Segmental Appliances and Risk

In the past few weeks I've had correspondence with three dentists asking about the use of an anterior bite plane appliance like the one pictured here. This appliance is constructed of 2mm Biocryl formed with Isofolan over the maxillary teeth. It was trimmed initially to cover all the maxillary teeth but the molar coverage was removed so that the anterior flat “bite” plane could be flat at the level of the incisal edges.

The only contact the patient can make is against the mandibular six anteriors in all movements and the surface is completely flat relative to those teeth. It takes very little energy to skate around on this surface to any position the patient wants to go to. Since the need to "posture" the mandible in maximum intercuspal position is not necessary, the lateral pterygoids can relax and the mandible can move to wherever the joints determine. In many patients the relief is immediate. That can be a problem.

As long as the appliance is not worn more than eight hours in 24 we do not expect the teeth to move. When we use the appliance with patients who did not come into the office with pain there is very little risk that they will wear the appliance more than recommended. These patients have tender muscles or joints, or restricted range of motion that must be controlled prior to confidently mounting the study casts. If we ask patients, most would say they are wearing it as instructed – they are fine. Patients who present with pain are very different.

If you were in pain and I gave you a device that relieved the pain for you, what would you want to do? Wear it. If I told you to only wear it at night, but it made the pain go away, what would you want to do if you hurt during the day? Wear it. Because you really want to obey my instructions you may begin to rationalize by wearing it a little during the day and “less” at night. Because the appliance makes it stop hurting, you may extend your time “at night” by leaving your pajamas on until the middle of the morning or going to “bed” much earlier.

You may learn that if you don't touch your teeth together during the “day” things feel better so you wait to put teeth together until “night.” The problem with pain is that relieving it makes everything seem like a rational action. Patients who present with pain are at a very high risk for wearing the appliance in a way that may promote tooth movement because they want to use it.

I teach the use of the anterior bite plane appliance. It is far the most prescribed appliance I use. However, in patients who present with pain, they never wear it for very long.

If the ABP is being used in a patient who presented with pain to diagnose muscle from joint problems, the diagnosis is followed by fabrication of an appropriate appliance. Because muscle problems make up such a high percentage of patients who present with pain, that appliance is usually a full coverage lower appliance that I call a “Tanner” after Dr. Henry Tanner who taught me how to use it. (The design of the full arch appliance you use and the arch on which it is applied will be determined by your training and experience.)

The point is, if the patient presented with pain and responded to the ABP therapy, get them in a full arch appliance ASAP. The Anterior Bite Plane is not a treatment appliance when the patient presented with pain or has pain when the appliance is not in their mouth. These patients require a full arch appliance so they can wear it.

Email me if you are interested in a workshop for the design, fabrication and insertion of a full arch appliance. We moved the fabrication of the ABP to the Occlusion in Clinical Practice workshop because of its importance as a diagnostic and protective device. Maybe it's time to bring back a redesigned Advanced Occlusion course with the full arch appliance in it ... what do you think?