Abstract
White lesions usually contain an increased amount of keratin. Some are rare congenital conditions, such as white sponge naevus and dyskeratosis congenita, unlikely to be seen in general dental practice. Inflammatory causes include candidosis and hairy leukoplakia, both now common in HIV disease. Non-infective causes include the common lesion of lichen planus, and the less common condition lupus erythematosus. Neoplastic and possibly preneoplastic causes include carcinoma, keratoses and leukoplakia. This article discusses the more common causes of oral white lesions. The first article in this series presented several general observations on diagnosis and treatment which should be borne in mind in relation to this article.