Hi,
It appears you are having problems with the Temporomandibular joint secondary to ?Bruxism (grinding of the teeth). Night guard would prevent the same but in certain occasions you might not benefit from that. Please do consult your Dentist/Faciomaxillary surgeon and your physiotherapist.
Few Tips:
1. Reduce stress if any
2. Avoid foods and drinks that contain caffeine, such as colas, chocolate, and coffee.
3. Avoid alcohol. Grinding tends to intensify after alcohol consumption.
4. Avoid chewing on pencils or pens or anything that is not food.
5. Avoid chewing gum as it allows your jaw muscles to get more used to clenching and makes you more likely to grind your teeth.
6. Relax your jaw muscles at night by holding a warm washcloth against your cheek in front of your earlobe.
7. Try taking muscle relaxants (such as Methacarbamol)
Regards
OHNS2010
Sounds like TMJ. I would reconsult your dentist for further recommendations for this unresolved jaw pain, etc.
Do you have a TMJ splint or a bruxism guard you use at night?