It has three basic functional and structural parts: the hinges, the frame, and the lock (or doorknob). When all the parts are properly aligned and working well, the door can easily be closed with the gentle push of a finger. We all know of doors that do not work this way. You might have a door that you must lift the knob a little to make it close into its hasp, or a door with a “sticky frame” that requires a tug or push to open or close, or a door with noisy hinges that rattle or squeak. Would you expect a door with rusty or loose hinges to work better if you changed the lock or trimmed the frame? Of course not! Unless the hinges are stable, the correct position of the lock and frame is uncertain. Likewise, if the lock and/or frame are misaligned or “sticky,” the hinges will become stressed and strained until they bend, break, or become loose. The problem door remains a nuisance because it does not correctly open, shut, or lock.
So how is a door fixed to work well for a long time? By correcting one variable at a time. First, evaluate the hinges to ensure they are strong, stable, and well-aligned. Next, check the door in its frame. Plane it or adjust the trim so there are no “catches,” it is “squared,” and it closes evenly within the frame. Lastly, place the lock/doorknob so it is centered and aligned within its hasp. You should now be able to open and close the door with just a finger or two.
Just like the body, age will take its toll on a door. With time and use, the door may sag and become less easy to close or lock. The door becomes a slight nuisance because it must be lifted a little to close properly. This may not seem significant because it can still open and close, it just requires a little extra effort. But what happens over time? The hinges become stressed, the lock seems to get a bit worse, and the frame sticks. Sometimes when the weather is hot and humid, the door (especially wooden and fiberboard ones) will swell and become problematic, requiring an extra tug to open or close. Next season, when the air is dry again, the door may work “better” but not fully return to what it used to be. The point is that the door may require minor maintenance to keep it working well, but if neglected, future repairs become more complicated and expensive.
Also, and most importantly, each of the three parts of the door has its own individual qualities. Unless all three parts work harmoniously, there will be problems in one, two, or all three parts.
The Face. In reference to the door analogy, consider the TMJs as the hinges, the bite (meshing of the teeth) as the lock/doorknob, and the alignment between the upper and lower jaws as the way the door fits within its frame. Yes, there are other parts of the face such as the muscles, nerves, gums, and tongue. These structures are also important, but they usually have a secondary role relative to the TMJ Trinity.
Long-term facial and jaw functional stability depends upon proper alignment and structural health within the TMJ Trinity.
