen planus but there are certain types of medicines used to reduce the effects of the inflammation. Lichen planus may go into a dormant state after treatment. There are also reports that lichen planus can flare up years after it is considered cured.

Some Drugs Capable Of causing Lichenoid Reactions
* Colloidal Gold
* Beta-Blockers
* Oral Hypoglycemics
* Allopurinol
* Non steroidal anti inflammatory drugs
* Anti malarials
* Methyl Dopa
* Penicillamine
* Some tricyclic anti depressants
* Thiazide diuretics
* Captopril

Features suggesting a lichenoid reactions
* Onset associated with starting drug
* Unusual severity
* Unilateral lesions or unusual distributions
* Widespread skin lesions
* Localised lesion in contact with restoration
* Lichenoid reaction are treated in same way as lichen planus with withdrawl of dtrugs if possible

Medicines used to treat lichen planus include:

* Oral and topical steroids.
* Oral retinoids
* immunosuppressant medications
* hydroxychloroquine
* tacrolimus
* dapsone
* Aloe vera

Non-drug treatments:

* UVB NarrowBand Phototherapy

Management Of Oral LP

Patients are sometimes concerned that lichen planus is infectious and should be reassured that tis is not so.Although oral lichen planus cannot be cured completely ,some drugs can provide symtomatic relief and satisfactory control.Corticosteroids are single most useful group of drugs in the management of lichen planus.The rationale of their use is their ability to modulate inflammation and the immune responce.Corticosteroids such as Beclomethasone from aerosol inhalers used for asthma can be used effectively -approx six puffs from inhaler is enough for the lesion.Triamcinole applied to the lesion is an alternative form of the treatment.Gingival lichen planus is most difficult to treat.It is essential to maintain rigourous oral hygiene .In erosive LP ,one of the stronger topical corticosteroids like Fluticasone nasal spray ,Fluocinolone,Betamathasone,Clobetasol gel applied several times per day to the most symtomatic areas is usually sufficient to induce healing within 1-2 months.The patient should be warned that he condition will undoubtedly flare up again in which case the corticosteroids should be reapplied.In addition the possibility of iatrogenic candidiasis associated with corticosteroids use should be monitored .Nystatin or Amphotericin-B suspension /Miconazole can be given in conjugation with the above.

* Always check for drugs like NSAIDS which might cause a lichenoid reaction
* Tobacco an alcohol need to be dicontinued
* Allergens need to be eliminated eg change of diet
* Infections associed with Oral Lp need to be terated eg Thrush,Hep C
* Sharp teeth and broken restorations taht cause trauma should be repaired
* Stress management ca be opted

In some cases where topical therapy fails systemic corticosteroids are effective.Antioxidants OD for Six months help improve condition.In exceptionally unresponsive cases ,tacrolimus/pimecrolimus moth rinses may be effective which must be given under strict medical supervision.Immunoregulators like levamisol have found to improve the condition of patient chronically on corticosteroids.

Advertisements

%d bloggers like this: