– Oral lesions tend to be bilateral, mainly in the buccal mucosae.
– White lesions are common; erosions are less common. There may be lesions of
genital mucosa, skin or skin appendages.
– Reticular lesions are most often found on the buccal mucosae, sometimes on the tongue.
– Papular lesions affect similar sites. Plaque-like lesions usually affect the posterior
– Red lesions of atrophic lichen planus (LP) may simulate erythroplasia.
– Lesions may be asymptomatic or cause soreness.
– Erosions are irregular, persistent and painful, with a yellowish slough, and are often
associated with white lesions.
– LP can cause ‘desquamative gingivitis’.
– Lichen planus can have a small premalignant potential (1% ± after 10 years).
– The rash is pruritic, polygonal, purplish and papular, predominantly on flexor surfaces of wrists, and shins.
– Trauma may induce lesions (Koebner phenomenon).
– Alopecia or nail deformities are seen occasionally.
– Genital lesions are typically white or erosive.
– Common: mainly middle-aged or elderly females.
– A T-lymphocyte-mediated disorder.
– Usually no aetiological factor is identifiable.
– A minority are due to drugs, such as non-steroidal antiinflammatory drugs
(lichenoid lesions), graftversus- host disease, liver disorders, hepatitis C (possibly)
and reactions to amalgam or gold (possibly).
– Clinical: drug history; biopsy.
– Differentiate from other causes of white lesions and ulcers, especially discoid
lupus erythematosus and keratoses.
– The ‘desquamative gingivitis’ of lichen planus must be differentiated from that of mucous membrane pemphigoid.
– Asymptomatic: no treatment; reassurance and periodical (1 to 2 times/year) examinations.
– Symptomatic: corticosteroids topically and, rarely, intralesionally or systemically.
– Other drugs, such as retinoids or ciclosporin, have not proved reliably better or may have