Hi, I have no experience with this myself, but I am an avid Googler because I want to help. Here is one sufferer's advice:
Warm WashclothThis might seem a little too simple, but this is my go-to whenever I'm having pain. All you have to do is soak a washcloth in warm to hot water, depending on the temperature you can handle. Ring the towel out and place it on your jaw for 15-20 minutes before going to bed. This will help relax the jaw muscles and reduce the tension. You can repeat this as often as you'd like, even doing it while studying, reading or taking a bath.
Hot BathIf you clench while you're sleeping, than taking a warm bath before bed could be perfect for you. Often times taking a shower is all we ever do, its quick and easy, but at the end of the day winding down could be your key to a clench-free rest. The warmth from the bath will help to reduce tension all over, including your jaw! Add in the warm washcloth from before and this could become your nightly routine.
General PainkillersWhether it's ibuprofen or aspirin taking an over-the-counter painkiller can often relax the muscles used to clench as well as reduce the pain after a night of clenching. You could even use a PM painkiller (such as Tylenol PM) to help stop you from clenching while you sleep. While this method can be helpful, try not to rely on the painkillers everyday. These should only be used if the clenching is getting out of control, unbearable or interrupting your everyday life.
Jaw MassageThis technique is done by taking both hands and finding where your jaw hurts the most. Once you've found that rub with a medium amount of pressure in circles for 5 to 10 minutes. This helps the jaw loosen up and increase blood flow so any pain from clenching can be reduced.
Hot DrinksSome people swear by it to reduce their clenching. Simply put it's amping up the amount of hot teas and coffees that you drink throughout the day to alleviate pain centered in your jaw. I recommend camomile tea which will relax you and your jaw.
The Wine Cork MethodThis method works best for me and all you need is a wine cork. All you do is find a wine cork, generally 1 to 1.5 inches in height and prop
open your jaw. Place the wine cork in the back of you mouth (if you have a dominate clenching side, on those molars) and hold it there for about
3 to 5 minutes. BE CAREFUL! This could be a choking hazard so DON'T do this laying down, make sure you are upright and aware of where the cork is. If it becomes extremely uncomfortable, remove the cork immediately. I've never experienced any problems with the wine cork method, but being cautious is extremely important.
source:
mishew.hubpages.com/hub/How-to-stop-clenching-your-jaw