What does this mean?
The tongue is a muscular organ that settles into the space inside the mouth. When that space is tight for the tongue, or when the tongue presses constantly against the teeth, the shape of the row of teeth is printed on its edge. What you see is a run of soft indentations along both sides of the tongue, lined up with the position of the teeth. The marks being on the edge rather than on the top is what separates them from the changes in colour and texture seen on the surface of the tongue.
The marks being clear in the morning and fading as the day goes on is a commonly reported feature; contact and pressure carry on through the night and are at their highest first thing. The indentations are not lasting damage to the tissue, and the edge is expected to settle once the pressure is gone. Alongside this, people may report that the marked edges become tender, that the tongue feels tired and that it catches on the teeth while they speak.
This finding is not an illness in itself but the mark left by a habit or by a structural narrowness. Clenching the teeth at night and during the day, the habit of pushing the tongue against the teeth when swallowing, a narrow upper jaw, mouth breathing because of a blocked nose and swelling of the tongue are the backgrounds met most often. In some people redness and burning along the edge go with it; in that case not only the pressure but the irritation of the surface is assessed as well.
Marks along the edge of the tongue raise the question of why the tongue is pressing against the teeth. The headings below bring together the causes met most often behind this appearance.
Likely causes
What helps at home?
- Check a few times during the day where your tongue is resting; the expected position is with the tip against the palate, not against the teeth.
- Your teeth do not need to touch each other all day long; aim to keep a small gap between the upper and lower teeth while your lips stay closed.
- If the edges are irritated, keep away from hard brushing and from very spicy and acidic food for a while.
- Do not use ready-made night guards bought online without impressions being taken; an appliance that has not been fitted to your mouth can shift the position of your teeth.
- If there is an ulcer that will not heal, or a hardened area, on the marked edge.
- If the redness and burning along the edge carry on regardless of eating.
- If in the mornings you get pain in the jaw joint, locking, or difficulty opening your mouth.
- If there is one-sided enlargement of the tongue, numbness or a change in taste.
- If the marks have appeared over a short time together with obvious swelling of the whole tongue.
Frequently asked questions
- Do tooth marks mean my tongue has grown bigger?
- Most of the time, no. The same picture can arise when the tongue is a normal size and the dental arch is narrow, or from a habit of pressing the tongue against the teeth. Cases where the tongue really has enlarged are less common and usually come with other findings.
- Is it connected with clenching my teeth?
- It is one of the things associated with it. During clenching the jaw muscles tighten and the tongue presses against the teeth and the edges; that is why marks that are more obvious in the morning are often reported alongside clenching. Even so, the marks on their own do not diagnose clenching; that is assessed by examination.
- Do the marks go away on their own?
- The edge is expected to settle once the pressure is gone; as long as the habit or the narrowness carries on, it is usual for the marks to reappear. That is why the real issue is not the marks themselves but why the tongue is pressing.
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.