WHITE ORAL MUCOSAL LESIONS
White lesions can be classified according to aetiology and
pathogenesis, but in many cases, it is not possible to identify
the triggering cause or underlying mechanism, and some condi-
tions are idiopathic. Some white mucosal lesions occur as a re-
action to continuous mechanical, thermal or chemical influence,
e.g. friction or smoking, while others can be manifestations of
for example genetic abnormalities, mucocutaneous diseases
or chronic inflammation. It may be necessary to take a biopsy
for final verification of the diagnosis. Whitish changes are usu-
ally an expression of keratinisation of normally non-keratinized
epithelium, increased degree of keratinisation (hyperkerati-
nisation) and/or increased epithelial thickness (hyperplasia).
Inter-/intracellular oedema in the epithelium (e.g. leukoedema)
can also appear as white lesions, and white gelatinous plaques
that can be scraped off from the mucosal surface can be a sign
of e.g. pseudomembranous candidiasis. Necrosis of the epithe-
lium gives the tissue a grey-white appearance (e.g. necrotising
gingivitis). Finally, changes in the connective tissue can mask
the blood vessels, whereby the mucous membrane appears
paler than normal (e.g. lichen sclerosus). This article reviews
some of the most common oral mucosal diseases and systemic
diseases that manifest with white oral mucosal lesions, and are
essential in relation to differential diagnosis.