What does this mean?
Grinding happens when the chewing muscles tighten rhythmically while you are asleep. Your lower jaw slides from side to side as they do, and the side surfaces of your teeth rub against each other; that is where the sound comes from. Because you are asleep you do not feel any of it, which is why someone else is most often the one who tells you about it.
The sound is the detail that separates clenching from grinding. In clenching the jaw stays where it is and the force is applied straight down; there is no rubbing, so there is no sound. That is why nobody hearing anything does not mean there is no clenching. A second detail: loudness is not a measure of the damage. How much harm has been done is judged not by ear but by the flattening on the biting surfaces, the chipped edges of fillings and crowns, and increasing sensitivity.
Wear is the part of this picture that cannot be undone. Enamel is not rebuilt; the thickness that has gone is not expected to come back, so the point of an assessment is to protect what is left. Grinding can also become more frequent after the moments when breathing is disturbed in sleep, so when the sound is asked about, snoring, breathing pauses someone has witnessed and a dry mouth in the morning are asked about alongside it.
Night grinding does not have a single cause; the muscle working through the night, breathing during sleep and acid coming up from the stomach can all add to the same picture. The headings below are not a ranking, they are the possibilities looked at together at an examination.
Likely causes
What helps at home?
- Record the sound on your phone for a night or two; that shows more clearly whether grinding is really happening and how often it comes back during the night. Bring the recording to your appointment.
- Do not use ready-made guards from a chemist or the internet, the sort you shape in hot water, on your own judgement; a guard not made from an impression can move teeth out of place and change your bite.
- Do not rush into having worn teeth crowned because of how they look; new surfaces made while the grinding carries on can be damaged the same way.
- Do not chew gum to work the muscles and get your jaw ready for the day; a muscle that has already been tightening all night can hurt more when daytime load is added to it.
- If the person who hears the sound says your breathing stops during the grinding, or that you seem to be choking
- If you cannot open your mouth in the morning, your jaw locks, or the opening has dropped below two fingers' width
- If a tooth has clearly broken or started to loosen over a short period
- If movements you cannot stop have also started in your jaw or your tongue during the day, without you noticing them
- If the sound started after you began a new medicine; do not stop it yourself, speak to the doctor who prescribed it
Frequently asked questions
- Will a night guard stop the grinding?
- A night guard is there to protect the teeth; it is not expected to remove the grinding itself. The muscles can carry on tightening at night, but the force is spread over the guard, and the wear progressing and the risk of a tooth breaking can both be reduced. The type of guard, its thickness and which jaw it is made for are decided at an examination. If there are findings that suggest a breathing problem in sleep, an assessment of that side of things may be asked for before the guard is decided on.
- Will my worn teeth repair themselves?
- They will not. Enamel is not a tissue that renews itself the way bone does; the thickness that has gone is not expected to come back. So what is measured is not whether the teeth return to how they were, but whether the loss has stopped. Wear can be followed by comparing photographs or records taken inside the mouth at set intervals; if it is still progressing, the cause needs looking at again.
- Is this entirely down to stress?
- Stress is one of the factors mentioned most often, but it is not seen as the only thing that decides it. Breathing being disturbed in sleep, acid coming up from the stomach into the gullet, alcohol and smoking, and some medicines are all mentioned alongside this picture too. An approach aimed at stress alone can miss an underlying cause in sleep or in the stomach, which is why the questioning is not left at a single heading.
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.