A bite appliance is a removable dental device, often custom-made, that fits over the upper or lower teeth to treat or prevent various oral health issues. It acts as an interface between the upper and lower dental arches, stabilizing the bite relationship between the teeth and jaw joint. Appliances are generally worn to manage muscular tension, protect teeth from damaging forces, or guide the lower jaw into a more comfortable position. The overall goal is to restore balance to the system involving the teeth and jaw muscles.
Categorizing Bite Appliances
The term “bite appliance” is broad, encompassing devices categorized by material and function. Appliances designed for heavy use are often crafted from hard acrylic, offering superior durability and a precise fit for stabilization. These rigid devices, frequently called occlusal splints, are used when therapeutic changes to the bite are the goal.
Other appliances are made from softer, more flexible materials, such as soft vinyl, and are commonly known as nightguards. These softer versions primarily serve as a protective barrier to cushion the teeth and absorb the forces of grinding. A significant distinction exists between custom-made appliances, fabricated in a dental laboratory from impressions, and generic over-the-counter options. Boil-and-bite devices offer a less precise fit and are not recommended for long-term therapeutic use due to their potential to create an unstable bite relationship.
Primary Reasons for Usage
A common reason for prescribing a bite appliance is to manage bruxism, the involuntary clenching or grinding of the teeth. Wearing a protective appliance, typically a nightguard, creates a physical shield between the upper and lower teeth. This prevents excessive wear and potential fracture damage to the natural tooth structure and existing restorations.
Bite appliances are also a standard conservative treatment for Temporomandibular Disorders (TMD), conditions causing pain and dysfunction in the jaw joint and surrounding muscles. For TMD, a stabilization splint helps relieve muscle soreness by promoting a relaxed jaw position and reducing inflammation within the joint. Additionally, a specific type of bite appliance, a Mandibular Advancement Device (MAD), is used to manage mild to moderate obstructive sleep apnea or snoring. The MAD works by gently holding the lower jaw and tongue slightly forward, which helps to keep the airway open during sleep.
The Mechanism of Action
Bite appliances achieve therapeutic results primarily through the even distribution of occlusal load. This action spreads the force of biting across the entire dental arch rather than concentrating it on specific teeth or areas of the jaw joint. This even contact minimizes stress on the temporomandibular joint (TMJ) and reduces the potential for localized tooth damage.
The appliance also promotes muscle relaxation through a neuromuscular effect by altering the sensory feedback from the teeth. By creating a smooth, flat surface, the device prevents the teeth from locking into their habitual, strained position. This disrupts the nerve signals that trigger clenching, allowing hyperactive jaw muscles to rest.
Certain designs, known as repositioning appliances, are engineered to guide the mandibular condyle—the rounded end of the lower jaw—into a more favorable alignment within the joint socket. This repositioning relieves joint pressure and encourages the healing of soft tissues within the TMJ.
The Fitting and Maintenance Process
Obtaining a custom-fitted bite appliance begins with a thorough diagnosis by a dental professional to determine the appropriate appliance type. Impressions of the upper and lower teeth are taken, using traditional molds or digital scanners, to capture the exact contours of the mouth. This precise data is sent to a dental laboratory, where the appliance is fabricated to the dentist’s specifications, often taking up to two weeks.
Once the custom device is ready, the patient returns for an initial fitting. The dentist makes minor adjustments to ensure the appliance seats comfortably and establishes the correct bite relationship. A wearing schedule, such as nightly use for bruxism, is established, and follow-up appointments are scheduled to monitor adaptation and refine the fit.
For maintenance, the appliance should be cleaned daily using the following steps:
- Use a soft toothbrush and non-abrasive soap or toothpaste.
- Thoroughly rinse the appliance.
- Allow the appliance to air dry completely.
- Store the appliance in its protective case to ensure longevity and hygiene.