What does this mean?
When the covering layer on the surface of the lining thickens in narrow strips, it reflects light differently and those strips look white. Where they overlap, it is as though a fine lace or fern pattern has been drawn on the inside of the cheek. The pattern usually sits on both cheeks at once, below the level where the teeth meet, and is more or less symmetrical. In many people it causes no symptoms at all and is noticed during a routine examination.
Three details separate this appearance from the ones it resembles. The first is that it does not wipe away: the white coating of oral thrush lifts off with gauze and leaves a red base underneath that bleeds easily, whereas these lines stay. The second is that it is a pattern: healthy lining shows between the lines, whereas a thick white patch is a single, smoothly bordered area, most often on one side only. The third is symmetry; being present on both cheeks supports this appearance. A single straight white line running along the biting level of the cheek is something else, a pressure mark, and it does not form a network.
When the appearance stays as lines alone, it most often causes no symptoms. When the same process thins the lining and creates red, eroded areas, burning begins with sour, spicy and hot foods; if the gums are involved they may turn red and peel, and bleed easily when brushed. This is not something a single course of treatment closes off; it calls for check-ups at intervals. Some medicines, and contact with certain materials in the mouth, can produce a very similar appearance, so the list of medicines you take is part of the assessment.
Lacy white lines are not specific to a single condition; several different conditions, each taking its own course, can produce a similar appearance. The headings below gather the places where that distinction is made.
Likely causes
What helps at home?
- If the lines are not burning, do not try to scrape them off or scrub them with a brush; this is not a layer of dirt, and friction irritates the lining.
- If there is burning, leave off acidic and heavily spiced foods, alcohol-based mouthwashes and strongly minted toothpastes for a while and see whether it makes a difference.
- Bring a list of the medicines you take; some medicines can produce a very similar reaction in the lining of the mouth, and that only comes to light by asking.
- Stop smoking and using tobacco products; they can make the symptoms worse and make changes in the area harder to follow.
- Red areas that will not heal, or areas that have turned into open sores, have formed between the white lines.
- The appearance is on one cheek only, as a single thick white plaque.
- The burning stops you eating enough, or you are losing weight.
- Your gums are turning red and peeling, and bleed even with gentle brushing.
- You have noticed a hardened lump, or a swelling that will not go away, in the same area.
Frequently asked questions
- Are these white lines oral thrush?
- Most likely not. The white layer of oral thrush wipes off with gauze and leaves a red base underneath; these lines do not wipe away. A simple wiping test at the examination usually shows the difference. If doubt remains, a small sample can be taken and examined.
- Will it go away, does it need treatment?
- When the appearance causes no symptoms and consists of lines alone, it most often needs no drug treatment; check-ups at set intervals may be enough. If there is burning, redness and erosion, treatment with medication is planned. This picture is not always expected to disappear altogether; the aim is usually to settle the symptoms and to keep the area under review.
- Is there a risk of it turning into cancer?
- Cellular change over time has been reported in a small proportion of the people followed with this condition; the rate is low, but that is precisely why keeping up the follow-up is advised. What makes a change visible early is looking at the same area at regular intervals and taking a sample from any area that raises doubt.
This content is for general information and does not replace an in-person examination. Symptoms overlap between conditions, and a diagnosis can only be made clinically.