They are associated to different factors: genetics, infections, hormones, addictions, solar radiation and drug interactions. They appear as lesions which are similar to lesions associated with lichen planus. In the oral mucosa they appear in annular or reticular shape, plate-shaped, or even atrophic, erosive or ulcerated areas.
Se manifiesta como lesiones similares a los diferentes tipos de liquen plano, en mucosa bucal se presenta en forma anular, reticular, en placa, o bien, zonas ulceradas, erosivas o atróficas; su localización más frecuente es en mucosa labial, yugal, alveolar, encía y cara ventral de lengua.