The ideal bite splint for patients who clench depends on the underlying cause of the clenching. There are multiple causes of jaw clenching:
- Stress: The relationship between emotional stress, anxiety and jaw clenching is well established.
- Medications: Notorious offenders include stimulants like caffeine and SSRI antidepressant medications.
- Jaw injury: Jaw and muscle sprain/strain (JAMSS) occurs with direct jaw trauma, whiplash, prolonged dental procedures, intubation and many other situations. This can trigger muscle guarding, jaw tension and clenching.
- Temporomandibular joint (TMJ) disorders: The two main types of TMJ disorders are those involving the joint and those involving the surrounding muscles. There is a strong association between TMJ disorders and jaw clenching.
- Tension headaches: There is also a close relationship between tension headaches and jaw clenching. The relationship is so intertwined that it is often hard to tell which condition causes the other.
- Sleep bruxism: Jaw clenching and teeth grinding while asleep is referred to as “sleep bruxism.” While there may be no symptoms, some patients experience jaw pain and headaches that gradually diminish during the day.
Bruxism is defined as a repetitive activation of the jaw muscles, and can include jaw clenching, teeth grinding and thrusting of the jaw. It is not a disorder, but rather describes a behavior that is a risk factor for oral health consequences.
There is a subtle but important difference between treating teeth grinding and jaw clenching: Teeth grinding treatments focus on protecting the teeth, whereas jaw clenching treatment addresses jaw muscle tension.
Jaw Clenching Pain
Not all of your patients’ jaw clenching will result in pain, but when it does, you should take it seriously. The jaw muscles open and close thousands of times a day and can generate hundreds of pounds of force. With jaw clenching, the forces on the jaw can be six times greater than the force generated when eating. This can cause strain on the TMJ and surrounding muscles.
If a patient’s jaw clenching is causing symptoms such as jaw pain or headaches, it is important to provide the patient with the care they need. Studies indicate that acute jaw pain, when left untreated, is a key risk factor for developing a chronic pain condition, such as a TMJ disorder.
Dental Bite Splint Types
There are several different types of dental bite splints. Here are some ways to differentiate between them:
- Soft vs. hard splints: Soft splints are made of a material that is boiled and formed to the teeth, and can be sold over the counter. Hard splints are made of resin or hard plastic and are custom-fitted to the teeth. Soft splints do not balance the forces of the jaw and can sometimes make bruxism worse. A 2020 study published in Clinical and Experimental Dental Research showed about 87% of patients who purchased a soft boil-and-bite splint for themselves had incorrectly fashioned the splint, making it ineffective for clinical use.
- Anterior bite vs. full-coverage splints: An anterior bite splint leaves the posterior teeth exposed, whereas a full-coverage splint covers all the teeth. The anterior bite design is optimized for jaw clenching because it completely inhibits posterior teeth contact and activation of the jaw muscles. Full-coverage splints are designed for long-term use, and their primary purpose is to protect the teeth from grinding. Because there is contact with the posterior teeth, muscle function and forces are not as affected.
- Stabilization vs. repositioning splints: Stabilizing splints are meant to stop the destructive forces that occur with teeth grinding. Repositioning splints are designed to change the position of the jaw joint, and can be prescribed to address joint clicking.
- Permissive vs. non-permissive splints: A permissive splint will allow the position of the jaw to glide unimpeded over the biting surface into the most comfortable position. A non-permissive splint will limit the movement of the jaw into a defined relationship. Typically, stabilization splints are permissive and repositioning splints are non-permissive.
- Temporary vs. long-term splints: A temporary splint can be used in situations where jaw clenching is transient, such as with a jaw sprain or strain. Often, the pain associated with jaw clenching can be resolved in two to four weeks with proper conservative care and temporary splinting. Long-term splints are usually needed in cases of sleep bruxism or when jaw repositioning is needed.
The Best Bite Splint for Clenching
While the best bite splint for jaw clenching depends on the underlying conditions listed previously, there is one type of bite splint that addresses many conditions. In a mechanical sense, anterior disclusion devices like the NTI-tss Plus® or NTI OmniSplint® are the most effective for jaw clenching because they prohibit contact of the posterior teeth and can limit the negative impact of jaw activity.
If long-term use is anticipated, as in the case of sleep bruxism, a full-coverage guard like the NTI OmniSplint is the most appropriate choice. Even in this case, a short-term anterior disclusion device like the NTI-tss Plus can be used if there is any jaw pain involved with the clenching. If the jaw clenching is related to a problem in the joint, a repositioning device may be a more appropriate choice.
A temporary, custom bite splint is appropriate in situations where the underlying condition can be addressed in two to four weeks. In addition to cases of jaw injury, this timeframe includes the amount of time it takes to address emotional stressors, change medications, or see a specialist for definitive care. The temporary splint can also be used as a bridge solution for jaw pain until a long-term splint can be fabricated. For additional, non-dental measures, patients can try analgesics and hot or cold therapy.