What are the possible causes and treatments for pain at the lower jaw bone (mandible)?

Lower Jaw Bone Pain: Causes and Management

Most Common Causes

The most common non-dental cause of lower jaw pain is temporomandibular disorder (TMD), affecting 5-12% of the population, which should be your primary consideration after ruling out dental pathology. 1, 2

Temporomandibular Disorders (TMD)

• TMD typically presents as musculoskeletal pain involving the muscles of mastication, either unilaterally or bilaterally, often worsening with jaw function such as chewing or speaking 1, 2
• Pain may be accompanied by joint tenderness, limited jaw movement, clicking or crepitus, and deviation during opening 2
• TMD is complex and often coexists with other chronic pain conditions and psychological factors like depression 1
• Up to 30% of acute TMD cases may progress to chronic pain if not addressed early 2

Dental Causes

• Acute dental pain (abscess, caries, periodontitis) remains the most common cause overall and requires dental referral 1
• Post-dental procedure neuropathic pain can develop after root canal therapy, extractions, or dental implants 1

Osteonecrosis of the Jaw

• Monitor for jaw swelling and/or exposed mandibular bone, particularly in patients with history of bisphosphonate use, denosumab, radiation therapy to the head/neck, or antiangiogenic medications 1, 3, 4, 5
• Osteonecrosis presents with persistent pain, exposed bone, and may develop fistulas that probe to bone 3, 4
• Incidence is 1-15% in oncology patients receiving high-dose antiresorptives, but only 0.001-0.01% in osteoporosis patients 5

Serious Causes Requiring Urgent Evaluation

• Head and neck malignancy must be considered, especially with unilateral pain, a palpable mass, induration, ulceration, or non-healing lesions in patients over 40 with tobacco/alcohol use 3
• Salivary gland disorders (stones, tumors, infection) characteristically cause pain before eating if a stone is present 1, 3
• Giant cell arteritis must be distinguished from TMD, especially in patients over 50 years old 1

Diagnostic Approach

Critical History Elements

• Timing: onset, duration, periodicity (continuous vs episodic), and relationship to jaw movement or eating 1, 3
• Character: sharp/electric shock-like suggests neuropathic pain; dull/aching suggests musculoskeletal or inflammatory 1
• Associated symptoms: exposed bone, fistulas, fever, difficulty swallowing, changes in vision, or palpable masses 3
• Medication history: bisphosphonates, denosumab, radiation therapy, antiangiogenic agents 1, 3, 4, 5
• Trauma history: recent dental procedures, facial trauma, or jaw surgery 2, 5

Physical Examination

• Palpate the TMJ bilaterally for tenderness and assess jaw opening range and deviation during opening 2
• Examine for exposed bone, ulceration, masses, or fistulas in the oral cavity 3, 4
• Use bimanual palpation for floor of mouth and submandibular areas to assess masses 3
• Palpate for cervical lymphadenopathy which may indicate infectious or malignant processes 3

Imaging Considerations

• Plain films often suffice for initial evaluation 5
• CT or cone beam CT is preferred for evaluating bone lesions and architecture 2, 5
• MRI is the gold standard for detecting TMJ synovitis and evaluating soft tissue structures 2

Treatment Algorithm

For TMD (Most Common Non-Dental Cause)

Cognitive behavioral therapy (CBT) augmented with relaxation therapy or biofeedback provides the greatest pain relief, approximating twice the minimally important difference, and should be first-line treatment. 1, 2

Conservative Management (First-Line)

• Therapist-assisted jaw mobilization and manual trigger point therapy provide substantial pain reduction 1, 2
• Supervised jaw exercise and stretching with or without manual trigger point therapy 1
• Supervised postural exercise 1
• Patient education about self-management and improved self-efficacy leads to fewer symptoms 1, 2
• Usual care including home exercises, stretching, self-massage, and over-the-counter analgesics 1

Adjunctive Therapies

• Hard full coverage stabilization splints worn at night may have some efficacy, though long-term education may be more beneficial 1
• Avoid splints that don't account for occlusion as they can cause tooth movement and malocclusion 1
• Physical therapy shows evidence of effectiveness 1
• LED light therapy with electromagnetic field demonstrated greater pain reduction than cryotherapy in clinical trials 6

Pharmacotherapy

• Over-the-counter analgesics like ibuprofen for symptomatic relief 1, 7
• Insufficient evidence for low-level laser therapy 1
• No benefit demonstrated for Botulinum Toxin in RCTs 1

When to Consider Surgical Intervention

• If functional limitations persist (crepitus, severe limitation in movement) despite conservative management 1
• Arthrocentesis (least invasive lavage under local anesthesia) though results are not maintained 1
• Arthroscopy under general anesthesia for more exploration 1
• Open surgery may increase functionality but relapses are common 1

For Osteonecrosis of the Jaw

Early Stage Management

• Administer broad-spectrum antibiotics for early stage lesions, particularly when signs of infection are present 1, 4
• Use antiseptic mouth rinses (chlorhexidine gluconate or povidone-iodine solutions) at least twice daily until sufficient healing 1, 4
• Daily saline irrigations 1

Moderate to Severe Cases

• Combination of antibiotics with pentoxifylline, tocopherol, and prednisolone shows greater benefit than antibiotics alone 4
• Consider hyperbaric oxygen therapy as adjunct in mild cases 4

Surgical Management

• Refer to oral and maxillofacial surgeon or head/neck surgeon for consideration of hyperbaric oxygen therapy for early and intermediate lesions, debridement of necrotic bone, or external mandible bony exposure through skin 1
• Avoid aggressive debridement unless conservative measures fail 3
• Localized surgical debridement is indicated in advanced nonresponsive disease 5

For Neuropathic Pain (Post-Traumatic or Trigeminal Neuropathy)

• Manage according to standard neuropathic pain guidelines 1
• Carbamazepine is most effective for trigeminal neuralgia with electric shock-like pain provoked by light touch 1
• Consider neurosurgery for poorly controlled trigeminal neuralgia 1

Red Flags Requiring Urgent Referral

Refer within 1-2 weeks maximum to an oral and maxillofacial surgeon or ENT specialist for: 3

• Unilateral jaw pain with palpable neck or jaw mass 3
• Exposed bone or non-healing ulceration 3
• Patients over 40 with unilateral pain, induration, or non-healing lesions, especially with tobacco/alcohol use 3
• Suspected malignancy based on clinical presentation 3
• Suspected salivary stone requiring imaging and removal 3

Important Caveats

• Address psychological factors (depression, catastrophizing) concurrently as they reduce treatment success in TMD 2
• Bacterial biofilm formation in osteonecrosis may interfere with systemic antibiotic efficacy, requiring higher doses or longer treatment courses 4
• Discontinuation of bisphosphonates has not been shown to reverse osteonecrosis, and surgical manipulation may worsen the condition 8
• Avoid excessive jaw movement and recommend soft diet during acute pain episodes 3
• Ensure coordinated communication between primary care, specialists, and the patient's dentist 3