What is bruxism?

Bruxism: Definition, Diagnosis, and Management

Bruxism is defined as the repetitive jaw muscle activity characterized by clenching or grinding of teeth, which can occur during sleep (sleep bruxism) or while awake (awake bruxism). 1, 2

Types of Bruxism

• Sleep bruxism - occurs during sleep and is characterized by rhythmic or non-rhythmic jaw muscle activity 1
• Awake bruxism - occurs during wakefulness and is typically characterized by clenching of teeth 2

Etiology

The exact cause of bruxism is multifactorial and not fully understood:

• Central factors appear to be the primary regulators rather than peripheral factors 1
• Stress, anxiety disorders, and genetic predisposition are dominant contributing factors 3
• Sleep bruxism may serve protective physiological functions such as maintaining airway patency or stimulating saliva flow 2
• In children, prevalence rates vary widely from 13% to 49% 4

Clinical Manifestations and Consequences

Bruxism can lead to several clinical problems:

• Masticatory muscle hypertrophy and tenderness 1
• Tooth surface loss and fractures of teeth or restorations 2
• Hypersensitive or painful teeth 1
• Loss of periodontal support 2
• Temporomandibular disorders and headaches 1, 5
• Implant and restoration failures 1

Diagnosis

Diagnosis of bruxism involves multiple approaches:

• Patient reports and clinical interviews 2
• Clinical examination showing signs such as:
  • Excessive tooth wear facets (indicating bruxism) 6
  • Muscle hypertrophy 1
  • Scalloped tongue or linea alba on buccal mucosa 2
• Intraoral appliances to detect wear patterns 2
• Definitive diagnosis of sleep bruxism requires electromyography and video recording in a sleep laboratory 3

Management

Management is indicated when bruxism causes problems and is typically directed toward:

• Protection of teeth and restorations 1
• Reduction of bruxism activity 1
• Pain relief 1

Treatment Options:

1. Oral appliances (occlusal splints):

   • Primary purpose is to protect dentition from damage 2
   • May help reduce muscle activity 2
   • Recommended for patients with bruxism, particularly when tooth wear is evident 6

2. Behavioral approaches:

   • Relaxation exercises can improve bruxism symptoms 3
   • Biofeedback techniques 2
   • Improvement of sleep hygiene 2

3. Physiotherapy:

   • Specialized physiotherapy can improve muscle tension, pain, and restricted movement 3
   • Recommended particularly for patients with temporomandibular disorders related to bruxism 6

4. Pharmacological interventions:

   • Limited evidence for long-term effectiveness 1
   • Botulinum toxin (Botox) injections to masticatory muscles may reduce bruxism frequency, though concerns exist about potential adverse effects 2, 3

5. Psychological approaches:

   • Cognitive behavioral therapy for stress management 2
   • Particularly important when bruxism is associated with anxiety or stress 3

Important Clinical Considerations

• There is currently no treatment that permanently "cures" or "stops" bruxism 1
• Irreversible occlusal adjustments have no evidence basis in bruxism management 2
• Available scientific evidence does not support the view that bruxism is a direct cause of pain, which should be considered when managing patients 5
• For children, physiotherapy and psychotherapy are recommended approaches 4
• In cases where bruxism is associated with sleep disorders like obstructive sleep apnea, addressing the underlying sleep condition may be necessary 6

Monitoring and Follow-up

• Regular dental check-ups to assess progression of tooth wear 2
• Periodic evaluation of oral appliances for fit and effectiveness 6
• Assessment of pain levels and masticatory function 5