Electromyographic Evidence of Reduced Muscle Activity When ULF-TENS Is Applied to the V^th and VII^th Cranial Nerves

ABSTRACT

The object of this study was to determine if the resting muscle activity of TMD patients with measured hyperactivity (EMG_ave > 2.0 microvolts) could be reduced by the application of ULF-TENS (Ultra-Low-Frequency-Transcutaneous Electrical Neural Stimulation) [(BioTENS) BioResearch, Inc. Milwaukee, WI], Twenty-nine patients with resting muscle hyperactivity and ten without resting muscle hyperactivity were selected from a series of 124 consecutively diagnosed TMD patients. Electromyographic records were taken bilaterally (with the mandible at rest) from the superficial masseter, anterior temporalis, anterior digastric, and posterior temporalis muscles before and after the application of ULF-TENS. The EMG data were averaged. For the 85 muscles that were found initially to exceed the usual cutoff of 2.0 microvolts, means and standard deviations were calculated. The “before TENS” levels were: mean = 3.353 ± 1.44227 and the “after TENS” values were: mean = 1.844 ± 0.92421. Using a student t-test, we found the difference between the before and after levels significant (p <.0005). Additionally, means and standard deviations were calculated for each muscle (Ta, Mm, etc.) separately and also found to be significantly different (before Vs after TENS). In these “hyperactive” patients, the nonhyperactive muscles were also pooled, the means calculated before (mean = 1.21 ± 0.456) and after (mean = 1.00 ± 0.345) TENS and found to be significantly different (p < 0.01). For the ten patients exhibiting no muscle exceeding the 2.0 microvolt cutoff (mean = 1.08 ± 0.415), no significant change (in levels) was observed after ULF-TENS (mean = 0.96 ± 0.359; p > 0.88); however, when we calculated the “paired difference,” we found a significant reduction, albeit very slight, in these patients' muscles, too. We conclude that ULF-TENS has an activity-reducing effect on the resting EMG levels of both hyperactive and relaxed muscles. It also appears that while the > 2.0 microvolt cutoff is useful for identifying patients that are hyperactive at rest, it does not identify complete relaxation of masticatory muscles.

Additional information

Notes on contributors

Greg Kamyszek

Mr. Greg Kamyszek received his B.S. degree in clinical psychology and human services from the University of Wisconsin, Stevens Point. He is Vice President of Customer Services at BioResearch Associates, Inc. He is a member of the Academy of Oral Dynamics and the International Association for Dental Research. Mr. Kamyszek presented the abstract of this study at the 78th General Session of the International Association for Dental Research in Washington, DC April 5–8, 2000. He regularly provides in-service training to dental health care facilities in the proper use of computer-based diagnostic instrumentation.

Robert Ketcham

Dr. Robert Ketcham received his D.D.S. and M.S.D. degrees from Indiana University. He maintains a private practice in Fort Wayne, Indiana, limited to TMD diagnosis and treatment. He is certified by the Indiana State Board of Dental Examiners as a provider of continuing education programs. Dr. Ketcham maintains memberships in the American College of Prosthodontists, the American Equilibration Society, and the International College of Dentists. He has co-authored several research studies presented at previous meetings of the International Association for Dental Research and the American Academy of Orofacial Pain.

Ralph Garcia

Dr. Ralph Garcia, Jr. received his D.D.S. from Emory University and subsequently served in the Air Force as Chief of Prosthetics at Lockbourne AFB in Ohio. He maintains a private practice in Tampa, Florida, and is the dental consultant for temporomandibular imaging at the South Florida College of Medicine. He is a member of the American Equilibration Society, the American Academy of Craniofacial Pain, and the International College of Craniomandibular Orthopedics. Dr. Garcia lectures internationally and conducts in-house seminars on the diagnosis and treatment of temporomandibular disorders. He has authored a number of original scientific articles on the many facets of TMD diagnosis and treatment.

John Radke

Mr. John Radke received his M.B.A. from Keller Graduate School of Management (Chicago, Illinois). He is president of BioResearch Associates, Inc., where he has developed a number of diagnostic products since 1983. He is a member of the International Association for Dental Research, the International Neural Network Society, and an honorary member of the Italian Academy of Electromyography and Kinesiography. Mr. Radke lectures internationally on the scientific methods (Fourier series, wavelet transforms, artificial neural networks and genetic algorithms) that are used for the analysis of the following: 1. vibrations recorded from the temporomandibular joint; 2. electromyographic data from the muscles of mastication and 3. functional and parafunctional jaw movement data. During his career he has received a number of patents for his innovative instrument designs.