An anterior repositioning splint is a custom oral appliance designed by dental professionals. This removable device is fabricated from durable acrylic resin to fit precisely over a patient’s upper or lower teeth. It addresses jaw joint issues, especially those related to the temporomandibular joint, which connects the jawbone to the skull. The splint influences the lower jaw’s position for better joint alignment.
Purpose and Indications for Use
Temporomandibular joint disorders (TMDs) are conditions affecting jaw joints and muscles, causing pain, clicking, or limited movement. A common issue addressed by an anterior repositioning splint is anterior disc displacement with reduction. This occurs when the small, fibrocartilage disc, which acts as a cushion within the jaw joint, slips forward from its normal position.
When the mouth opens, the displaced disc temporarily moves back into its proper place, often causing a clicking or popping sound. Upon closing, the disc may slip forward again, often producing another sound. While disc displacement can occur without symptoms, treatment with an anterior repositioning splint is considered when it causes pain, discomfort, or restricted jaw movement. The splint resolves these symptoms by guiding the jaw into a position where the disc remains properly aligned.
Mechanism of Action
The anterior repositioning splint functions by guiding the lower jaw, or mandible, into a forward position. This is achieved through built-in ramps or guides on the splint’s surface that interact with the opposing teeth as the patient closes their mouth. By directing the mandible forward, the splint helps the articular disc within the temporomandibular joint return to its correct alignment between the condyle (the rounded end of the lower jawbone) and the temporal bone of the skull.
Holding the jaw in this new position recaptures the displaced disc, keeping it stable and properly seated. This alignment alleviates clicking or popping sounds and reduces pain by minimizing pressure on sensitive tissues behind the disc. Over time, this stable environment allows strained ligaments and joint tissues to adapt and heal. The splint creates a temporary “home base” for the jaw, reducing joint stress and improving function.
The Treatment Process
The treatment process begins with a diagnosis by a dentist, often involving a clinical examination and MRI to confirm disc displacement. If indicated, dental impressions or digital scans of the patient’s teeth are taken to create a custom appliance that fits precisely. The splint is fabricated in a dental laboratory, ensuring it accommodates the individual’s oral anatomy.
Once the splint is ready, the patient returns for a fitting appointment where the dentist delivers the appliance and makes adjustments for comfort and proper jaw positioning. The dentist provides a wearing schedule, often for most of the day, including sleep and eating, for 3 to 6 months. Initially, eating may be challenging, and a softer diet recommended. Regular follow-up appointments monitor progress, adjust the splint, and guide the patient on gradually reducing wear time once symptoms stabilize.
Post-Splint Therapy Considerations
Anterior repositioning splint therapy is considered “Phase I” treatment, stabilizing the temporomandibular joint and alleviating immediate symptoms like pain and clicking. While effective in recapturing the disc and promoting joint healing, maintaining the jaw forward can alter a patient’s bite. A posterior open bite may develop after splint therapy, meaning the back teeth no longer meet when the jaw is in its new, stable position.
Once the joint is stable and symptoms have resolved, “Phase II” therapy is recommended to establish a permanent, stable bite in the new jaw position. This phase creates a harmonious relationship between the teeth and the adapted joint position. Phase II treatments include orthodontics (e.g., braces) to realign teeth, or prosthodontic procedures like dental crowns to build up tooth surfaces. Bite adjustments, also known as equilibration, may also fine-tune chewing surfaces. The anterior repositioning splint is a temporary measure, preparing the jaw for more definitive long-term dental solutions.