#98 Bruxism is not the Only Cause of TMD/TMJ

The Oxford dictionary defines bruxism as involuntary habitual grinding of the teeth, typically during sleep. Bruxism is the most common cause of damage and chronic inflammation within the temporomandibular joint, (TMJ). But it is not the only cause.  There are two other causes. In this article, I will discuss the second most common cause which dentists call functional malocclusion.

Functional malocclusion has a very broad definition and description.  It includes problems in the bite that cause functional problems with chewing, speech, breathing, and swallowing.  These problems are not always perceptible by the patient but should be easily identified by a qualified and knowledgeable dentist.  And some of these problems are so severe that they can be easily seen and diagnosed by both patients and doctors from a distance.  This level of functional malocclusion encompasses growth problems of the entire face and considered facial growth anomalies.  As an Oral and Maxillofacial Surgeon, I surgically treated facial growth anomalies of various kinds for 50 years.  It’s not hard to spot these problems.  There are known parameters for normal facial growth.  When the face and jaws grow outside these parameters the esthetics of the face decrease and can usually be spotted from across the room.  These kinds of problems get most of the attention.

 

But even small variations from normal growth parameters of the jaws can cause profound problems with chewing, speech, swallowing and most importantly can cause damage to the TMJ.  Functional malocclusion of the jaws, large or small, is the second most common cause of Temporomandibular Joint Disorder, (TMD).

Unfortunately, not all dentists and orthodontists are knowledgeable enough to detect the less obvious problems with facial and jaw growth.  Very little time is given to educating orthodontists during their specialty training about facial growth, and no time is given to training a dentist about facial growth while in dental school.  Therefore, it is no wonder these doctors frequently miss the opportunity to correctly diagnose facial and jaw growth anomalies, especially when they are of the less obvious variety.

 

The more obvious the facial and jaw growth anomaly the more likely the patient will be made aware of the problem, and the less obvious the facial and jaw growth anomaly, the less likely the patient will even know there is a problem affecting their chewing, speech, swallowing, and temporomandibular joint health.  It is these small deviations of jaw growth problems that cause the second most common cause of TMD.  These relatively small deviations of jaw and facial growth are called CO/CR Discrepancies.

 

Every person on the planet has two bites.  One is called Centric Occlusion, (CO), and the other is called Centric Relation, (CR).  Centric Occlusion (CO) is the position of the jaws when the teeth fit with their best and usually normal interdigitation.  Centric Relation (CR) is when the jaw drops back to the most comfortable and functional position of the jaw joint (TMJ).  Fortunately, most patients can accommodate small differences between CO and CR as they go about daily chewing, speaking and swallowing.  However, some patients do not accommodate relatively small differences well.  When this happens the temporomandibular joints are damaged which leads to chronic inflammation within the joints, which leads to the various symptoms of temporomandibular joint disorder, (TMD).

 

In this scenario the patient is unlikely aware of any problem until the symptoms start to occur.  The first symptom in most cases is a recurrent reciprocal clicking of the jaw joint.  This symptom is usually ignored by the patient because it is not painful and causes no disfunction. It is caused by inflammation within the joint damaging the ligaments of the joint.   This can be ignored for years until one or more of the TMD symptoms begin to appear, first occasionally, then more frequently, and always getting worse over time.

 

Functional malocclusion is the second most common cause of TMD/TMJ.  It is easy to miss the warning signs of functional malocclusion.  Once the damage of functional malocclusion occurs the joint is unable to heal without help.  Decreasing the chronic inflammation within the TMJ and reversing the symptoms of TMD is not difficult to do if the functional malocclusion is properly diagnosed and secondly, the joint is treated by unloading the forces and stresses on the joint adequately.

 

The Urbanek Device and Protocol unloads the TMJ like a set of crutches unloads a damaged and inflamed knee.  It’s all very simple.