[2][3] The oral mucosa in the area of crenation is usually of normal color, but there may be erythema (redness) if exposed to a high degree of friction or pressure.

[3] It is not a disease as such, but usually results from habits where the tongue is pressed against the lingual surfaces (the side facing the tongue) of the dental arches, or from any cause of macroglossia (enlarged tongue),[3] which in itself has many causes such as Down syndrome.

Where crenation is caused by parafunctional habits, there may also be associated bruxism,[4][5] linea alba,[4] or morsicatio buccarum.

In traditional Chinese medicine, scalloping of the tongue is said to indicate qi vacuity.

[6] In some homeopathic sources, scalloping of the tongue is said to be indicative of high blood pressure.