Jaw Locking or Won't Open Fully Singapore: Causes & What To Do
Quick answer
Jaw locking — when your jaw suddenly won't open as wide as normal, gets stuck open, or catches painfully when you try to open or close — is a sign that the cartilage disc inside your jaw joint has significantly displaced. It needs prompt dental attention. Unlike simple jaw clicking, jaw locking indicates the joint problem is progressing.
In the meantime: - Do not force the jaw open — you can worsen the disc displacement - Eat soft foods only (soups, porridge, soft noodles) - Apply a warm compress to the jaw for 10 minutes several times a day - Take anti-inflammatories (ibuprofen) if not contraindicated **At the dentist:** They will assess the severity, may order a CBCT scan, and typically start with an occlusal splint and physiotherapy.
Types of jaw locking
I've been through enough dental procedures in Singapore to know that the information gap between what clinics tell you upfront and what you actually need to know is significant. Here's what I've learnt.
Closed lock (most common): You wake up or notice your mouth won't open as wide as usual — typically less than two finger-widths. It may catch or pop when you push through. Usually accompanied by jaw pain.
Open lock: Rarer — your mouth gets stuck open, usually after opening very wide (yawning, at the dentist). The disc has completely displaced and the jaw is stuck in front of the joint. This requires manual reduction by a dentist or doctor.
Intermittent catching: The jaw sticks briefly or requires a specific movement to unlock. This is an early warning sign before full locking develops.
What causes jaw locking?
The jaw joint has a small disc of cartilage that normally moves smoothly as you open and close. In TMJ disorder, this disc gradually shifts out of position. Early on this causes clicking. As the displacement worsens, the disc can block jaw movement entirely — causing locking.
Common contributors: Longstanding untreated teeth grinding Jaw clenching under stress Previous jaw injury or trauma Naturally loose jaw ligaments Inflammatory arthritis affecting the joint (less common)
What to do right now
If your jaw is locked open: This is an acute situation. Go to the nearest A&E or dental emergency clinic. A dentist can manually guide the jaw back into position (painless with local anaesthesia).
If your jaw won't open fully: Book a dental appointment urgently — aim for within 48 hours. In the meantime: Do not force the jaw open — you can worsen the disc displacement Eat soft foods only (soups, porridge, soft noodles) Apply a warm compress to the jaw for 10 minutes several times a day Take anti-inflammatories (ibuprofen) if not contraindicated
At the dentist: They will assess the severity, may order a CBCT scan, and typically start with an occlusal splint and physiotherapy. Surgery is rarely needed for jaw locking.
Cost in Singapore
$300–$2,000
TMJ treatment is generally not Medisave-claimable as a dental procedure. A&E visit for jaw lock: $100–$200 at polyclinic or restructured hospital.
Key takeaways
- Jaw locked open = dental emergency — go to A&E or an emergency dental clinic
- Jaw won't open fully = urgent dental appointment within 48 hours
- Do not force the jaw — this worsens disc displacement
- Jaw locking is a progression from untreated clicking/grinding — earlier treatment prevents it
Other patients also asked
Find dental clinics with jaw pain and TMJ experience near you.