A headache present on waking, with a tight band at the temples, is often caused by night-time clenching. How to recognise it and which simple steps help.
Many people wake with a headache and put it down to sleep or stress. Behind that description there are often chewing muscles that have been working all night. If a muscle contracts for hours, pain where it attaches is to be expected.
Why it is felt at the temple
The temporalis, one of the strongest muscles closing the jaw, spreads like a fan across the temple and attaches to the lower jaw. Contraction through the night fatigues it; the tightness felt in the morning is precisely that muscle's mark.
Patients usually describe it as a band being tightened at both sides of the head. It is pressing rather than throbbing, and is usually two-sided.
How to recognise night-time clenching
Because it happens during sleep the patient is usually unaware. The body leaves clear traces, however, and these are easily seen at examination. A grinding sound heard by a partner is a strong clue, though clenching is not always audible.
- Jaw fatigue and tight chewing muscles on waking
- Flat, shiny wear facets on the biting surfaces
- Tooth indentations along the tongue, a white line inside the cheek
- Widespread, unexplained sensitivity to hot and cold
- Fillings and crowns that break repeatedly
- Pain in front of the ear and difficulty opening on waking
Why it happens
Night clenching cannot be traced to a single cause. It is known to be linked to brief arousals during sleep, so anything that fragments sleep increases it. Stress and anxiety are the best-known triggers.
Caffeine and alcohol, smoking, certain antidepressants and sleep apnoea are other important factors. Sleep apnoea in particular should not be overlooked; where snoring and daytime sleepiness accompany it, assessment is needed.
What it does to the teeth
The force on the teeth during chewing lasts seconds; in night clenching the same force can last minutes and exceeds what is produced consciously while awake. That load shows itself at the tooth's weakest points.
The consequences include cracks in enamel, flattening of the biting surface, wedge-shaped loss at the neck of the tooth, fractured fillings and crowns, and loosening of screws in implant restorations. It is also the commonest background to cracked tooth syndrome.
What a night guard does and does not do
A night guard does not stop clenching; it distributes the force and separates the teeth. Wear then happens on the guard rather than on the teeth. Muscle tension also decreases in most patients.
A guard is therefore a protective device rather than a treatment. Hard splints made to a custom impression are more effective than soft ready-made ones; soft guards can in some patients increase the urge to chew and worsen the picture.
Headaches have other causes too
A morning headache does not always come from clenching. High blood pressure, sleep apnoea, migraine, sinusitis and certain medicines can produce the same picture. Assessment should therefore not be one-sided.
The distinguishing point is whether jaw findings accompany the pain. Where there is jaw fatigue, tooth wear and muscle tenderness, clenching is a strong possibility. If not, another cause should be sought.
Steps that help at home
The most effective habit is remembering that the teeth should not be in contact during the day; at rest the teeth are apart, the lips closed and the tongue on the palate. A small note on the screen or the mirror establishes that awareness.
- Limit caffeine and alcohol in the evening
- Apply a warm compress to the temples before bed
- Reduce hard, long-chewed foods for a while
- Stop chewing gum; it tires the muscle further
- Make your sleep schedule consistent
When to be seen
An examination is needed where a morning headache recurs several times a week, where there is visible tooth wear, where fillings break often, or where jaw pain and restriction have developed.
A picture controlled early with a splint and habit changes can, if delayed, become one requiring restoration of many teeth. Since lost enamel never returns, timing here translates directly into cost.
