Jaw pain when you open your mouth is usually from irritation of the joint or muscles that move your jaw, but it can also come from teeth, arthritis, or (rarely) infection. You should see a dentist or doctor urgently if the pain is severe, your jaw locks or won’t open normally, or you have fever, swelling, chest pain, or trouble breathing.

What’s most likely going on?

When your jaw hurts mainly while opening, common culprits include:

  • TMJ/TMD (jaw joint disorder) – Irritation of the temporomandibular joint or the small disc inside it; often causes pain when opening wide, chewing, or yawning, sometimes with clicking or popping sounds.
  • Tight or overworked jaw muscles – From clenching, grinding your teeth (especially at night), chewing gum a lot, or holding tension in your jaw during stress.
  • Jaw strain or minor injury – Opening really wide (big yawn, dental visit) or a small hit to the chin or side of the face can inflame the joint or muscles.
  • Dental problems – Deep cavities, abscesses, impacted wisdom teeth, or gum disease can make the jaw area hurt when you open or chew.
  • Arthritis in the jaw joint – Osteoarthritis or rheumatoid arthritis can affect the TMJ, causing stiffness, grinding, and pain when moving your jaw.

Think back over the last few days: big yawn, long dental appointment, lots of stress, new tooth pain, or a small injury can all be clues.

Red-flag signs: get urgent help

Contact emergency care or urgent medical help right away if you notice any of these:

  • Jaw pain plus chest pain, pressure, or pain spreading to your arm, neck, or jaw (could be heart-related, especially if you feel sick, sweaty, or short of breath).
  • Jaw stiffness with high fever , feeling very unwell, or trouble swallowing or breathing (possible serious infection or tetanus).
  • Sudden big swelling of your face or jaw, or one side looks very swollen and hot.
  • You cannot open your mouth more than about two fingers’ width , or your jaw is stuck “locked” open or closed.
  • Recent major injury (car crash, sports injury, punch, fall) with jaw pain or difficulty closing your teeth together (possible fracture or dislocation).

These situations are not for self-care at home.

When it’s okay to start with self-care

If your pain is mild to moderate , came on gradually, and you have no major red flags above, it’s often related to muscle strain or TMJ irritation. Typical “milder” features:

  • Soreness or ache around your jaw, in front of your ears, or in your temples.
  • Pain that gets worse when you chew, talk a lot, or open wide, and eases with rest.
  • Occasional clicking or popping, but you can still open and close.
  • You’ve been stressed, grinding your teeth, or clenching your jaw.

You should still book a dentist or doctor (TMJ-aware dentist, oral surgeon, or primary care) if:

  • The pain lasts more than 1–2 weeks.
  • It keeps coming back.
  • Opening is getting more limited over time.

They can check for TMJ disorders, dental issues, arthritis, or sinus/nerve causes and recommend proper treatment.

Home steps that are usually safe

These ideas are general and do not replace an in‑person exam, but they’re commonly recommended for short-term TMJ or muscle pain:

  1. Rest your jaw for a few days
    • Avoid very wide opening (big yawns, huge bites, loud singing).
    • Stick to softer foods: yogurt, scrambled eggs, soups, pasta, smoothies.
  2. Warmth or cold
    • Try a warm (not hot) pack on the side of your face for 10–15 minutes a few times a day to relax muscles.
 * Some people prefer a cold pack wrapped in a thin cloth for short periods to reduce inflammation.
  1. Jaw relaxation habits
    • Aim for a relaxed “lips together, teeth slightly apart” position; your teeth should not be clenched all day.
 * Notice and gently stop clenching when stressed, driving, working, or gaming.
  1. Over-the-counter pain relief (if safe for you)
    • Short-term use of common pain relievers or anti‑inflammatories can help, if you don’t have reasons to avoid them (like kidney disease, ulcers, blood thinners, or allergies).
    • Always follow the package instructions and, if in doubt, ask a pharmacist or doctor first.
  2. Gentle movement only
    • Avoid forcefully stretching your jaw or “popping it back” yourself.
    • If a clinician later recommends specific TMJ exercises, follow their plan; random intense exercises from the internet can sometimes make things worse.

What a dentist or doctor might look for

In clinic, they’ll usually:

  • Ask when the pain started, what makes it worse, whether it clicks, locks, or has happened before.
  • Check how wide you can open, whether your jaw shifts to one side, and where pressing causes tenderness.
  • Look at your teeth and gums for cavities, abscesses, cracked teeth, or crowded/impacted wisdom teeth.
  • Sometimes order scans (X‑ray, CT, or MRI) if they suspect joint damage, fracture, or disc problems.

Treatments can include bite splints or night guards, physical therapy, stress management, dental work, medications, or—in more severe structural cases—procedures targeted to the TMJ.

Quick checklist for you

Consider these questions and use them as a guide when you talk to a professional:

  • Does the pain happen only when I open wide, or also when resting?
  • Did this start after dental work, an injury, or a very stressful time?
  • Do I wake up with sore jaw muscles or headaches (possible night grinding)?
  • Can I fit three finger-widths vertically between my front teeth when I open as wide as I comfortably can?
  • Do I have tooth pain, swelling in my gums, or bad taste (possible dental infection)?

If you tell me more—like how long it’s been happening, where exactly it hurts (in front of ear, cheeks, teeth), and anything that makes it better or worse—I can help you think through the most likely causes and the kind of specialist to see next.