What is the cause of a 6-7/10 diffuse, dull, aching pain on the right side of the face, from the outer ear to the upper teeth, alleviated by ibuprofen and aggravated by cold water, with associated duller hearing, following recent food poisoning and dehydration?

Temporomandibular Joint Disorder (TMD)

This patient most likely has temporomandibular joint disorder (TMD), which is the most common cause of referred otalgia and facial pain in this distribution, particularly given the continuous dull ache from ear to jaw, aggravation by cold water, and recent history of dehydration that may have triggered jaw clenching or muscle tension. 1

Clinical Reasoning

The presentation strongly points to TMD based on several key features:

• Location pattern: Unilateral pain from the outer ear down to the upper teeth following the jawline is classic for TMD, as the mandibular branch of the trigeminal nerve has intimate anatomic relationships with the TMJ capsule 1, 2
• Pain quality: The diffuse, dull, aching character (6-7/10) matches TMD rather than the sharp, shooting, electric shock-like pain of trigeminal neuralgia 3
• Timing: Continuous pain since onset (not paroxysmal attacks lasting seconds to minutes) rules out trigeminal neuralgia, glossopharyngeal neuralgia, and SUNA/SUNCT 3
• Associated symptoms: Duller hearing on the affected side is commonly reported with TMD due to proximity of the TMJ to the ear canal 1, 2
• Aggravating factors: Cold water sensitivity suggests dental/TMJ involvement rather than neuropathic pain 3

Why This Isn't Trigeminal Neuralgia

Trigeminal neuralgia would present with paroxysmal attacks lasting 2 seconds to minutes with refractory periods between attacks, sharp shooting electric shock-like pain, and triggers like light touch, washing, or cold wind 3. This patient has continuous dull aching pain, which is inconsistent with classic trigeminal neuralgia.

Potential Contributing Factor: Recent Dehydration

The recent food poisoning with dehydration and vomiting may have contributed to TMD onset through:

• Jaw clenching during nausea/vomiting episodes 4
• Electrolyte imbalances affecting muscle function 4
• Stress and muscle tension during acute illness 5

Immediate Management Approach

Continue NSAIDs as first-line therapy since ibuprofen 400-600 mg is already providing partial relief and has superior efficacy for TMD pain control 1, 4. The current dosing (3-4x daily) is appropriate and within safe OTC limits 6.

Additional Conservative Measures:

• Patient education: Avoid aggravating factors including hard/chewy foods, wide jaw opening (yawning), gum chewing, and clenching 3, 4
• Jaw rest: Soft diet for 1-2 weeks 7
• Heat application: Warm compresses to the affected area 15-20 minutes, 2-3 times daily 4
• Self-care techniques: Gentle jaw stretching exercises and massage of masticatory muscles 3, 4

Physical Examination Priorities

Perform TMJ examination immediately by:

• Direct palpation over the TMJ: Place fingers just anterior to the tragus and palpate for tenderness (hallmark finding) 1
• Assess for crepitus: Listen and palpate during jaw opening and closing 1
• Evaluate range of motion: Note any limitation in opening, though full range doesn't exclude TMD 1
• Palpate masticatory muscles: Check masseter and temporalis for tenderness 4, 5

Red Flags Requiring Urgent Evaluation

While TMD is most likely, urgent referral to oral and maxillofacial surgery or ENT within 1-2 weeks is warranted if:

• Any palpable neck mass or lymphadenopathy develops 7, 1
• Mucosal lesions, ulcerations, or induration appear 1
• Progressive neurological symptoms, visual changes, or fever occur 1
• Pain becomes sharp, shooting, or paroxysmal (suggesting neuralgia) 3
• No improvement after 2-3 weeks of conservative management 4

If Conservative Management Fails

After 2-3 weeks without improvement, consider:

• Referral to dentist/oral surgeon for occlusal appliance (hard stabilization splint worn at night) 3
• Physical therapy for jaw exercises and manual therapy 3, 4
• Cognitive behavioral therapy if psychological factors are present 3, 4
• Muscle relaxants (e.g., cyclobenzaprine) for short-term use if muscle spasm is prominent 4

Common Pitfall to Avoid

Do not assume this is dental pathology requiring extraction or root canal without proper TMD evaluation first, as many patients undergo unnecessary dental procedures when TMD is the actual cause 3, 2. The cold water sensitivity may suggest dental involvement, but the distribution of pain and associated ear symptoms point more strongly to TMD.