Bruxism refers to repetitive jaw-muscle activity characterised by clenching, grinding, or bracing of the mandible. It may occur during sleep (rhythmic “grinding” or tonic “clenching”) or wakefulness (jaw bracing or tooth contact without noise).

Tooth contact, jaw clenching or grinding may be completely benign; or it may indicate a pain source, create dental risk, or reflect an underlying sleep or neurological condition.

Estimates vary due to differing definitions and diagnostic criteria, but bruxism is common across all age groups: about 8% of adults, 14–46% of children and adolescents, and around 3% of older adults. Recent large-scale epidemiological studies suggest a population prevalence of roughly 25%.

For GPs, the key issue is not whether bruxism occurs, since most people clench or grind their teeth occasionally, but whether it is clinically significant.

Clinical significance: behaviour versus pathology

When a patient presents with concerns about teeth grinding or clenching, it is crucial to recognise bruxism as a sign, rather than a diagnosis in itself.
Not everyone who grinds their teeth requires treatment. If a patient’s partner reports nocturnal grinding, but they wake refreshed without pain, and have no evidence of dental wear, muscle tenderness, or joint dysfunction, they require reassurance, not treatment.
Bruxism becomes clinically significant when it is associated with pain, TMJ dysfunction, or damage to the teeth.
Patients may report pain or tightness in the masseter, pre-auricular area (TMJ), or temporalis regions, often most noticeable on waking, together with morning jaw stiffness, fatigue, or temporal headaches.
Functional impairment may also be evident.

This could include:

• difficulty opening the mouth fully
• pain or fatigue when chewing
• episodes of jaw locking or catching

In some cases, dental changes provide additional clues. These include chipped or worn incisal edges, flattened occlusal surfaces, and/or damage to dental restorations. When these features are present, bruxism is no longer a benign behavioural habit but a clinically significant process requiring assessment with a dentist and, where appropriate, intervention.
In some contexts, bruxism may even be protective. For example, during gastro-oesophageal reflux, nocturnal clenching may stimulate saliva flow to neutralise acid; in obstructive sleep apnoea, jaw protrusion may transiently maintain airway patency. In such cases, bruxism is a sign of another condition, and management should focus on the underlying disorder.

Risk context and associated conditions

Multiple factors can trigger or exacerbate bruxism and TMD. Substances such as alcohol (especially before sleep), caffeine, tobacco, amphetamines, cocaine, and SSRIs can increase risk. Sleep disorders including snoring, obstructive sleep apnoea, parasomnias, restless legs, and chronic insomnia are common associations.
Neurological conditions such as ADHD, epilepsy, Parkinson’s, and traumatic brain injury are also linked.
Stress is a recognised risk factor but is often over-attributed. While psychosocial stress contributes to muscle tension and bruxism, GPs should also consider concurrent medical, neurological, or sleep-related causes. Identifying and addressing these factors can help manage symptoms and reduce the risk of dysfunction.

Focused assessment in primary care

Ask about jaw, temple, or pre-auricular pain or stiffness, particularly on waking, and temporal headaches, or jaw fatigue. Inquire about locking, catching, or clicking of the TMJs, reduced mouth opening, teeth wear or chipping, and any damage to restorations. Screen for sleep related breathing disorders (snoring, witnessed apnoeas, unrefreshing sleep), reflux, medication and substance use, and psychosocial stressors.
On examination, palpate the masseter, temporalis, and TMJ for tenderness or pain. Assess mouth opening, as typical adults open about 50 mm; less than 25 mm (around two fingers) suggests dysfunction. Observe for deviation on opening or TMJ clicking or crepitation, and inspect teeth for wear, acknowledging that wear may reflect past rather than current activity.

Three-question TMD screen

1. Is there jaw pain (masseter, TMJ, or temporalis region)?
2. Is there dysfunction or pain when chewing?
3. Is there locking or catching of the jaw?

Practice tip: A positive response to two or more TMD screening questions warrants dental or oral medicine specialist referral rather than immediate imaging.

Investigations

The diagnosis of sleep bruxism is based on history and examination. A level one sleep study with audiovisual recording is the established gold standard, but it is rarely required outside research settings or when sleep disorders such as obstructive sleep apnoea are suspected. Ambulatory devices for multi-night monitoring are emerging but are not yet mainstream. Imaging with MRI or CT of the TMJs is not routinely required and should be considered only in selected cases, such as in a persistent closed-locked jaw due to disc displacement without reduction, or when structural changes within the joint are suspected. Routine imaging seldom changes management and can lead to overdiagnosis.

Management principles

Most patients benefit from education and reassurance that TMDs are self-limiting conditions and respond well to conservative management. TMDs rarely progress to a chronic disabling condition. Advise a soft diet during painful flares, avoiding hard or chewy foods. Encourage awareness of daytime habits such as nail biting, gum chewing, chin resting, and sustained tooth contact. Simple relaxation cues, such as using a visual prompt to drop the shoulders, can reduce jaw tension. If applicable, stress management strategies should be considered.

Practice tip: Encourage patients to use a visual cue, such as a sticker on their monitor or dashboard, to remind them to drop their shoulders and relax the jaw during the day.

Gentle stretching exercises can be performed by resting the tongue on the palate and slowly opening the mouth to a comfortable maximum, holding for six seconds and repeating several times a day. If nocturnal bruxism or tooth wear is evident, a custom occlusal splint can protect the teeth and reduce muscle and joint loading. Short courses of NSAIDs (diclofenac, naproxen, or celecoxib if tolerated) or paracetamol may help during acute episodes. Benzodiazepines are not recommended.

Longer term management

A small subset of TMD patients develops chronic pain due to central sensitisation (nociplastic pain). Predictors include widespread pain syndromes such as low-back or pelvic pain, migraine, irritable bowel syndrome, chronic fatigue, insomnia, adverse childhood experiences, anxiety, and depression. Management requires a biopsychosocial approach, addressing sleep, activity, nutrition, psychosocial context, and stress.
Referral for psychological or pain-specialist input is appropriate where distress, poor coping, or insomnia persist. Membrane stabilising medications such as tricyclic antidepressants and gabapentanoids may help selected patients. Conservative measures such as jaw stretching, occlusal splint therapy, and NSAIDs or paracetamol for flare-ups may continue if beneficial, but irreversible dental or surgical interventions are discouraged.

Referral pathways

Referral is guided by the presenting features and underlying contributing factors:

• Refer to a dentist for significant teeth wear or fractures, and restoration failure
• Refer to an oral medicine specialist for persistent TMD with pain or locking
• Refer to a sleep physician for significant snoring, apnoea, or sleep disturbance
• Refer to a specialist physiotherapist for jaw-specific rehabilitation and postural retraining
• Refer to a psychologist or pain specialist for complex cases or psychosocial distress

Communication and reassurance

Patients often seek confirmation that their pain is real and manageable. Validating the experience while emphasising the benign and self-limiting nature of most TMD is key. Explain that bruxism is a common behaviour and that pain can occur without visible joint or imaging abnormalities, as pain arises from the somatosensory system rather than structural damage alone. Emphasise that most jaw pain improves with conservative care, and the goal is to limit jaw overuse, relieve symptoms, and restore function.

Key points

• Bruxism is common and often benign; unless it represents a sign of an underlying condition that warrant treatment
• Bruxism should be managed if causes jaw pain and dysfunction or dental damage.
• Screen for known risk factors of bruxism: alcohol, caffeine, SSRIs, stimulants, tobacco, obstructive sleep apnoea, reflux, ADHD, insomnia, and stress.
• Use a simple three-question TMD screen (pain, dysfunction, locking) to guide diagnosis.
• Prioritise conservative care for TMJ: education and reassurance, habit reversal, jaw stretching, occlusal splint therapy when indicated, and short NSAID or paracetamol course.
• Adopt a biopsychosocial framework for chronic orofacial pain and avoid unnecessary imaging and irreversible dental or surgical intervention.