Basic Concepts

HomeAbout OC | OC Masterclass Training | Course Schedule | Registration | Accommodations | About Dr. Chan | Study Club | Doctor EducationPatient EducationVision | Research Group | Science | Orthodontics | LaboratoryDr. Chan’s ArticlesGNM Dentistry | Contact Us | Partners | Dr. Chan’s Blog Notes  |  Finding a GNM Dentist

“To create a quieter neuromuscular environment within the stomatognathic complex, the clinician must be able to achieve and measure muscles at rest.  The concept of evaluating every patient from what seems to be a nebulous, fluctuating position is foreign to most dentists.  Yet rapidly advancing technology, expanding knowledge and new clinical techniques can capture these physiologic act for clinical procedures.”

“If we are to optimally treat and prevent pathologies of the teeth, temporomandibular joints, and neuromuscular components of the stomatognathic systems, we must start from a reference of normalcy.  To treat a pathologic dentition to its existing position only invites perpetuation of that tooth pathology.  To reference occlusion to a pathologic neuromuscular system is to invite perpetuation of the muscular dysfunctions.”

Jankelson Text: Page 66.

Physiologic Rest Position

“Physiologic Rest Position [PRP] is defined as that mandibular position in which the various mandibular muscles are simultaneously at their resting length and in balanced tonus with one another.”

“The precise location of PRP, however, has traditionally been a problem in clinical practice because it depends on the complex behavior of muscle.

As a broad rule, in living organisms there are no fixed physiologic absolutes.  At best, there is an ideal norm about which the physiologic norm fluctuates within a normal range.  So it is with rest position.”

[This is what I believe most NM doctors forget….]

“Theoretically, physiologic rest position can be defined as the absolute that will be constant, provide the resting muscle remains in constant equilibrium.  This is the essential requirement of the definition. [I italicized for emphasis].

This equilibrium, however, is in such precarious balance that to assume it exists at any given time or will readily respond when called upon for clinical purposes is physiologically unrealistic… Realistically, physiologic rest must be considered the reference position which will enable the clinician to come as close as possible to providing a favorable occlusal relaxed neuromusculature.”

“The concept of evaluating every patient from what seems to be a nebulous, fluctuating position is foreign to most dentists.”

Yet a rapidly advancing awareness, using the Myotronics K7x technology, expands one’s knowledge and new clinical techniques can be developed and captured to visualize these physiologic acts whether healthy acting mandibular positioning or pathologic acting occlusal positioning can be determined for clinical procedures.


In order to achieve this favorable occlusal relaxed neuromusculature, how do you all believe PRP can be achieved?

Dr. Steven Fisher: “1-2 mm closed on trajectory from most relaxed rest position.  Attained with TENS and verified with EMG.  Both joints should be decompressed and discs recaptured as much as possible.” “Oh…… and posture should be as neutral as possible.”

Dr. Clayton Chan: “Right on Steve!”


If structural force created by parafunctional activity exceeds the structural tolerance of any single component, then it is likely to breakdown. (e.g. Chain with the weakest link).

Structural tolerance is influenced by factor such as anatomic form, previous trauma, and local tissue conditions.

The teeth, TM Joints and muscles will all reflect particular signs or symptoms related to breakdown.  The clinician should identify both the clinical predispositions and actual pathologies and when indicated intercede before additional breakdown occurs.

Crowding, excessive wear, and lingual inclination of lower teeth are frequently the result of neuromuscular hyperactivity.  The muscular hyperactivity is caused when the mandible attempts to free itself from a posteriorly entrapped occlusal position.

This hyperactivity, in turn, results in abnormal wear and positioning of the teeth and the temporomandibular joints.

Optimal Occlusion and It’s Relevance to Physical, Physiologic and Biological Laws

“With the advent of mandibular kinesiography (1974) and computerized mandibular scanning (1984), mandibular kinesiology has acquired a new dimension as a valuable sub science in oral physiology.91  Kinesiology is defined as “the science of human motion:. The ability to track and record mandibular movement is an indispensable modality for the diagnosis of musculoskeletal dysfunctions of the head and neck.  Disorders such a temporomandibular joint and myofascial pain dysfunction syndromes, muscle tension, bruxing, clenching, and instability of the occlusion all come under this classification. Today, no diagnosis of functional disorders should be considered adequate without kinesiometric analysis. This new dimension of treatment of the stomatognathic complex necessitates the use and understanding of a vocabulary that defines the quantifiable dimensions of neuromuscular movement.”

These are the words of Dr. Robert Jankelson, DDS.  A true living genius in the world of NM dentistry. I am inspired by the words he uses…the choice terms he arrives at to convey these profound concepts.  Like “kinesiometric analysis”, “the stomatognathic complex”, “new dimensions”…. As he brilliant stated…. This CMS or “mandibular kinesiology” is a valuable “sub science in oral physiology” necessitates the use and understanding of a vocabulary that defines the quantifiable dimensions of neuromuscular movement.”

LETS ALL TAKE TIME TO CONTEMPLATE what this all means and entails. Use this kind of vocabulary in your conversation with our colleagues and patients.

Telephone: (702) 271-2950


Leader in Gneuromuscular and Neuromuscular Dentistry