Circumstances that Cause TMD (Continued-#2)

The second circumstance, or more properly, set of circumstances that cause TMD is technically referred to as “Functional Malocclusion”.  Let’s see if I can describe functional malocclusion in a way that will make sense to the reader who has no training in the medical sciences.

Think of the chewing mechanism as a finely engineered and manufactured machine.  Actually, everyone on the planet owns a highly engineered and manufactured chewing mechanism as part of their body.  But this chewing mechanism has not been manufactured by the German or Japanese automakers. It was manufactured as a result of millions of years of trial and error development under divine guidance.

So we can compare the human chewing mechanism to a finely tuned BMW automatic transmission made to the highest tolerances.  What do you think will happen if some gremlin got inside that transmission and started breaking or bending some of the teeth on the gear wheels.  What if that gremlin actually removed some of the teeth on the gear wheels or completely removed one of the wheels inside the transmission.   How do you think that transmission would run.?  What effect would that once finely engineered transmission have on the automobile?  Would the car run at all?  Would it make strange grinding noises.  Would the transmission heat up and eventually totally come apart?

The chewing mechanism in the body also has teeth.  The chewing mechanism is also made up of bone, cartilage, muscles, nerves, and blood vessels all working together at the direction of the central nervous system, (Brain).  Similar to an automobile transmission, when the teeth in the chewing mechanism are broken, missing, or not located in the correct location it will eventually cause damage and eventual total destruction of the entire chewing mechanism.  This is what happens when the teeth do not fit together properly.  And when they do not fit together properly to the degree that it causes destruction of other parts of the chewing mechanism, it is called “functional malocclusion”.

The Temporomandibular Joint, (TMJ) is an integral and very important part of the chewing mechanism.  And second only to the teeth themselves, one of the most important features of the chewing mechanism.  Without the TMJ’s you would not be able to chew, talk or swallow.  The lower jaw would not move at all. The health and well being of the TMJ’s are integral to our survival, just as much as the heart and lungs, and the hip and knee joints are for locomotion.

It has also been discovered that the TMJ’s are very susceptible to damage by acute and chronic overloading just like the hips and knees.  In fact, the TMJ’s are MORE susceptible to damage due to overloading than knees and hips.

Functional malocclusion, (teeth fitting together) is the second most common cause of overloading the temporomandibular joints leading to chronic inflammation within these joints.  And as you have learned earlier, chronic inflammation of the TMJ’s directly causes all the terrible symptoms.

Functional malocclusions come in many types and varieties.  It is a fact that our current dental school curriculum does not come close to covering and teaching all that should be known to recognize and treat functional malocclusions.  That is why some dentists go beyond dental school and become specialists and even ad a medical degree to their education.  The dental specialists that acquire special training in treating functional malocclusions are Oral and Maxillofacial Surgeons and Orthodontists.

It is beyond the scope of this blog to discuss more about functional malocclusions other than to clarify malocclusions can be the malposition of the teeth themselves or the malposition of the entire upper and/orlower jaw.  That is why functional malocclusions are a very important part of the training of Oral and Maxillofacial Surgeons.

Overloading the TMJ’s due to functional malocclusions causes inflammation within the joints, which in turns causes the disparate symptoms of TMD.

Our next installment will cover the third category of circumstance that create inflammation within the temporomandibular joint, TRAUMA.

Until then.