WHAT SHOULD YOU KNOW

The most common treatment for temporomandibular disorders is a splint − or, as one dentist put it, "Everybody needs magic plastic." If you are being recommended to get a splint you should know all about them before you agree to the treatment.

BASIC INFORMATION

Definition: An occlusal (refers to the position of the teeth or “bite”) splint is a removable dental appliance that covers several or all of the upper or lower teeth.

Types: There are several distinct types of occlusal splints.

• Stabilization or flat plane splint. This splint covers all the upper teeth and its flat surface is intended to help reduce tooth grinding and relax your sore jaw muscles. However, it does not prevent tooth clenching because the lower teeth can still contact it. Therefore, in some patients, their condition can be aggravated by the splint.
• Modified Hawley splint. This splint fits on the upper jaw and makes contact with only the six lower front teeth. Thus it keeps the back teeth from touching and prevents both clenching and grinding. It is generally worn only at night because constant wear may allow the back (posterior) teeth to shift.
• NTI-tss (Nociceptive Trigeminal Inhibition Tension Suppression System). The NTI appliance fits on the upper front teeth and is designed to prevent tooth clenching and grinding. However, because it fits on only a few teeth, it places a great deal of stress on them and that can be harmful. Also, because of its small size, if it comes off during the night, there is danger that it could be swallowed or aspirated.
• Repositioning splint. This splint is used to move the lower jaw either forward or backward. It is intended to put the jaw into a new position and therefore it can cause permanent changes in the bite. It is a more invasive form of splint treatment.

Materials Used: Occlusal splints are typically constructed of hard acrylic resin. The resilient or soft type is less durable, more difficult to adjust and harder to keep clean. In some patients it may encourage clenching and grinding and therefore increase the symptoms.

Beyond the basic information, what do you need to know in order to decide if a splint is right for you?

WHAT DOES THE SCIENCE SAY?

Occlusal splints are among the most popular non-surgical means by which dentists treat pain in the jaw muscles and TMJ. However, studies to evaluate the effectiveness of splint therapy have produced inconsistent results. Here's a summary of current research:

•  Evaluation of the short-term effectiveness of education vs. an occlusal splint for the treatment of myfacial pain of the jaw muscles,  in JADA, Vol 143: pgs 47-53, January 2012.  In this study the authors compared the use of an occlusal splint provided without accompanying education with an education program that informed the patients that excessive muscle activity could cause their pain and focused on avoiding oral habits, limited use of the jaw and eating a soft diet. After 3 months, the education program was slightly more effective in reducing spontaneous muscle pain, and there was no difference in pain-free mouth opening, headache and pain on chewing between the two groups. Although the authors conclude that an education program may therefore be more effective than an occlusal splint, in this study they did not include the usual education program that should accompany splint therapy. Conclusion: further studies are needed to determine if an education program plus splint therapy would be better than either used alone.
• The 2010 National Institutes of Health TMJ disorder brochure says, “Stabilization splints are the most widely used treatments for TMJ disorders. Studies of their effectiveness in providing pain relief, however, have been inconclusive. If a stabilization splint is recommended, it should be used only for a short time and should not cause permanent changes in the bite. If a splint causes or increases pain, stop using it and see your health care provider.”

• A 2010 Systematic review and meta-analysis of randomized controlled trials evaluating intraoral orthopedic appliances for temporomandibular disorders found hard stabilization appliances, when adjusted properly, have good evidence of modest efficacy in the treatment of TMJD pain compared to non-occluding appliances and no treatment. Other types of appliances, including soft stabilization appliances, anterior positioning appliances, and anterior bite appliances, have some RCT evidence of efficacy in reducing TMJD pain. However, the potential for adverse events with these appliances is higher and suggests the need for close monitoring in their use.

• A 2007 Cochrane Database of Systematic Review study states, "there is insufficient evidence to either support or refute the use of occlusal splints for treating patients with tooth grinding or clenching during sleep (sleep bruxism).”
• A 2004 Cochrane Database of Systematic Review study concluded "there is insufficient evidence either for or against the use of stabilization splint therapy for the treatment of temporomandibular pain dysfunction syndrome."

Because studies so far have shown inconsistent results at best, you should be especially wary of having a repositioning splint. Because the effects of the use of this type of splint are permanent, prolonged use (over 6 weeks) raises the risk of changes in the bite, long-term damage to the joint, and increased pain, requiring further treatment and possibly including surgery.

In summary, it is wise to be informed and educate yourself before you agree to any recommended treatment.

QUESTIONS YOU SHOULD ASK YOUR DENTIST

There isn’t an accepted standard of practice for splints. Here is a list of questions you should ask:

• What is the splint going to do (flat plane or repositioning), and why are you recommending this kind to me?
• Are you recommending this splint to decrease my pain, reposition my bite or both?
• What are my other options?
• What happens if my pain gets worse while wearing the splint?
• What happens if I develop an open bite (teeth no longer touch)?
• What proof do you have that this splint will help?
• Do I wear the splint during the day, night, or both?
• How long do I have to wear the splint to feel improvement?
• If the splint doesn't help, what are the next steps?
• How many follow-up treatments will be necessary and how much each visit cost?
• Will insurance cover the cost of the splint and the follow-up treatments?
• Must I sign a financial contract with you to begin treatment?

Your dentist may make you agree to a range of other “services” as a condition for providing the splint. These other services may include various modes of massage/physical therapy, injections, braces and/or crowns. These are all added costs. Some dentists require that you sign a contract for splints and/or a whole treatment “package” before they will make and fit your splint.

If you decide to get a splint, what is the procedure?

After your initial consultation, the dentist will make an impression of your teeth.After the splint is made, the dentist will fit and readjust it. You will be expected to wear it at the recommended times (all day, only at night, both), and to come in for follow-up appointments to check on your bite and have the splint readjusted, if necessary. Your dentist will advise you how to care for the splint.

What is the cost of a splint and treatment?

Since splints can cost up to thousands of dollars, including initial examination and fitting. You should expect to pay for follow-up visits. Insurance often does not cover this treatment, so be sure to check with your insurance carrier in advance.

Over-the-counter splints

Over-the-counter splints are occlusal splints that are sold in stores. They are made of a type of plastic that softens when warmed and you can then mold the splint to fit over your teeth.  Such splints should never be used because it is not possible to obtain an exact fit and therefore they can cause permanent changes in the bite by moving the teeth.

Athletic mouth guards

These mouth guards are used by people engaged in contact sports to protect the teeth from injury and are not designed for use in patients with TMJ problems.

What is an Aqualizer?

The Aqualizer is a soft plastic bite appliance filled with water, the use of which is based on the idea that jaw muscle pain is caused by an unbalanced bite. By containing a liquid, the Aqualizer is supposed to automatically rebalance the bite because the fluid level can vary depending on the degree of tooth contact. The problem with this appliance is that it is based on a false premise -  that myofacial pain can be caused by the manner in which the teeth touch each other rather than by what the patient may be doing with their teeth. Rather than working by "rebalancing the bite", the appliance works because the patient senses that biting against the fragile plastic  will cause it to break and therefore it may cause them to stop clenching and grinding.

ADDITIONAL INFORMATION

Additional splint Q&A’s can be found on TMJArchive as well as an article by Dr. Christian Stohler, Dean at Maryland Dental School in Baltimore MD, Occulsal Bite Splints: A Help for Many But Not Everyone.

Thanks to our volunteer, Laurie who researched the current literature for this article. It was reviewed for accuracy by Dr. Daniel Laskin, the TMJA's clinical consultant.