1) Body Posture Evaluation in Subjects with Internal Temperomandibular Joint Derangements. 2009. Munhoz et al. The Journal of Craniomandibular Practice, Volume 27, Number 4.
The purpose of this study was to determine if a relationship was present between global body posture and temperomandibular joint internal derangement (TMJ-id). Thirty subjects presenting with typical TMJ-id signs were compared to 20 healthy controls. Body posture was assessed by analysing muscle chains on several photographs. The results of the study showed a higher frequency of shoulder elevation (p=0.04) and of changes in the antero-internal hip chain (p=0.02) to the controls. No other differences were present. Further division into severity subgroups showed a trend towards subjects with more severe dysfunction with forward head and shoulder posture.
Clinical Implication: Postural control is an essential component of conservation of muscle energy and in preventing repetitive overuse injuries. The TMJ can be affected profoundly overtime by something as simple as posture. Hence, it implies a mode for prevention of degenerative TMJ changes. With the number of sedentary professions that often result in sub-optimal postures over time, is it possible to prevent many of the internal changes that we see clinically, prior to their occurrence? Hip strength may also be a modifiable factor in prevention that is quite simply to train with a structured program and maintenance schedule.
2) A Case of Facial Myofascial Pain Syndrome Presenting as Trigeminal Neuralgia. 2009. Zhoo Yoon et al. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. Volume 107.
This case study described the clinical presentation of an 83-year old female presenting clinically with a 10 year history of right facial pain. The article described a case of facial myofascial pain that presented with features consistent with trigeminal neuralgia (TN). Treatment of the myofascial elements of the patients’ pain, consisting of 8 trigger point injections, trigger point release and 7 infraorbital nerve blocks over a 4 week period was discussed. The combined treatment relieved pain to a 0-1/10, which was maintained at 2 year follow-up. Symptom presentation of TN may often involve electric shock-like pain along the ophthalmic, maxillary or mandibular nerves which typically occurs due to traumatic compression of the trigeminal nerve, neoplastic mechanisms, infection or vascular pathologies. Presence of myofascial pain, which may mimic or occur in conjunction with TN, often presents with palpable trigger points within the zygomaticus major or minor, orbicularis oculi, levator labii, lateral pterygoid muscles and tenderness of the temporalis tendon. These points may be latent (producing no referral or symptoms) or active trigger points (producing symptom report of facial, head or neck pain with or without headache).
Clinical Implication: While the differential diagnosis of TN must include glossopharyngeal neuralgia, post-herpetic neuralgia and atypical facial pain, a myofascial contribution is quite common in clinical practice. Physiotherapy, often including a combined approach with massage therapy, in additional studies has shown to be quite effective in treating myofascial pain. Acupuncture combined with local muscle retraining is also supported in the literature. As the TMJ is quite a unique joint in its functional make-up and neural innervations, a combined approach of physiotherapy with medical, pharmacological and dental intervention is often required for a successful outcome.
3) Effect of 2 jaw exercises on occlusal function in patients with obstructive sleep apnea during oral appliance therapy: A randomized controlled trial. 2009. Ueda et al. Am J Orthod Dentofacial Orthop. Volume 135.
This study compared the effects on objective occlusal function of 2 types of jaw exercises during oral appliance therapy in patients with obstructive sleep apnea (OSA). Sixteen subjects with snoring or OSA were included; 10 subjects completed the study. Patients were randomized into either a jig exercises or stretching group for a period of 1 month. After 1 month without exercise, they crossed over to the other exercise for 1 month. A pressure-sensitive sheet and an image scanner were used to evaluate occlusal contact area and bite force. Both exercises produced significant increases in occlusal contact area and bite force in the morning compared with the period of no exercise. At night, the molar region had significant improvements in occlusal contact area and bite force only in the stretching group. No significant differences were present between the two groups; however, there was a trend for improved molar region contact in the stretching group, while the jig exercise group showed more effective in the anterior region.
Clinical Implication: Jaw exercises may help to relieve masticatory muscle stiffness and accelerate the repositioning of the mandible to neutral. Occlusal functional changes may also be minimized or inhibited. Although the small sample size of the study and lack of long-term follow-up could be improved, it does provide support for a combined approach of exercise and oral appliance therapy in patients with OSA.
4) Influence of the temporomandibular joint on range of motion of the hip joint in patients with complex regional pain syndrome. 2009. Fischer et al. Journal of Manipulative Therapeutics. Volume 32, Number 5.
The study by Fischer’s group evaluated if patients with complex regional pain syndrome (CRPS) would have an increase in range of motion (ROM) after myofascial release, and a similar ROM decrease after jaw clenching. This was compared to healthy controls where the effects were assumed to be minimal or nonexistent. Twenty patients with CRPS were classified based on the research diagnostic criteria for CRPS, questionnaires, average pain intensity over a 4 week period and the temporomandibular index (TMI). Hip ROM was measured at baseline, after myofascial release of the TMJ and after jaw clenching for 90 seconds. Comparison of the CRPS and control groups were made using t tests. The results demonstrated a mean TMI score and mean pain score as being statistically significantly improved between the 2 groups (p<0.0005). Hip ROM in the CRPS group was also significantly improved between baseline and clenching and after the mobilizations (p<.0005). The results suggested that TMJ dysfunction can play an important role in the restriction of hip ROM experienced by patients with CRPS.
Clinical Implication: We know from the literature that TMJ dysfunction can affect nearby regions, such as the upper or mid cervical spine. Dysfunctions in these two regions are often cyclical and act to maintain each other once pain patterns are established. We also know from John et al., that in women, widespread pain is a risk factor for development of TMJ disorders. The reverse is also possible. Through ascending and descending pathways, oral motor activity can exert strong influence in distant parts of the body. An example of this can be found in research that has suggested a link between voluntary teeth clenching and in increase in the H-reflex in the soleus muscle, maintained through descending influence from the cerebral cortex. We also know that patients with CRPS often go on to develop signs and symptoms of TMJ disorders, as well as 88% presenting with a reduction in hip internal ROM. The technique applied to the TMJ in the current study was simple traction in an antero-caudal direction at the barrier of joint play for 90 seconds; an effective method of treatment for localized TMJ symptoms that physiotherapist employ routinely. Such a simple technique, applied in a clinical setting can also be instructed at home as part of a TMJ exercise program. The research is promising and this link is quite intriguing.
PLEASE VISIT THIS PAGE REGULARLY FOR UPDATED PHYSIOTHERAPY RESEARCH PERTAINING TO THE TMJ AND FACIAL PAIN
I welcome your comments on the material posted to this site. Please feel free to contact me at jtaddeo@fairwayphysio.ca . Jason Taddeo, M.Sc.(PT), H.B.K., CAFCI, RCAMPT
September / October 2009
A Systematic Review of the Effectiveness of Exercise, Manual Therapy, Electrotherapy, Relaxation Training, and Biofeedback in the Management of Temperomandibular Disorder. 2006. Medlicott et al. Physical Therapy. Volume 86 Number 7.
Main Recommendations:
(1) active exercises and manual mobilizations may be effective;
(2) postural training may be used in combination with other interventions, as independent effects of postural training are unknown;
(3) mid-laser therapy may be more effective than other electrotherapy modalities;
(4) programs involving relaxation techniques and biofeedback, electromyography training, and proprioceptive re-education may be more effective than placebo treatment or occlusal splints;
(5) combinations of active exercises, manual therapy, postural correction, and relaxation techniques may be effective.
Clenching and Grinding: Effect on Masseter and Sternocleidomastoid Electromyographic Activity in Health Subjects. 2009. Venegas, et al. The Journal of Craniomandibular Practice. Volume 27 Issue 3.
This study compares the effect of clenching and grinding on masseter and sternocleidomastoid electromyographic (EMG) activity during different jaw posture tasks in the sagittal plane. The study included 34 healthy subjects with natural dentition, Class I bilateral molar Angle relationship, and absence of posterior occlusal contacts during mandibular protrusion. An inclusion criterion was that subjects had to be free of signs and symptoms of any dysfunction of the masticatory system. Bipolar surface electrodes were located on the right masseter and sternocleidomastoid muscles. EMG activity was recorded while the subjects were in standing position, during the following jaw posture tasks: A. maximal clenching in the intercuspal position; B. grinding from intercuspal position to edge-to-edge protrusive contact position; C. maximal clenching in the edge-to-edge protrusive contact position; D. grinding from edge-to-edge protrusive contact position to intercuspal position; E. grinding from retrusive contact position to intercuspal position. EMG activities in tasks B, C, D, and E were significantly lower than in task A in both muscles (mixed model with unstructured covariance matrix). EMG activity among tasks B, C, D, and E did not show significant differences in both muscles, except between tasks D and E in the masseter muscle. A higher effect was observed on the masseter than on the sternocleidomastoid muscle to avoid excessive muscular activity during clenching and grinding. The EMG patterns observed could be of clinical importance in the presence of parafunctional habits, i.e., clenching and/or grinding. [This content has been reproduced based on the online content of Cranio – http://cranio.com]
Masseter Tenomyositis. 2009. DuPont, Jr., et al. The Journal of Craniomandibular Practice. Volume 27 Issue 3.
The masseter muscle is an integral part of the oral facial complex and one of the muscles of mastication. It functions with the other masticatory muscles in moving and posturing the mandible and in verbalizing, eating and swallowing. When a patient has temporomandibular dysfunction (TMD) or a myogenic disorder, the integrity of the masseter muscle can be compromised resulting in pain, malfunction, inflammation and/or swelling. A careful evaluation of the masseter muscles is necessary in facial pain patients since the pain can originate from a distant site and be referred to this area. One of the little known disorders involving the masseter and its tendinous origin is tenomyositis, in which an inflammation of the muscle and its tendon occurs. In this retrospective study, the charts of 114 consecutive patients (N=114) were evaluated to determine the prevalence of this disorder and the reported etiology. [This content has been reproduced based on the online content of Cranio – http://cranio.com]
Electromyographic Evaluation of Neuromuscular Coordination of Subject after Orthodontic Intervention. 2009. Botelho et al. The Journal of Craniomandibular Practice. Volume 27 Issue 3.
The aim of this work was to investigate the neuromuscular changes associated with the orthodontic post-treatment using surface electromyography. One hundred (100) young, healthy adults without signs and symptoms of temporomandibular dysfunction (TMD) were divided into two groups: 60 subjects who were undergoing orthodontic intervention (Ortho Group) and 40 subjects who had no orthodontic intervention (Control Group), aged 18-25 years. EMG activity of masseter and temporalis anterior muscle was recorded during two different tests: 1. maximum voluntary clench (MVC) with cotton rolls; and 2. MVC in intercuspal position. In all subjects, both tests were performed with symmetric muscular patterns (more than 85%) and with insignificant latero-deviating of the mandible (lower than 10%). There are no statistically significant differences between the subjects of both groups evaluated. Both groups showed medium index values calculated according to the normal standards established previously. [This content has been reproduced based on the online content of Cranio – http://cranio.com]