ON4
This appliance is useful after acute injury or after condylar neck fracture that has healed. This appliance is best fabricated on the maxilla with full coverage and full occlusion. Condylar neck fractures are usually treated by ligating the mandible to the maxilla in centric occlusion. The problem is that all of the muscular attachments are medial to the condyle. If the oral surgeon does not take x-ray to demonstrate reduction of the fracture, it will not heal properly. The condyle heals in a medially displaced position. The patient now has a posterior open bite.
Do not try a positioned appliance in this situation as all of the nociception in the joint and muscular attachments and ligaments have been altered. A flat plane appliance will allow the patient to stabilize in whatever altered position with whatever altered range of motion that they evolved to. The exception to this would be a patient who had a pre-existing osteoarthritis at the time of injury. In any scenario involving condyle neck fracture (which is fairly common), minimize interferences on your appliances.
The specifications for this appliance are at least two mm thickness. It should be fabricated from models that have been mounted on an Acculiner/Acculator taken with a phonetic bite.
Who Should Wear This Appliance
In acute injury where orthotic therapy has been instituted within weeks of the trauma, without complete disc dislocation, or history of TM joint pathology. That means that the capsular and discal ligaments have been stretched and are therefore inflamed. The purpose of this appliance is to provide a stable, level plane for healing of muscle, tendons and ligaments as well as reducing compression of the injured joints. This is the patient that you suspect you will be weaning off the appliance.
Most dental surgeries would recognise the appliance called a Michigan Splint. This appliance is very similar in design however there are subtle differences which set The ON4 apart from the Michigan. Call our team at Functional Orthotic Design today and find out more about the differences between appliances and appliance therapy that can reward you with outstanding results .