The role of dental splints

Key takeaways:

• Dental splints (mouthguards) are custom-made devices worn over the teeth to reduce muscle strain, protect teeth, and cushion the jaw during clenching or grinding.

• Splints are usually worn during sleep, but may also be helpful in high-stress moments during the day — they should not be worn 24/7.

• Splints are not a cure — and they don’t always help with TMD, especially if used in isolation. They work best when combined with self-management strategies.

• Proper fit is essential — a poorly fitted splint can worsen symptoms or affect how your teeth come together, especially if used long-term.

• Use consistently for the first 3 months to assess benefit, and consult your dentist for ongoing adjustments or concerns.

• JawSpace helps you build a foundation by addressing contributing factors like clenching, stress, and muscle tension — making splints more likely to be helpful if needed.

Splints & TMD:

Temporomandibular Disorders (TMD) and teeth grinding, known as bruxism, can cause strain on the jaw muscles, joints, and teeth. Utilising a mouthguard (“dental splint”) can provide help for these conditions by offering support to the jaw, reducing strain on the joint/muscles for TMD, and preventing or reducing tooth damage in significant bruxism.

A dental splint, sometimes referred to as an occlusal splint or bite guard, is a customised dental device that helps alleviate various issues related to TMD and bruxism. Typically composed of hard or soft acrylic materials, a splint fits over the upper or lower teeth, forming a barrier that prevents direct tooth-to-tooth contact which helps reduce the muscles’ potential to stay in a fully contracted (‘tense’) state where they may also cause load to the TMJ. 

If a splint has been prescribed to you, it's recommended to wear it as specifically instructed by your dentist. Generally, a splint is worn during sleep, but if engaging in stressful daytime activities, such as working to a tight deadline at a computer when you cannot voluntarily control habitual clenching or grinding, using a splint can be beneficial to provide a physical reminder not to clench/grind. It should not, however, be necessary to wear a splint 24 hours a day and nor is it advisable to do so as this can risk changing the way your teeth meet together. 

Historically there are some splints that clinicians advised to wear full-time for TMD but these are not now routinely recommended. Due to uncertainty about splints’ level of effectiveness they are generally now thought of as an additional and later stage of treatment and should only be introduced after a firm foundation of self-management has been established and should not seek to produce irreversible changes in the bite.

In the early stages (first 3 months) of use of a splint it is important to use it consistently (every night) to get the benefit from it. Once things have stabilised, and feel like they have improved you can experiment a little by using it less frequently. The mechanism by which splints work, other than protecting the teeth from damage from grinding in bruxism, is unclear but it is thought that it involves some of the following for relieving pain:

• Support and cushioning for the jaw: By offering a cushion between the upper and lower teeth, a splint helps absorb the forces generated during clenching or grinding, relieving pressure on the jaw muscles and joints, and thus reducing associated TMD and bruxism pain and discomfort.

• Reducing strain on the temporomandibular joint (TMJ) and reducing muscles from remaining in a fully contracted state (‘tense’) for long periods of time

Early evidence from brain scan data suggests splints may also change the way pain signals from the face flow through the emotion, movement/body position and pain systems in the brain. How they do this and exert a beneficial effect is yet to be determined.

However, splints do have their limitations. They don’t train the jaw muscles to relax or avoid harmful actions like clenching, grinding, or moving the jaw side-to-side (“shuffling”). 

Additionally, they may not address all the factors that combine to cause TMD or bruxism.

It’s also important to note that a poorly fitted splint can cause more harm than good. A splint that doesn’t fit properly may not provide the desired relief and could potentially worsen symptoms. Similarly if you have ongoing dental problems such as ‘gum disease’ or tooth decay it’s important these are resolved before using a splint as it is possible that a splint can make untreated gum disease or tooth decay worse. Therefore, it’s crucial to have a splint custom-made by a dental professional to ensure a proper fit and effective symptom management.

Moreover, if your splint becomes uncomfortable or seems to be worsening your TMD symptoms, it’s essential to stop using it. Once you stop using it, please contact your dental professional to have it checked, remade, refitted, or replaced as soon as possible. Even a well-fitted splint can sometimes require adjustments over time to ensure continued effectiveness and comfort.

Remember, while splints can provide relief for some people, they’re usually just one part of a broader TMD and bruxism care plan. Engaging with JawSpace first gives you a strong foundation — helping you understand your symptoms, build healthier habits, and reduce contributing factors. If a splint is recommended later, you’ll already be in the best possible position to benefit from it.

References:

1. Eberhard, D. "The Efficacy of Anterior Repositioning Splint Therapy Studied by Magnetic Resonance Imaging." The European Journal of Orthodontics, vol. 24, no. 4, 2002, pp. 343–352. https://doi.org/10.1093/ejo/24.4.343.

2. Singh, B. P., et al. "Occlusal Interventions for Managing Temporomandibular Disorders." Cochrane Database of Systematic Reviews, 2017. https://doi.org/10.1002/14651858.cd012850.

3. The TMJ Association. "Splints." The TMJ Association, 2023, https://tmj.org/living-with-tmj/treatments/splints/.

4. Ernst, M., et al. "Effects of Centric Mandibular Splint Therapy on Orofacial Pain and Cerebral Activation Patterns." Clinical Oral Investigations, vol. 24, no. 6, 2020, pp. 2005–2013. https://doi.org/10.1007/s00784-019-03064-y.

5. Lickteig, R., et al. "Successful Therapy for Temporomandibular Pain Alters Anterior Insula and Cerebellar Representations of Occlusion." Cephalalgia, vol. 33, no. 15, 2013, pp. 1248–1257. https://doi.org/10.1177/0333102413491028.

6. Lotze, M., et al. "The Cerebral Representation of Temporomandibular Joint Occlusion and Its Alternation by Occlusal Splints." Human Brain Mapping, vol. 33, no. 12, 2012, pp. 2984–2993. https://doi.org/10.1002/hbm.21466.

7. Lickteig, R., et al. "Changes in Cortical Activation in Craniomandibular Disorders during Splint Therapy – A Single Subject fMRI Study." Annals of Anatomy, vol. 194, no. 2, 2012, pp. 212–215. https://doi.org/10.1016/j.aanat.2011.10.006.

8. Busse, J. W., et al. "Management of Chronic Pain Associated with Temporomandibular Disorders: A Clinical Practice Guideline." BMJ, vol. 383, 2023, article e076227. https://doi.org/10.1136/bmj-2023-076227.