I do often see patients complaining about their jaws. They mostly have pain in their jaws or muscles or headache. In many cases a mouthguard, also called bite, is a good solution. Other cases where it might be needed is if you are clenching or grinding down your teeth in order to protect them. Moreover there are specific mouthguards for snoring, sport and sleep apnea.
Today we will talk about the one used for bruxism. When you grind or clench your teeth, we talk about bruxism and it is usually an activity caused by some kind of stressor. Bruxism often cause muscle soreness or headache (especially in the morning) and often some jaw pain close to the ears. The reason is the overtrained masticatory muscles, like the one you feel the day after going to the gym.
Since stress is one of the main factors, try reducing it as much as you can as a first step. Then your dentist will check for any malocclusion ( if your teeth are not straight) or a filling/crown that is too high and finally if you are biting unevenly. In all these cases your body will try to rebalance your bite by grinding down the culprit filling/crown/tooth which is not in balance with the other teeth, but because it might take months or years to grind it down, you might develop pain in the mean while by this new extenuant activity.
A mouthguard is a device made of an hard material which fit perfectly your upper or lower teeth and then have a slightly flat surface on the opposite side which will be in contact with the opposite arch. It works because it rebalance your bite, it kind of reset how you bite and since one of the two jaws will be able to bite on a new surface which will force your muscle to be stretched in a more comfortable position,you will feel better. Most of the patients usually have immediate relief after only few days, but of course the mouthguard need to be correctly adjusted in order to achieve this result. Over the counter mouthguards are usually not enough or even harmful and your problem might get worse, since they are often too soft, acting as a chewing-gum which will make you overtrain your teeth or not balanced, which will aggravate the problems.
Which means that in order to make the right mouthguard for you, the dentist have to spend time to check what the problem is in the first place and only later an impression of your teeth and your occlusion (how you bite) is recorded.
On the next appointment the bite will be checked again with the new mouthguard on and a new control after few days is performed where new adjustments might be needed. If everything goes fine, only small adjustments might still be necessary once in a while (usually once per year) since the bite will be consumed as well.
But in order for the bite to work all these steps are necessary.
If you still have pain, you might either have a different problem which is not completely jaw related (e.g. a neck injury) or the problem is at an advanced stage where surgery and/or orthodontic treatment is needed.
Is then your mouthguard for life? In most cases not really, once the problem is identified, you can try to move your teeth or grind down/reconstruct specific areas of your teeth in order to mimic the occlusion obtained with the mouthguard, otherwise the intermitted use of a mouthguard (only few nights per week or months) might be enough.