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Neuromuscular Dentistry is the science of dentistry that embodies accepted scientific principles of patho-physiology, anatomy, form and function. NMD objectively evaluates the complex relationship between teeth, temporomandibular joints and the masticatory muscles in order to achieve ati occlusion that is based on the optimal relationship between the mandible and the skull — Neuromuscular Occlusion. The goal of the Neuromuscular Dentist is to relax the muscles controlling jaw position to establish a true physiological rest position upon which treatment considerations are based.

In summary; NMD is the science of occlusion encompassing not only the teeth, but the objective evaluation of the status and function of the jaw muscles and joints — before, during and after treatment — to achieve the optimal result.

Occlusion is the foundation of dentistry. It is of key importance in the success of every major dental procedure. Occlusion is affected by a triad of factors — the teeth, the muscles and the temporomandibular joints. Traditional dentistry has focused on the teeth — what might be called "one-dimensional" dentistry. Neuromuscular Dentistry (NMD) is a term that has been applied to the additional consideration of the "second & third dimensions" — muscles and TM joints.

The limited time in the dental curriculum makes it difficult enough for schools to prepare dentists to deal with the teeth. Muscles and joints typically get a cursory once- over. As dentists go into practice, it is not uncommon to hear them say that they have done procedures "by the book" and yet have less than satisfactory results. Or, that a case is so complex they refer the case out rather than treat it themselves.

Neuromuscular Dentists commonly report that taking muscle and joint status into consideration aids them in optimizing treatment, minimizing the times that they are "surprised" by less than ideal outcomes, and gives them the added insight needed to treat complex cases. There is a significant body of literature published over the past 35 years that supports the efficacy of neuromuscular dental principles.

Muscles of the face and neck are often "programmed" (propriocepted) to control head and mandibular posture in a way that accommodates occlusion, even though that particular occlusion may be less than ideal. The Neuromuscular Dentist wants to relax these often tense muscles to find their true resting state and establish the occlusion at that position. It is extremely difficult to voluntarily overcome this proprioception, so "TENS" is used. A secondary use of low frequency stimulation is to achieve drug-free pain relief of pain of muscular origin.

Myotronics TENS products, the Clinical Myomonitor and the Home Treatment unit BNS-40, are backed by a history of safe, effective use since 1966. The only fixed-rate device of its kind that provides true bilateral, simultaneous stimulation, the Myotronics products provide stimulus at a fixed rate of once every one and one-half seconds (or 40 times per minute).

The Myomonitor's "3rd electrode" ensures safe and simultaneous stimulation of masticatory muscles. In addition, the stimulation of the Myomonitor propels the mandible upward from rest position and registers a physiologic occlusal position with ease and accuracy. The Model J5 Myomonitor, with its two sets of leads, offers the ability to stimulate four sites simultaneously. The second lead set is most often used when it has been determined that there are postural influences on the occlusion. Being able to relax both masticatory and cervical/upper thoracic muscles simultaneously saves valuable time for the office and the patient while insuring optimal relaxation for occlusal diagnosis. Fail-safe circuitry and the fixed low frequency rate provides the ultimate in safety.

The state of the teeth and the joints very often cause the muscles to accommodate. Evaluation of the hard tissue alone does not provide insight to the true status of the occlusal system. This is why the Neuromuscular Dentist uses objective, scientific documentation methods in the comprehensive evaluation of occlusion. Through the use of jaw tracking, electromyography and joint sound recording, a complete analysis of the function (or dysfunction) of the masticatory system is accomplished.

The data produced through jaw tracking has three important roles. First, is to permit the dentist to study mandibular action dynamically by recording and replaying traces representative of the mandibular path of opening and closing. This can reveal, in a highly precise fashion, a number of anomalies otherwise difficult to discern. One example is a sudden slowdown of mandibular velocity, invisible to the eye but often an alert to a clicking joint. Second, the jaw tracking device records the relationship of the mandible to the skull with great precision, information useful in the diagnostic process, and in taking a neuromuscular bite registration. The third application of jaw tracking is to record and verify that patient's closure to centric occlusion is on a neuromuscular (physiologic) trajectory.

Myotronics developed this science in 1971 and has led the way in its improvement ever since. The Myotronics patented "sensor array" at four ounces is the lightest available, assuring that the patient will not become tired and that the sensing module does not interfere with mandibular function. The unit is remarkably free of interfer­ence from inadvertent patient movement or nearby metal objects. The software makes operation simple and provides powerful capabilities in evaluation and patient education.

This is another field that was pioneered by Myotronics with its inception of the first commercial dental SEMG unit in 1981. The Company has led the way since by producing a series of advanced EMG technologies in the dental and medical fields. Accurately processing the minute signals detected through the skin is a technical challenge requiring complex circuits that reject extraneous electrical "noise". The Myotronics technology has become the "gold standard" in the dental and medical fields. The authors of the definitive clinical SEMG text in the medical field chose the Myotronics SEMG technology in their book Introduction to Surface Electromyography. The Myotronics system allows you to record up to eight muscle sites simultaneously, and play them back in a variety of ways for study and patient education.

ESG is most commonly called "sonography" and sometimes "joint vibration analysis". It utilizes computer based vibration sensitive transducer technology that quickly and non-invasively records joint sounds and vibrations originating in the temporomandibular (TM) joints. The patient wears a lightweight headset that positions two sensors over the joints. The technician instructs the patient to open and close, and in just a few minutes valuable information about joint function is captured for analysis.

Bone transmission of sound is so rapid that unilateral study of joint sound with a stethoscope may not even discern which side the sound is coming from. Further, sounds studied in this manner are subjective and not documented. Data captured by means of sonography not only record joint sounds from both TM joints simulta­neously, the information can be played back at will. The dentist can analyze this recorded information in a number of ways that may yield additional insight regarding joint status and joint function. The test can be used as a very quick assessment of joint status and to document patient response to treatment.

Introduced in 1989, the Myotronics ESG is the only system to incorporate transducers calibrated to a vibration measurement standard. These high quality devices are capable of picking up even small sound vibrations from the tissue overlying the TM joints — diagnostic sounds that less sensitive systems fail to detect.

To learn more about Neuromuscular Dentistry, please contact Spa Dentaire Laval. Scientific articles are available upon request.

You can also visit Myotronics website at www.myotronics.com