Eleven patients, all women, aged 43 to 76 years, with atrophic or ulcerative lichen planus lesions of gingiva were included in this preliminary study. After initial examination, the patients received an intensive individual hygiene treatment. The patients continued using the most appropriate, atraumatic method resulting in the best possible oral hygiene over a 1 year period during which they were seen for follow-up examinations at 3-month intervals. The mean plaque scores decreased after the initial treatment followed by an increase. The mean scores for severity of subjective symptoms and for type and extension of lesions initially decreased with the plaque scores and remained lower throughout the study. It is concluded that in some cases both subjective and objective improvement of atrophic and ulcerative gingival lichen planus may be obtained by means of intensive oral hygiene procedures although such procedures do not remove the basic cause of lichen planus. However, further studies are needed to examine the role of dental plaque control in patients with oral lichen planus.