Teeth clenching and grinding (bruxism): symptoms and the night guard

Bruxism is unconscious clenching or grinding of the teeth. It mostly happens during sleep, and people learn of it either from a partner or when the dentist notices wear facets. Stress, sleep disorders, bite problems and some medicines are triggers.

Symptoms

• Pain or fatigue in the jaw, temples or in front of the ear in the morning
• Frequent headaches, especially on waking
• Teeth looking flattened and shortened; notches on the incisal edges
• Cold sensitivity, notch-shaped wear at the gum line
• Fillings and crowns breaking often
• Clicking in the jaw joint, limited mouth opening
• Tooth imprints on the inside of the cheek, scalloping along the tongue edge

Why does it matter?

Clenching forces can reach several times the chewing force. Enamel wears, teeth fracture, crowns are damaged, gums recede and the jaw joint is strained. In the long run the teeth shorten and the face changes.

The night guard

A hard or semi-hard acrylic splint made to an impression is worn at night. It separates the teeth, preventing wear, and relaxes the jaw muscles; it does not stop clenching altogether but removes its harm. Over-the-counter guards are soft and thick; with long-term use they can disturb the bite and are not recommended.

Other approaches

• Stress management, sleep routine, less caffeine and alcohol in the evening
• Daytime awareness: "teeth apart, lips together"
• Orthodontic or prosthetic correction if there is a bite problem
• Muscle-relaxation measures and physiotherapy; medical assessment in resistant cases

Repairing worn teeth

Once bruxism is under control, shortened teeth can be restored to their original height with composite or porcelain restorations; restorations made without a night guard are damaged quickly.

Sleep bruxism or daytime clenching?

They are managed differently. Sleep bruxism is linked with arousal responses (micro-awakenings); it may accompany snoring and sleep apnoea, in which case a sleep specialist's assessment is needed. Daytime clenching happens during tasks needing concentration, screen work and stress; usually silent, just clenching. For daytime clenching, awareness exercises (teeth apart, tongue on the palate) and reminders work better than a guard.

Bruxism in children

Up to a third of children grind in their sleep; it is often related to the changeover of primary teeth and subsides on its own in adolescence. Without excessive wear, pain or a sleep disorder (snoring, adenoids) it is only monitored; a guard is made in selected cases.

Bruxism and headache

A dull morning headache at the temples, pain in front of the ear and tender jaw muscles — sometimes mistaken for migraine. It stems from continuous night-time contraction of the jaw muscles (masseter, temporalis); a night guard and muscle-relaxation exercises reduce it. In severe cases the dentist considers additional measures aimed at the jaw muscles.

How are worn teeth repaired?

• Mild incisal-edge wear: shape is rebuilt with composite bonding
• Notches at the neck (abfraction): composite fillings
• Marked loss of tooth substance and shortened teeth: vertical dimension is restored with onlays/crowns; a trial with a splint first
• Cracked teeth: a crown or root canal treatment depending on the depth of the crack

A night guard is essential after repair; otherwise the new restorations will wear and break too.

What you can do day to day

• Cut evening caffeine and alcohol; switch off screens an hour before bed
• An hourly "are my teeth touching?" check during the day; if so, tongue on the palate, teeth apart
• No chewing gum, no biting pens or nails
• 10 minutes of warmth on the jaw muscles before bed
• Stress management; psychological support if needed

When is further investigation needed?

If pauses in breathing during sleep, excessive daytime sleepiness and loud snoring accompany bruxism, sleep apnoea is investigated; treating the apnoea also reduces the bruxism. More: Who needs a night guard? · Jaw joint pain