A mouth guard is a dental appliance that is designed to create a barrier between the top and bottom sets of teeth, preventing direct contact between them. Although the material feels hard and durable, it is softer and less dense than a tooth, so damage caused by teeth grinding can be kept to a minimum.
It also brings the bottom jaw forward and lessens tightening of the jaw muscles during teeth grinding in sleep, all of which help to reduce the symptoms and health consequences caused by teeth grinding.
For years, mouth guards have been considered one of the cheapest, if not the most effective way of managing teeth grinding. Ever since they appeared on the market, multiple studies have been carried out to determine their effectiveness, balanced with the adverse effects they can cause.
While mouth guards may be the management method of choice for teeth grinding problems in the short term, the side effects may eventually outweigh the advantages of using them in the long run, raising the question of whether or not mouth guards should still be considered a solution for teeth grinding.
Using mouth guards becomes questionable when treatment only revolves around symptom alleviation rather than taking the necessary steps to find the underlying causes of the problem. Recent evidence has linked obstructive sleep apnea (interrupted breathing) and teeth grinding during sleep.
In fact, Continuous Positive Airway Pressure (CPAP) treatment has proven capable of reducing the frequency of teeth grinding. Given that there are many potential causes of teeth grinding, mouth guards only serve as a temporary solution in the long run.
Dry mouth and hypersalivation (too much saliva) are the most common complaints of those who wear a mouth guard. Dry mouth is frequently seen when mouth breathers use an oral appliance designed with a narrow opening, which allows a gradient of air flow to build up and eventually creates an air stream.
The continuous stream of air entering the oral cavity then dries out the mouth. On the other hand, hypersalivation may occur when the mouth tries to adapt to a new device inserted into the mouth during sleep. As a result, people who are new to wearing a mouth guard may experience excessive salivation while sleeping and wake up to find that they are drooling.
Although a mouth guard helps to protect the teeth from becoming flattened and cracked, it is not without disadvantages. Wearing a mouth guard all night means constantly exerting light pressure to the jaw muscles to support the mouth structures and keep the airway open.
As a result, people who grind their teeth may experience sore gums when they wake, which may last throughout the day. So it is unlikely that they will wear their mouth guard every night if it causes extreme discomfort and pain, because it would make little or no difference to their quality of life.
Some people experience jaw stiffness while getting used to a new mouth guard. This is because our jaw muscles are unaccustomed to being stretched and having unusual pressure exerted on them for prolonged periods of time.
The stiffness is comparable to the experience and aching sensation of getting back to the gym after a long break. Typically, the stiffness may last for a couple of days before it gradually subsides. Sometimes – albeit rarely – it may also cause the patient difficulty in opening and closing the mouth, affecting their speech and eating.
So far, the side effects mentioned are relatively mild and mostly they disappear within a couple of days. However, there are some side effects that may lead to permanent changes to the dental structures and alter the shape of the face.
One of these side effects is jaw displacement or the change of the lower jaw’s position after wearing a mouth guard for an extended period of time. Once the jaw has adapted to being brought forward, it tends to remain in the adjusted position and cause a jaw protrusion or prognathism.
As if it were not bad enough, jaw displacement may also lead to the misalignment of the upper and lower teeth when the jaw is closed. A case report published in the April 2010 issue of The Journal of Craniomandibular Practice stated that a patient used a mouth guard for six months under the instruction of his dentist, which led to unstable alignment of his wisdom teeth.
Another less common, but severe, side effect is loosening of the teeth. This is especially likely when the mouth guard is not custom-made since a shop-bought mouth guard doesn’t tend to fit as well, and has a higher chance of causing discomfort. Loosening of the teeth is more likely to happen to those who have pre-existing dental problems, such as weak gums or damaged enamel. A poorly fitting mouth guard only worsens and speeds up the development of dental complications.
From an expense point of view, a custom-made set of mouth guards costs €350 on average, depending on the type. Most mouth guards last two to three years, with durability that varies from one person to another. These mouth guards may not be affordable for those looking for a long-term cure.
If patients lose or break their mouth guard, their teeth may become vulnerable to damage while waiting for a new set to be made. In addition to this, patients who cannot afford a customised mouth guard might resort to purchasing an off-the-shelf one, which can exacerbate the damage, since these over-the-counter mouth guards are not moulded to the individual mouth.
In conclusion, it is worth noting that a mouth guard may not be the best solution to teeth grinding, and there are several approaches dentists should take first. Management should be based on treating the underlying cause instead of just offering a superficial solution.
Before prescribing a mouth guard, advise patients to have a sleep study carried out, ruling out other causes, such as sleep apnea. By addressing the underlying issue, teeth grinding can be cured since the impulse to grind will have been removed.