Medically reviewed by Brittany Ferri, PhD
Understanding mouth guards and occlusal splints for teeth grinding and clenching
One of the most frequently recommended treatments for bruxism—commonly known as teeth grinding or clenching—is the use of mouthguards. These removable dental appliances, often referred to as occlusal splints, night guards, bruxism guards, or bruxism splints, are designed to cover several or all of your upper or lower teeth. They are generally made in a dental lab from hard acrylic resin and molded from an impression of your teeth.
Mouthguards come in various designs, each serving different purposes and varying in effectiveness and potential side effects. This article aims to provide a comprehensive overview of mouthguards, delving into their mechanisms, types, effectiveness, and key considerations.
What is the Purpose of Using a Mouthguard for Bruxism (Teeth Grinding / Clenching) and Does it Work?
Although mouthguards have been prescribed for decades, their exact mechanism remains somewhat unclear and controversial. Some theories, like the elimination of occlusal interference, have been debunked, while others, like increasing awareness of the habits and altering sensory perception of the jaw muscle, still have to be proven. These are some of the reasons why physicians prescribe mouthguards:
Protect Teeth
By covering the teeth or preventing them from touching, mouthguards protect against the wear and tear caused by grinding and clenching. This helps prevent enamel damage, fractures, and other dental issues. However, tooth wear can still occur even with a mouthguard, especially if you have an acidic diet, acid reflux, or dry mouth. Also, it’s important to note when the grinding or clenching happens. Wearing a mouthguard at night won’t help if the grinding primarily occurs during the day.
Reduce Muscle Activity
Wearing a mouthguard can help reduce the activity of your chewing muscles, like the temporalis and masseter muscles, which are involved in grinding and clenching. If you’ve ever worn a mouthguard before, you know how it can feel a little weird. Well, this difference in sensory perception also changes the feedback from your mouth’s receptors, making you more aware of your grinding or clenching habits and helping to reduce these behaviors and the accompanying muscle activities.
This effect, sometimes known as the “novelty effect,” is usually short-term and most noticeable when the splint is new. Over time, your muscles may get used to the splint, reducing this novelty effect. One study actually suggests that using the mouthguard intermittently can be more effective than continuous use for this reason.
Spread Occlusal Load
A mouthguard can help distribute the pressure from clenching or grinding evenly across all your teeth, reducing stress on any single tooth or joint. This can protect your teeth and gums from the harmful effects of long-term grinding or clenching, and help alleviate symptoms like pain, headaches, or gum issues.
Occlusal Interference Elimination
Initially, splints were believed to work by smoothing out occlusal interferences (misaligned bites) that caused bruxism. However, recent research has debunked this theory, showing that bruxism isn’t related to bite issues, or how your teeth or jaws fit together. Today, using jaw repositioning splints or undertaking orthodontic treatments to address bruxism is discouraged since several studies have confirmed that bruxism is a behavior driven by the central nervous system, not your dental features.
Are mouthguards effective for bruxism?
Mouthguards can reduce grinding and clenching in the short term (the first few weeks to months of use), but its long-term effectiveness varies. While some patients continue to benefit over extended periods, others may find the effects diminish over time, as the initial response gradually wanes when the body gets used to it.
A 2007 Cochrane review found that mouthguards are no better than control in reducing bruxism activities, sleep metrics, and tooth wear. A 2017 review also concluded that there are no significant differences in effectiveness between occlusal splints and other therapies like Transcutaneous Electrical Nerve Stimulation (TENS), Cognitive Behavioral Therapy (CBT), and pharmacological treatments.
However, some individual studies have reported significant reductions in bruxism activity, particularly in patients with severe bruxism. This suggests that mouthguards don’t work uniformly for all patients. In fact, in one randomized controlled trial using polysomnography (detailed sleep study), a few reported improvement, while others saw no change or increased their grinding/clenching.
The impact of mouthguards on symptoms like pain, headaches, and neck and shoulder tension also varies. Some patients report significant relief, while others see little to no change. Individual variability in treatment response is a significant challenge, especially since there’s no way of knowing in advance who will benefit from it and who won’t.
There are several newer types of mouthguards which have shown better efficacy:
For individuals with suspected sleep apnea, mandibular advancement devices (MADs) often show greater and statistically significant reductions in bruxism activity and improvements in sleep quality. This improvement is attributed to better airflow during sleep, which leads to less apnea/hypopnea episodes and fewer sleep disruptions. However, MADs can also lead to more complaints of muscle and TMJ pain due to their size and mechanism of pushing the jaw forward. Another type of mouthguards, biofeedback splints, though not yet widely available, have also shown greater reductions in bruxism activities and more durable effects compared to regular splints.
Given the variation in response, it’s important to note that mouthguards might not be suitable for everyone. Some patients may find that wearing a splint increases their clenching and grinding, exacerbating their symptoms. If a splint causes or increases pain, it is crucial to consult with your dentist for an alternative solution.
Read next: What type of mouthguard should I use?
