Short answer: most people who grind their teeth at night do not know it, because it happens while they are asleep and a lot of it is silent clenching rather than audible grinding. You find out from the evidence it leaves behind — worn or chipped teeth, jaw muscles that ache in the morning, headaches at the temples on waking, and scalloped edges along your tongue.
Why it is so easy to miss
Grinding and clenching during sleep, which dentists call nocturnal bruxism, happens with no conscious awareness at all. The muscles that close your jaw are exceptionally strong, and they can hold a load for long periods without waking you.
People often assume they would know because someone would have heard it. In practice a great deal of bruxism is static clenching, which makes almost no sound. Plenty of patients with obvious wear on their teeth have never been told they grind, and sleep alone anyway. So the sound is useful evidence when it exists, but its absence proves nothing.
The signs you can check yourself
Take these together rather than individually — one on its own means little, several at once is meaningful.
On your teeth
- Flattened back teeth. Molars have pointed cusps. If the chewing surfaces look flat, polished or shorter than they used to, that is mechanical wear.
- Small chips along the edges of your front teeth, or front teeth that appear to be getting shorter or more uneven.
- Sensitivity without decay. As enamel thins, teeth react to cold, sweetness or pressure even though nothing is wrong with them.
- Fillings or crowns that keep cracking, chipping or coming loose, particularly the same one repeatedly.
- Shiny flat spots that line up neatly with the opposing tooth when you close your jaw.
In your jaw and head
- Jaw soreness or tightness on waking, easing as the morning goes on. The timing is the clue.
- Dull headaches at the temples, worst first thing in the day.
- Tenderness just in front of your ears, or clicking and popping when you open wide.
- A jaw that feels tired partway through a meal, or difficulty opening as wide as usual.
- Aching that spreads to the sides of the head, the neck or the shoulders.
In your mouth
- Scalloped, wavy indentations along the edges of your tongue — the tongue pressing against the teeth during clenching. One of the more telling signs, and easy to check in a mirror.
- A ridged line along the inside of your cheek, level with where your teeth meet.
- Gums that have receded around specific teeth taking the most load.
- Teeth that feel slightly loose or have shifted position.
The single most useful question: is your jaw or head sore when you wake up, and does it improve over the following couple of hours? Pain that is worst on waking points to something happening during sleep, rather than to anything you did during the day.
Why it is worth confirming rather than ignoring
Enamel does not regenerate. Every bit of tooth structure lost to grinding is lost permanently, and the wear compounds: flattened teeth change how your bite meets, which changes the loads on other teeth. What starts as thinning enamel can end as cracked teeth, repeated crown failures, and eventually a need to rebuild worn-down teeth — a considerably larger and more expensive undertaking than preventing the wear in the first place.
There is also a reason not to treat grinding purely as a dental problem. Nocturnal bruxism is associated with sleep-disordered breathing, including obstructive sleep apnea, and in some patients the grinding is a downstream sign of a breathing problem during sleep. Addressing the teeth without ever asking about the sleep can mean protecting the enamel while missing the more consequential issue underneath.
What to do next
Grinding is diagnosed by examination, not from a list. We look at the wear patterns and whether they match your bite, check the jaw muscles and joint for tenderness, watch how the jaw moves, and look for the tongue and cheek signs above — then set that against what you notice about your mornings and your sleep. Part of what an exam settles is whether the wear on your teeth is old and stable or active and still progressing, which changes what, if anything, needs doing.
If you want to read about the treatment side — how jaw pain, clenching and the associated headaches are actually managed — that is covered on our TMJ and jaw pain page, and the relationship with sleep is covered at our TMJ & Sleep Center. If grinding has already damaged specific teeth, crowns are often how that gets rebuilt.
Recognise several of these?
Grinding is straightforward to confirm in an exam, and the wear it causes is much cheaper to prevent than to rebuild. We will show you what we can see on your own teeth.
Frequently Asked Questions
How can I tell if I grind my teeth if I am asleep when it happens?
You look for the evidence it leaves rather than the act itself. The most reliable signs are physical: flattened or shortened back teeth, tiny chips along the biting edges of your front teeth, jaw muscles that ache or feel tight when you wake, dull headaches at the temples first thing in the morning, and scalloped indentations along the edges of your tongue. A partner hearing the sound is helpful confirmation but relatively uncommon, because a lot of grinding is silent clenching rather than side-to-side grinding.
Why do I wake up with a headache or sore jaw?
The muscles that close your jaw are among the strongest in the body, and clenching holds them under load for long stretches while you sleep. Waking with tight or tender jaw muscles, a dull ache at the temples, or soreness in front of the ears is a classic pattern, because it reflects hours of muscle work rather than anything that happened after you woke. Headaches that are worst on waking and ease through the morning are particularly suggestive.
Can grinding damage teeth that have no cavities?
Yes, and this is the reason it is worth catching. Grinding wears through enamel mechanically, which has nothing to do with decay. It flattens the cusps of molars, chips the edges of front teeth, causes sensitivity as enamel thins, and cracks fillings, crowns and occasionally the teeth themselves. Enamel does not grow back, so wear accumulates permanently. Someone with immaculate oral hygiene and no history of cavities can still lose significant tooth structure this way.
Does stress cause teeth grinding?
Stress is strongly associated with it and many people notice their symptoms track periods of pressure at work or poor sleep. But it is not the only factor: bite alignment, certain medications, caffeine and alcohol, and sleep-disordered breathing including obstructive sleep apnea are all linked to nocturnal grinding. The connection with sleep apnea matters clinically, because treating the grinding without looking at the breathing can mean missing the more consequential problem.
What happens at an appointment if I think I grind my teeth?
We examine the wear patterns on your teeth and check whether they match your bite, look for cracked fillings and enamel thinning, palpate the jaw muscles and joint for tenderness, check how your jaw moves and whether it clicks, and look for the tongue and cheek changes that go with clenching. We will also ask about your sleep and your headaches. Between the physical evidence and the pattern of your symptoms, it is usually straightforward to confirm — and to explain which of the wear on your teeth is old and stable versus active and progressing.
This article is for general educational purposes and is not a substitute for professional dental advice or diagnosis. Grinding is diagnosed by examination, not from a checklist — if several of these signs apply to you, please book an exam rather than self-treating.
Related: TMJ & Jaw Pain Treatment · Dental Crowns · TMJ & Sleep Center · Book a Consultation