There are patients that seem to get better on an occlusal appliance, just to settle in after a period of time and then get worse again. Patients who clench fall into this category, the appliance seems to disrupt the clenching or lessen the issue enough that the muscle symptoms subside. Over time they seem to adapt to the appliance and the issue returns. I also have patients that have joint concerns that would dictate one appliance design and also have muscle signs and symptoms that would be best treated by a different appliance design.
In these circumstances I have found that fabricating two different appliances, based on different principles and having the patient alternate can be a great solution. For patients with clenching as a habit, or where the majority of the issue is muscular we use the appliance variation to control muscle force. We do know that when we alter a patient’s vertical dimension of occlusion there is a reduction of muscle force they can apply. this reduction is temporary and they will adapt and the forces will go back up. If the two designs have different VDO’s we can use this to our advantage to control muscle symptoms.
In patients with Joint issues that require posterior bite support we can fabricate a full coverage soft appliance to lessen the joint load and reduce inflammation and symptoms. If these same patients have muscle symptoms or clench a soft appliance will activate the muscles, so we make them a full coverage hard appliance. I have found that if patient’s can alternate between the two they can keep both their joints and their muscles int he adaptive range. I have also found that there is something about an appliance they temporarily interrupts the habitual occlusal patterns, so if we can keep it feeling “new” we can benefit.
How often to alternate the patient and I figure out with trial and error. I have patients that do every other night, and I also have patients that wear one appliance predominantly, and use the other for a night or two when they feel muscle tension or joint tenderness coming on, and then can switch back. If you have some of these challenging patients give this a try, and remember to fee them for both appliances.
For More Information on Appliances: Occlusal therapy: Appliances and Equilibration Online Seminar