These striated (reticulated or lace-like) white lines look like a lichenoid reaction or oral lichen planus.
Both conditions are auto-immune meaning that your immune system attacks the cells that form the lining of the mouth (the mucosa) causing inflammation and these white striations.
Lichenoid reactions may be caused by certain medications, oral care products or even a sensitivity to metallic restorative materials (such as amalgam or other metals). Replacement of the metals with non-metallic materials (composite or ceramic) can resolve the lesion.
Lichenoid reactions triggered by medication is usually one-sided and coincides with commencing treatment with a new drug. The mucosa returns to normal once the offending drug is stopped, which is not the case with lichen planus.
Severe cases of erosive/ulcerative lichen planus show background ulceration of the mucosa which can be extremely painful. When there is ulceration, these areas may become infected by yeast (candidiasis). Severe cases are treated with topical corticosteroids (usually in a mouthrinse or a paste) to reduce the auto-immune inflammation. Other newer methods of treatment include topical immunosuppressants, topical anti-inflammatories, retinoids and lasers. However, these are reserved for very resistant forms of the disease that do not respond well to topical corticosteroids.
A biopsy (where a small sample of tissue is removed and sent for microscopic examination) of the affected area is the most reliable way to differentiate lichenoid reactions from oral lichen planus and other mucosal diseases that look very similar.
There is no cure for lichen planus at present and treatment is aimed at reducing the severity of the disease (going from ulcerative to the non-ulcerative reticulated form of the disease). Long term follow up is essential.
