What’s the Difference Between Mouth Guards and Splints?

Up to 30% of people suffer from bruxism (teeth grinding). Regular and forceful grinding of teeth can lead to more severe issues, such as joint and arthritic disorders. This makes the choice between a mouth guard and an occlusal splint—often called a TMJ splint or night guard—crucial for your dental health.

Mouth guards are quite common these days. Chances are you know someone who pops one in before bed or a high-contact sport. However, they serve a completely different purpose than splints, despite looking quite similar.

This guide explains the key differences between mouth guards and splints, from their design and materials to cost and effectiveness, helping you make the right choice for your specific needs.

Purpose and Uses

Night guards work primarily as protective barriers between your upper and lower teeth. They create a cushioning effect that blocks direct tooth-to-tooth contact during sleep. This protective layer helps distribute biting forces across a larger surface area, significantly reducing damage to your dental enamel. Without this protection, teeth grinding can lead to cracks, chips and excessive wear over time.

Splints, however, are therapeutic devices specifically designed to address temporomandibular joint (TMJ) disorders, which affect the joints that connect the jawbone to the skull. It can cause pain, difficulty opening and closing the mouth, and other symptoms like clicking or popping noises in the jaw. These splints do more than just protect your teeth: they actively work to stabilise your jaw, helping your jaw muscles relax while evenly distributing pressure across your teeth. Splints can also reduce tension on your joints and guide your jaw back to its ideal position.

The treatment goals highlight the key differences between these devices. Mouth guards focus on managing symptoms without addressing the underlying cause of bruxism. They effectively reduce damage from grinding but don’t change your jaw positioning. Splints take a more active approach by repositioning your mandible (lower jaw), potentially addressing the root cause of certain jaw disorders. By moving the condyle (the rounded end of your jaw bone) away from the fully seated joint position, these splints can reduce pressure on sensitive tissues, resulting in less pain and improved jaw function.

For patients dealing with stress-related teeth grinding, both devices offer valuable benefits. However, if you’ve been diagnosed with a TMJ disorder, unstable bite, or muscle pain in your jaw, a properly fitted splint will likely provide better results than a standard mouth guard.

Design and Materials

Traditional mouth guards were once made from hard acrylic materials that tended to warp during manufacturing, making a precise fit challenging. Thankfully, modern dental technology has largely solved this problem. Today’s devices use advanced materials including specially formulated hard resins combined with acrylics for patients with severe teeth grinding.

Newer thermoplastic materials now offer better comfort without sacrificing shape retention. These materials contour more precisely to your teeth compared to older designs. Some occlusal splints cleverly combine materials, using a hard acrylic outer layer for durability with a thermoplastic base for comfort.

The design differences between these devices are quite distinct:

• Mouth guards typically feature a flat biting surface that covers all your upper teeth. This design helps spread the pressure of grinding across a larger area, protecting individual teeth from excessive force.
• Splints come in two main types:

1. Permissive splints that allow your jaw joints to separate completely while maintaining even tooth contact.
2. Directive splints that specifically position your jaw joints and disc assemblies to correct alignment issues.

For patients seeking the best of both worlds, newer biocompatible soft resins enable 3D printing of flexible splints that offer strong protection while remaining comfortable and resistant to fracturing.

Conditions Treated

Occlusal splints specifically target TMJ disorders, which affect approximately 10 million Americans. These therapeutic devices help with various TMJ-related conditions, including disc derangements, arthritis and joint inflammation. They work by reducing mechanical stress on your jaw joints by altering how force is distributed when you bite down.

Mouth guards, on the other hand, mainly play a protective role. They shield your teeth from damage during sports activities and protect dental enamel from the harmful effects of teeth grinding. If you participate in high-contact sports like football, basketball or hockey, wearing a mouth guard is essential to prevent chipped or knocked-out teeth.

For those suffering from sleep-related problems, custom-made splints may provide relief for mild sleep apnea by positioning your lower jaw and tongue forward, helping to keep your airways open during sleep. They can serve a similar purpose for chronic snoring, though the research on their effectiveness isn’t conclusive.

Recent studies have shown promising results for TMJ splints in reducing TMJ-related headaches. By treating the underlying jaw joint issues, patients often experience fewer migraines and tension headaches, with decreased intensity when they do occur.

Comfort and Wearability

When it comes to mouth guards and splints, comfort varies significantly between devices and even between different types of the same appliance. Custom-fitted dental appliances feel much better than anything you’ll buy off the shelf. Patients consistently report higher comfort levels with professionally designed splints compared to generic options. This makes sense: a personalised fit means less irritation against your gums and tongue.

The material of your appliance greatly affects how it feels in your mouth. Soft splints made from silicone or rubber-like materials spread biting forces more evenly because they have more give. This makes them particularly helpful if you experience muscle spasms. Hard acrylic splints might feel less comfortable initially, but often provide better results for certain conditions.

Where the appliance sits in your mouth also affects comfort. Splints typically cover both your upper and lower teeth at the same time, while night guards usually protect just one arch. About 90% of patients choose upper night guards because they find them more comfortable and they interfere less with their tongue.

Your comfort directly impacts whether you’ll actually wear your device consistently, making proper fitting and material selection crucial for successful treatment.