OBJECTIVE MEASURING TECHNOLOGIES: A Physiologic and Functional Bases to the Diagnosis and Treatment of TMD

Temporomandibular disorders (TMD) is defined as a group of clinical problems that involve the masticatory muscles, the tempormandibular joint (TMJ), and the associated structures.<1> The associated and supporting structures are the dentition and the neuromuscular system complex that are attached to the mastictory muscle system and the temporomandibular joint system.  TMD can coexist with other musculoskeletal disorders within the head and neck area. A composite of different entities that relate to each individual TMD patient’s pain and physical dysfunction can also lead to manifestation of psychological stress.  There are a number of varied signs and symptoms determined upon clinical examination that have been the subject of extensive research published in the medical and dental literature.<2>

There are some who skeptically believe and endorse a counter thought to the diagnosis and treatment of TMD.  In a recent papers (March 11, 2013, Journal of Canadian Dental Association (JCDA): “How Effective Is the Neuromuscular Occlusion Approach in diagnosing and treating TMD?”  based on the Rapid Response Report developed by the Canadian Agency for Drugs and Technologies in Health (CADTH): ” Neuromuscular Occlusion Concept-based Diagnosis and Treatment of Tempromandibular Joint Disorders: A Review of the Clinical Evidence stated on the JCDA  blog page (http://www.jcdablogs.ca/2013/03/11/tmd/) the following misleading statement in their KEY MESSAGE:

Diagnosing TMD: 

  • The use of electromyograms (EMG) is not supported by evidence.  (FALSE AND MISLEADING)
  • There is insufficient evidence to determine the diagnostic value of kinesiography.  (FALSE AND MISLEADING)

Treating TMD:

  • Electrical stimulation is not supported by evidence.  (FALSE AND MISLEADING)
  • The efficacy of occlusal splints is uncertain.  (FALSE AND MISLEADING)

The JCDA further stated in their “Findings” section the following:  “ Various studies related to the diagnostic values of the electromyography in TMD patients showed that the technology produced a wide range and inconsistent values of specificity and sensitivity that prevent its adoption as a diagnostic test for TMD. The EMG indices were not consistently different between TMD patients and the healthy controls. Furthermore, the EMG indices correlated poorly with the clinical signs and symptoms of TMD, such as pain and function.  Other studies on the electrical stimulation of muscular muscles showed that the use of contingent electrical stimulation was not different from the use of placebo in changing the clinical outcome or the electromyographic evaluation.”

Again, these published statements are misleading and very incomplete in their investigative research.  One has  to question exactly what was this report trying to convey?

In this age of the internet where the general public are now developing a much higher dental IQ, it is the responsibility of each individual and overseeing dental organization to be very prudent in their publication of findings.  Whether the JCDA blog intended it or not, people who read these messages would conclude that the neuromuscular approach is ineffective.  Today clinicians are seeing patients who are benefiting from the Neuromuscular  method.     There will always be studies that will favor or refute the neuromuscular methods.  The fact of the matter is that the causes of TMD are multi-factorial which is why there is no one mode of treatment that can claim 100% success.  Success of treatment is based on the knowledge and expertise of each operator rather than the instrumentation used.  Neuromuscular dentistry is conservative nature (reversible vs. irreversible procedures).  Isn’t it time that regulatory agencies as the Canadian Agency for Drugs and Technologies in Health (CADTH) should re-examine the pre-defined inclusion criteria used in this “Rapid Response Report), reconsider its position statements as well as the intent of the authors who wrote this report.

To read other dentist outrage comments see: http://www.jcdablogs.ca/2013/03/11/tmd/


“Publication bias remains an area of contention amongst those who assess the quality of systematic reviews within the dental community. It remains a research priority because it is unclear what the impact of publication bias is on making decisions in health care. We are aware of the 20 years of work that has gone in this area of research. This has given us some clear answers as to the effect publication bias may have on the overall results of estimating the impact of interventions.”<5>  A measurement tool for assessment of multiple systematic reviews (AMSTAR) was used as a tool for measuring the methodological quality of systematic reviews and content validity.  Authors of AMSTAR too recognize that “Additional studies are needed with a focus on the reproducibility and construct validity of AMSTAR, before strong recommendations can be made on its use.”<5>

In this 37 page document presented to the CADTH  it is evident that the drafters of this work clearly have done a lot of work, but the reviewers ‘ bias is quite evident. They have selected a group of references that lack many supportive studies. Two of the Cooper studies were included, but yet they rejected Cooper’s studies because it did not meet their selection criteria.  They have violated their own tenet of “clinical evidence”, considering the conclusions that were reached in the Key Findings (page 2) “The use of electrical stimulation for the treatment of TMD is not supported by the current evidence”.   They based their conclusions on two studies by Monaco, et. al. and Jadidi et. al.

With further more detailed analysis of what they are reporting, they violated their own tenet of “clinical evidence” and proper balance reporting by creatively and purposely eliminating what data and information they desire to report (cheering picking the literature) or construing as evidence to their summary findings based on their biased methods of ruling out what they feel is valid to convey their message –  swaying the reader to conclude… “The diagnostic accuracy values of EMG were reported in two studies; both studies reported a wide range and inconsistency values.”

This type of academic literature research does not meet the criteria of presenting a balanced perspective of all the evidence on electromyography (EMG) use in clinical dentistry.  Rather the researchers chose to bias their findings based conveniently on their own established terms of sensitivity and specificity.

In the Efficacy Studies section page 5,  the reporters did not properly acknowledge the conclusions of the Monaco et al. study accurately or completely. It actually states: “Significant differences were only observed in the TENS group for masticatory muscles of both sides; one-way analysis of variance revealed that sEMG values of masticatory muscles of both sides in he TENS group were significantly reduced.”…but rather the researchers prefer to report: “….The evaluation was based on EMG and kineseographic indices without any clinical outcomes.” (The researchers did not disclose the actual effects of this 60 min. TENS application on sEMG and kinesiographic activity in this TMD patient study.)

Erroneous reporting was also evident where the researchers site the Jadidi et al study on page 7 in the Efficacy Studies section, but did not disclose this study used an “electrical square wave pulse train (450 ms)” biofeedback stimulator type unit rather than a low frequency TENS which is indicated specifically for relaxing muscles. It is not surprising that muscle tension was not reduced/relaxed using that kind of biofeedback modality in that study, thus the researchers are again cheering picking their literature studies to convey a wrong message about EMG and TENS efficacy and or the researchers are not clearly distinguishing the differences between electrical square wave pulse biofeedback stimulators vs. ultra low frequency TENS.  They are not the same.  It’s like comparing apples to oranges…thus their reported conclusions and results of this study are in question as to it’s reliability, sensitivity and specificity of their conclusions.  This literature research study adds doubt and little confidence to the accuracy of this “Rapid Response Report”.

There are many TENS studies that they overlooked but the only study they produced that used a Myomonitor (Monaco’s study) indeed substantiates the efficacy of TENS in reducing muscle tension!!


1. What is the clinical evidence on the use of the neuromuscular occlusion (NMO) concept for diagnosis of temporomandibular joint (TMJ) disorders?

2. What is the clinical evidence of the effectiveness of occlusal adjustments, based on the neuromuscular occlusion concept, in treating TMJ disorders?

Clinical Evidence on the Use of Neuromuscular Occlusion for the Diagnosis and Treatment of TMD:

Scientific literature including the International Journal of Dental Research and the “Literature Review of Scientific Studies supports the Efficacy of Surface electromyography, Low Frequency TENS and Mandibular Tracking from Occlusion Evaluation and Aids in the Diagnosis and Treatment of TMD”  by Jankelson RR and Adib F (2009) published by Myotronics Noramed, Inc. has  presented sufficient data and science to confirm their clinical validity in dentistry.

  • Known research findings on the effect of TENS on the electromyography frequency raw data (Thomas NR (1990), “Pathphysiology of Head and Neck Musculoskeletal Disorders: The effect of fatigue and TENS on the EMG mean power frequency” in Frontiers of Physiology vol 7:162-170  has been supported by a grant from MRC Canada and has been confirmed by Eble et. al. at Frieberg University Germany.
  • The efficacy of electromyography in clinical dentistry has been clearly substantiated by numerous studies in the medical and dental literature.  (For more references to scientific studies, See “The Efficacy of Electromyography in Clinical Dentistry”).

Monaco, A, et.al., in their study using 60 minutes of TENS application on surface electomyography (sEMG) and jaw tracking (kineseographic activity) in TMD patients in remission and to assess the sEMG and kinesiographic effect of TENS in placebo and untreated groups reported, “Significant differences were only observed in the TENS group, for masticatory muscles of both sides; one-way analysis of variance revealed that sEMG values of masticatory muscles of both sides in the TENS group were significantly reduced, in comparison with placebo and control groups.”….”TENS could be effective to reduce the sEMG activity of masticatory muscles and to improve the interocclusal distance of TMD patients in remission; the placebo effect seems not present in the TENS application.”<4>

There is sufficient supportive evidence showing efficacy for the use of Low Frequency Transcutaneous Neural Stimulation (TENS), Electromyography (EMG), Jaw Tracking (Kineseography) and Electrosonography (ESG) in the Diagnosis and Treatment of TMD:

Some reviewers have reached invalid conclusions regarding the value of surface EMG in evaluating TMD patients because EMG as a stand alone modality can not make a diagnosis i.e. rule-in or rule-out TMD.  An EMG device does not make a diagnosis.  Along with history, visual examination and imaging, the EMG data provide more knowledge for the dentist in making his or her diagnosis or evaluating treatment progress of a given patient.  Despite the lack of the objectivity of these reviewers in their selection of 4 of the 6 studies they chose to investigated the EMG of masseter and temporalis muscles the studies concluded that “there was a statistically significant difference between TMD patients and a control group”  further reinforcing the value of surface EMG as an aid in the evaluation of TMD patients, for planning effective treatment and for evaluating patients’ response to treatment.  (This is what was not reported by these bias researchers.)

With regards to the clinical efficacy of TMD treatment based on the electrical stimulation of muscular muscles, these researchers have tried to limit their study down to one randomized-controlled trial and two non-randomized trial.   It is indeed very puzzling that with numerous studies of the efficacy of low frequency TENS that  have been published (Wessberg et al, Boschiero et al, Konchak & Thomas, Eble et al, Weggen et al, Cooper), they only decided to select only 2.  Regarding the Efficacy of TENS: The Reviewers exclude significant number of studies in support of the efficacy of TENS in treatment of TMD.  Of the two studies that they include, one was irrelevant and the second study by Monaco et al, a placebo-controlled study, strongly supported the efficacy of TENS in reducing muscle tension and increasing vertical interocclusal distance.  Therefore, the statements they try to promote and propogandize falsely reports that “The use of electrical stimulation for the treatment of TMD is not supported by the current evidence” is false and contrary to clinical evidence reported and documented in the Monaco et al’s study and many others.

Of the total of 596 articles that were identified by these reviewers, only one article was selected (Silva, et. al. ref. 28) page 5 of the CADTH report, to assess the efficacy of “occlusal splints prepared using the EMG values as a reference of ideal occlusion”.  Silva et al’s study had a control group of asymptomatic subjects and concluded that “the use of the splint promoted balance of the EMG activities during its use, relieving symptoms. EMG parameters identified neuromuscular imbalance, and allowed an objective analysis of different phases of TMD treatment, differentiating individuals with TMD from the asymptomatic subjects”.  Despite the authors findings and conclusions, the reviewers made this misleading statement in their report, stating,  “No conclusions can be made on the efficacy of the occlusal splint on the neuromuscular occlusion concept” presumably because this study that strongly supports the use of an EMG derived occlusal splint did not use another “therapeutic modality” to treat a controlled group of patients.



(Related to the reviewers’ statements in the Key Findings and the Conclusions Sections of the CADTH Report): The conclusions reached by these reviewers can not be supported by the clinical evidence presented in the studies they selected for review.

Related to the whole body of medical/dental research articles: The conclusion reached by a manyof reviewers, academics and clinicians indicates a substantial body of scientific evidence supports the efficacy and  use of electormyography, low frequency TENS, kineseographic (Jaw Tracking) and electrosonography for diagnosis of temporomandibular joint (TMJ) disorders.



1. de Felicio CmM, Ferreira CL, Medeiros AP, Rodrivues Da Silva MA, Tartaglia GM, Sforza C.: Electromyographic indices, orofacial myofunctional status and temporomandibular disorders severity: a correlation study. J Electromyogr Kineseol. 2012 Apr;22(2):266-72.

2. Cooper BC, Kleinberg I.: International College of Cranio-Mandibular Orthopedics (ICCMO).  Temporomandibular disorders: a position paper of the International College of Cranio-Mandibular Orthopedics (ICCMO).  Cranio. 2011 Jul;29(3):237-44.

3. Thomas NR:  ”Pathphysiology of Head and Neck Musculoskeletal Disorders: The effect of fatigue and TENS on the EMG mean power frequency” in Frontiers of Physiology. 1990 Vol 7:162-170.  (Norman Thomas, PHD; DDS:MB.BSC;FRCD; Certs Oral Path and Med; Med Ac(Alta) Professor Emeritus University of Alberta Canada).

4. Monaco, A, et.al.: Effects of transcutaneous electrical nervous stimulation on electromyographic and kinesiographic activity of patients with temporomandibular disorders: a placebo-controlled study”. J Electromyogr Kinesiol, 2012 Jun;22(3):463-8. DOI: 10.1016/j.jelekin.2011.12.008.Epub 2012 Jan 14.

5.Shea, BJ, et.al.:Development of AMSTAR: a measurement tool to assess the methodological quality of systematic reviews. BMC Med Res Methodol. 2007; 7: 10.Published online 2007 February 15. doi: 10.1186/1471-2288-7-10.

Discovering GNEUROMUSCULAR Dentistry and the latest in Dental Continuing Education

Neuromuscular Dentistry – Objective Measurements and Evaluation


A Discipline of Physiologic Dentistry

Clayton A. Chan, DDS, MICCMO
Master International College of Craniomandibular Orthopedics

For the past forty three years, dentistry has enjoyed an exciting evolution in the delivery of care. Technological advances have predominantly driven this evolution. Scientific advances have resulted in dental materials as technological break throughs using bio-instrumentation that have completely changed our perspectives on how dentist diagnose, manage and treat their cases. Technological advances have also allowed us to go beyond visualizing occlusal relationships solely from an anatomic perspective.

The early years from 1967 to 1977 gave insights and appreciation for the intellectual and courage of Dr. Bernard Jankelson (the Father of Neuromuscular Dentistry) single handedly challenged the dental occlusionist establishment with science and technology we now may take for granted and is available today.  Dr. Jankelson fight for new technology and new paradigmns to dental occlusal treatment brought to light the dogmas, scepticisms and epic confrontations from various levels of the profession.

After Dr. Jankelson’s death in 1987, battles erupted in the American Dental Association and U.S. Food and Drug Administration.  By 1986 the scientific foundation for neuromuscular concepts and techniques were firmly ground in scientific literature and the technology was recognized as safe and effective for the purposes intended by the American Dental Association Council on Scientific Affairs.  The clinical techniques which continue to be advocated by his son Drs. Robert Jankelson, James F. Garry and Clayton A. Chan and others (through 2005) have been found to be precise, predictable and successful inspite of some continued attacks from those who ignore the documented science.  Neuromuscular clinicians who have endorsed this philosophy, approach and use of technology today continue to be attacked by leaders whose status and livelihood depended upon the defense of the scientifically indefensible, by third party carriers intent on denial of payment, by IME’s whose livelihood depend on dential of patient claims, and by psycho-social academics whose research funding depended upon adherence to a particular TMD paradigmn.

Read more on other recent Neuromuscular Dentistry political battles against Anti Instrumentation from the TMJ Psychosocial Philosophy groups

  • Science is a hard taskmaster, and in the light of mounting evidence that suggestions of computerized electro-diagnostic instrumentation are for the most part ultimately confirmed by painstaking scientific inquiry, perhaps it is time to re-examine whether scientific standards of proof of causality – rather than waiting for the bodies to fall – ought not give way to more timely and predictable measuring methods that give way to more objective diagnostic treatment protocols that are physiologic, consistent and predictable.

The Neuromuscular Paradigm
New knowledge and understanding of the influences of occlusal proprioception on the human body requires intimate knowledge of the histological, anatomic and physiologic realm of the neuromuscular complex. The dentist should not only be the caretakers of the dentition, but of the health of all the structures innervated by and/or associated to the trigeminal nerve. Understanding the physiologic mechanisms of the stomatognathic system allows simplified clinical procedures that can be applied in all facets of dentistry including the TMD dentist, orthodontic dentist and restorative dentist to treat his/her patients with greater precision and predictability. Neuromuscular principles of occlusion are not new to the profession, but further builds on past gnathological concepts on which our present dental profession is based on. The use of scientific instrumentation has been used to objectively quantify and validate physiologic discoveries to occlusion. This new knowledge and training confirmed with advanced technology allows the restoration of pathologic dentitions to stable healthy dentition previously unattainable for function, self preservation and aesthetics.

Our profession is now realizing the significance and importance of objectivity, especially when transitioning from academic knowledge to clinical treatment for our patients when: 1) an optimal bite is needed to begin a diagnosis for eventual treatment, 2) the importance of bite management during the phase I stabilization stage and finalizing the orthodontic and/or restorative phase II stage, and 3) finishing the bite to meet the physiologic parameters of stability and dental health.

For More Information See: Dental Continuing Education and Post Graduate  OC Dental Training

Today’s dental practitioners are recognizing the necessity to incorporate the latest biomedical technology into their contemporary dental practice. As dental science has evolved and new discoveries are being made through the aid of computer technologies greater responsibilities, capabilities and opportunities for the dental profession are being realized.

Physical, physiologic and biologic laws that govern articular and neuromuscular function at all structural levels of the human body apply to the masticatory apparatus. Generic biologic and physiologic principles that apply to all articular, muscular, neural and central nervous system organs are better realized and understood through the use of computerized Myotronic instrumentation that enhances the clinicians perspective of what is truly physiologic occlusion. Clinicians are recognizing the potential and effectiveness of applying the above mentioned neuromuscular principles to TMD, orthodontic and restorative dentistry. Myotronic instrumentation is able to deliver the reality of these profound NM concepts especially in the clinical setting. These concepts are unfortunately missed by many practitioners.

Five basic principles of occlusion that the physiologically minded clinician realizes when desiring optimal masticatory stability:

1. Acknowledges the multifaceted Musculoskeletal Occlusal Signs and Symptoms.
2. Identifies an optimal starting point for diagnosis and treatment “PHYSIOLOGIC REST” (Homeostasis) – without manual intervention.
3. Recognizes a physiologic mandibular opening and closing NM TRAJECTORY along an isotonic path for STABILITY at a terminal contact position.
4. MICRO-OCCLUSION- Eliminates the afferent and efferent noxious proprioceptive stimuli of occlusion during mandibular closure with FREEDOM OF ENTRY and EXIT.
5. Can accurately OBJECTIVELY MEASURE and RECORD muscle and postural responses of the mandible in establishing an occlusion before, mid and after treatment.

Many do not see the power of micro-occlusion, the importance of finding an optimal NM trajectory, starting from physiologic rest, the importance of removing mandibular torque, the importance of proprioception as it relates to the trigeminal system. These are the ingredients for an “optimal bite” many treating clinicians have been searching for to bring long term stability and success in their dentistry. Many have either over look these principles or gave up too quickly to relinquish their role of being a treating “dentist”, to other adjunctive modalities, because they did not see the connection of these points to their clinical problems. In short they got distracted from perfecting their main role of what they were licensed to do, being a dentist dealing with all the issues relating to the trigeminal nerve and THE BITE (Occlusion).

Thousands of clinicians all around the world have found that by applying these profound neuromuscular principles first that they are able to effectively get the results of some of the most challenging TMD, orthodontic and restorative patients who present with numerous musculoskeletal occlusal signs and symptoms, involving cranio-mandibular, neurovasomuscular/cervical/occlusal dysfunction.

For more information click: Finding a Qualified Neuromuscular Dentist

© 2009 Clayton A. Chan, DDS. All Rights Reserved.

The Leader in Neuromuscular and Gneuromuscular Dentistry


Clayton A. Chan, DDS, MICCMO
Founder and Director of Occlusion Connections

The following 13 points must be considered in understanding what “Neuromuscular Dentistry” is REALLY ABOUT. These points have been adapted from the writings of Dr. Robert Jankelson who has pioneered the clinical use of computerized bio-instrumentation along with his father Dr. Bernard Jankelson (the Father of Neuromuscular Dentistry).

  1. Physical, physiologic and biological laws that govern articular and neuromuscular function at all structural levels of the human body apply to the masticatory apparatus. A rigid mechanistic concept of masticatory function is not consistent with generic physiologic knowledge.
  2. The TMJ and intercuspal masticatory articulations are a continuum of the entire body posture articulation. Anatomic and/or physiologic changes at any postural level require compensatory neuromuscular accommodation.
  3. Clinical dysfunction and symptoms occur when the need for structural and physiologic accommodation exceeds the ability of the organ system to accommodate.
  4. Compression of anatomic structures is a generic medical model of pathophysiology, pain and dysfunction. Decompression of impinged anatomic structures is the medical therapeutic model.
  5. General laws of homeostasis support the desirability of analysis of maxillo-mandibular posture from optimal muscle relaxation. Relaxation is good in the postural state. Muscle tension is bad in the postural state.
  6. Good laws of homeostasis and entropy support physiologic closure along an isotonic path of closure to terminal intercuspation.
  7. Relaxation of masticatory muscles prior to diagnosis and therapeutic procedures is a fundamental neuromuscular paradigm.
  8. Ultra Low Frequency TENS (Myomonitor) is a well established and scientifically documented adjunct to facilitate masticatory muscle relaxation.
  9. Objectively measuring occlusal function/dysfunction is consistent with scientific methodology. If the following three questions are answered affirmatively the measurement devices have scientific and clinical validity.
    • 1) Can you measure a given physiologic function?
    • 2) Are you measuring that physiologic parameter accurately?
    • 3) Does that information add to the diagnostic information to assist diagnosis and treatment?
  10. Electromyography (EMG) is a safe and efficacious technique to monitor muscle at rest and in function.
  11. The medical and dental literature supports lowering EMG postural activities as objective data of improved muscle relaxation state which is a universal therapeutic medical objective.
  12. Increased isometric force in the intercuspal position as a desirable objective is consistent with all generic physiologic and medical models of kinesthesia.
  13. Mandibular malposition and occlusal dysfunction can initiate or contribute to temporomandibular disorders (TMD). TMD is a multi etiologic musculoskeletal dysfunction having common pathologic characteristic of all musculoskeletal disease.

Appreciation is extended to all treating clinician’s who have realized the realities of the importance of a thorough diagnosis and understanding of this complex system in order to bring treatment to a finalize stage of postural/cervical/occlusal stability, muscular balance, dental aesthetics for the patient seeking comfort and satisfaction.

Note: It is with distinct honor and privilege that I was a student of Dr. Robert Jankelson, forever my mentor and world class teacher.  I am forever grateful and appreciative of his relentless passion to share and communicate these concepts that have many dentist’s lives as well as my professional career.  (He often told me to be errudite and be humble.”)

For More Information See: Dental Continuing Education and Post Graduate  OC Dental Training

© 2009 Clayton A. Chan, DDS. All Rights Reserved.

The Leader in Neuromuscular and Gneuromuscular Dentistry