Temporomandibular Disorders

Number: 0028

Policy

Notes: Some Aetna HMO plans exclude coverage for treatment of temporomandibular disorders (TMD) and temporomandibular joint (TMJ) dysfunction, and may also exclude coverage for other services described in this bulletin (e.g., non-surgical management) The plan determines the scope of coverage.  Please check benefit plan descriptions for details.

For plans that cover treatment of TMD and TMJ dysfunction, requests for TMJ surgery require review by Aetna's Oral and Maxillofacial Surgery patient management unit.  Reviews must include submission of a problem-specific history (i.e., Aetna Temporomandibular Disorder Questionnaire) and physical examination, TMJ radiographs/diagnostic imaging reports, patient records reflecting a complete history of 3 to 6 months of non-surgical management (describing the nature of the non-surgical treatment, the results, and the specific findings associated with that treatment), and the proposed treatment plan.  The provider will be notified of the coverage decision after review of all pertinent data.

1. Diagnostic Testing

   Aetna considers the following medically necessary for diagnostic testing for TMJ/TMD using the following modalities:

1. Examination including a history, physical examination, muscle testing, range of motion measurements and psychological evaluation as necessary; and
2. Diagnostic X-rays - a single panoramic X-ray of the jaws is considered medically necessary for the initial evaluation of TMJ disorders. The current scientific literature does not show that additional x-rays will result in better, reproducible outcomes during the initial screening or when fabricating of a TMJD oral splint. Additional X-rays are considered medically necessary if surgery is contemplated; and
3. Computed tomography (CT) or magnetic resonance imaging (MRI) only when used in conjunction with anticipated surgical management.

2. Non-Surgical Management

   Comprehensive non-surgical management of TMJ/TMD includes all of the following, unless contraindicated:

   1. Reversible Intra-Oral Appliances:

      (i.e., removable occlusal orthopedic appliances-orthotics, stabilization appliances, occlusal splints, bite appliances/planes/splints, mandibular occlusal repositioning appliances [MORAs])

      Reversible intra-oral appliances may be considered medically necessary in selected cases only when there is evidence of clinically significant masticatory impairment with documented pain and/or loss of function.  Prolonged (greater than 6 months) application of TMD/J intra-oral appliances is not considered medically necessary unless, upon individual case review, documentation is provided that supports prolonged intra-oral appliance use.  Note: Appliances for bruxism are typically excluded under Aetna medical plans (please check benefit plan descriptions), but may be covered under dental plans.  Only 1 oral splint or appliance is considered medically necessary for TMD/TMJ therapy. 

      For plans that cover intra-oral appliances, adjustments of intra-oral appliances performed within 6 months of initial appliance therapy are considered medically necessary; while adjustments performed after 6 months are subject to review to determine necessity and appropriateness.  More than 4 adjustments or adjustments that are done more than 1 year after placement of the initial appliance are subject to review.  Note: Replacement of a lost, missing or stolen intra-oral appliance is not covered; while replacement (for other reasons) or repair is subject to review to determine necessity and appropriateness.
      
      Note:  Intra-oral appliances for the treatment of headaches or trigeminal neuralgia are considered experimental and investigational, as there is insufficient data on the effectiveness of this therapy.  See CPB 0688 - Intra-oral Appliances for Headaches and Trigeminal Neuralgia.

   2. Physical Therapy:

      Aetna considers physical therapy to be a medically necessary conservative method of TMD/TMJ treatment.  Therapy may include repetitive active or passive jaw exercises, thermal modalities (e.g., hot or cold packs), manipulation, vapor coolant spray-and-stretch technique, and electro-galvanic stimulation.  See CPB 0325 - Physical Therapy for medical necessity criteria and documentation requirements for physical therapy. For manipulation under anesthesia for TMD/TMJ, see CPB 0204 - Manipulation Under General Anesthesia.

   3. Pharmacological Management:

      Non-opiate analgesics and non-steroidal anti-inflammatory drugs (NSAIDs) are considered medically necessary for mild-to-moderate inflammatory conditions and pain.  Low-dosage tricyclic antidepressants (e.g., amitriptyline) are considered medically necessary for treatment of chronic pain, sleep disturbance and nocturnal bruxism.  Adjuvant pharmacologic therapies, including anticonvulsants, membrane stabilizers, and sympatholytic agents, are considered medically necessary for unremitting TMJ pain.  Opiate analgesics, corticosteroids, anxiolytics, and muscle relaxants are considered medically necessary in refractory pain.

   4. Relaxation Therapy and Cognitive Behavioral Therapy (CBT):

      Aetna considers relaxation therapy, electromyographic biofeedback and cognitive behavioral therapy medically necessary for treatment of TMJ/TMD.

      Relaxation therapy, electromyographic biofeedback, and cognitive behavioral therapy are considered medically necessary in chronic headaches and insomnia, which are frequently associated with TMD/TMJ conditions.  The above therapies may be considered medically necessary in treating these conditions as well.  Treatment in multi-disciplinary pain centers may be considered medically necessary in those few individuals who have been unresponsive to less comprehensive interventions. See CPB 0237 - Chronic Pain Programs.

   5. Acupuncture and Trigger Point Injections:

      (Note: some plans limit coverage of acupuncture only when used in lieu of surgical anesthesia.  Please check plan benefit descriptions for details. See CPB 0135 - Acupuncture).  Aetna considers acupuncture and trigger point injections medically necessary for persons with temporomandibular pain.  For acute pain, generally 2 visits per week for 2 weeks are considered medically necessary.  Additional treatment is considered medically necessary when pain persists and further improvement is expected.

   6. Manipulation for reduction of fracture or dislocation of the TMJ

      is considered medically necessary. 

3. Surgical Procedures:

   Surgical procedures include therapeutic arthroscopy, arthrocentesis, condylotomy/eminectomy, modified condylotomy, arthroplasty, and joint reconstruction using autogenous or alloplastic materials. In general, the least invasive appropriate surgical treatments should be attempted prior to progression to more complicated surgeries. Note: All TMJ surgical precertification requests or claims are reviewed by Aetna's Oral and Maxillofacial Surgery (OMS) Patient Management Unit.
   
   TMJ surgery may be considered medically necessary in cases where there is conclusive evidence that severe pain or functional disability is produced by an intra-capsular condition, confirmed by magnetic resonance imaging (MRI), computed tomography or other imaging, that has not responded to nonsurgical management, and surgery is considered to be the only remaining option. Nonsurgical management include three or more months of the following, where appropriate: professional physical therapy, pharmacological therapy, behavioral therapy (such as cognitive behavioral therapy or relaxation therapy), manipulation (for reduction of dislocation or fracture of the TMJ) and reversible intra-oral appliances (unless the member is unable to open mouth wide enough).  In certain cases (e.g., bony ankylosis and failed TMJ total joint prosthetic implants) that require immediate surgical intervention, surgery may be considered medically necessary without prior non-surgical management.  Note: All requests for surgery must include documentation that all medically appropriate non-surgical therapies noted above have been exhausted.  Patients with chronic head and neck pain may be candidates for chronic pain assessment. 

   1. Arthrocentesis with insufflation, lysis, and lavage is considered medically necessary when imaging and clinical examination reveal anchored disc phenomenon, anterior disc displacement without reduction and without effusion, osteoarthritis without fibrosis or loose bone particles, open lock, or hemarthrosis. Note: For purposes of this policy, arthrocentesis for TMJ internal derangement is defined as the insertion of two separate single- needle portals or a single double- needle portal for input and output of fluids.  The process includes insufflation of the joint space, lavage, manipulation of the mandible for the purpose of lysis of adhesions, and the elective infusion of steroids.
   2. Therapeutic arthroscopy is considered medically necessary when MRI or other imaging confirms the presence of adhesions, fibrosis, degenerative joint disease, or internal derangement of the disc that requires internal modification.
   3. Open surgical procedures including, but not limited to meniscus or disc repositioning or plication, disc repair, and disc removal with or without replacement are considered medically necessary when TMJ dysfunction is the result of congenital anomalies, trauma, or disease in patients who have failed nonsurgical management.
   4. Arthroplasty or arthrotomy includes: a) disk repair procedures; b) diskectomy with or without replacement; and c) articular surface recontouring (condylectomy and eminectomy or eminoplasty). Arthroplasty or arthrotomy is considered medically necessary when MRI or other imaging confirms the presence of any of the following: 
       
      1. Osteoarthritis or osteoarthrosis; or
      2. Severe disc displacement associated with degenerative changes or perforation; or
      3. Scarring that is severe and often the result of old injury or prior procedure

   5. Aetna considers joint replacement with an FDA-approved prosthesis (including the TMJ Concepts prosthesis, the Christensen TMJ Fossa-Eminence Prosthesis System (partial TMJ prosthesis), the Christensen TMJ Fossa-Eminence/Condylar Prosthesis System (Christensen total joint prosthesis), or the W. Lorenz TMJ prosthesis) medically necessary when used as a “salvage device” for treatment of end-stage TMJ disease, when conservative management and other surgical treatment has been unsuccessful, and MRI or other imaging documents one or more of the following:

      1. Temporal bone that no longer provides a smooth articular fossa; or
      2. Damaged condyles that are no longer ball-shaped; or
      3. Persistent, stable inflammatory arthritis that is not responsive to other modalities of treatment; or
      4. Recurrent fibrous or bony ankylosis that is not responsive to other modalities of treatment; or
      5. Loss of mandibular condylar height and/or occlusal relationship due to trauma, resorption, pathological lesion or congenital anomaly; or
      6. Failed autologous bone graft or alloplastic reconstruction effort.

   6. Autogenous grafts (e.g., costochondral, cartilage, dermal, fat, fascial and other autogenous graft materials) may be considered medically necessary upon individual case review.  Autologous costochondral grafts are considered medically necessary when criteria for joint replacement ( II.D.) are met or when there is congenital absence or deformity of the joint or for surgical reconstruction post head and neck tumor resection.   

4. Aetna considers the following experimental and investigational for diagnosis and treatment of TMJ disorders:

   1. Diagnostic procedures

      1. Cephalometric or lateral skull x-rays 
      2. Computerized mandibular scan/kinesiography/electrogathograph/jaw tracking
      3. Diagnostic study models
      4. Electromyography (EMG), surface EMG (see CPB 0112 - Surface Scanning and Macro Electromyography)
      5. Electronic registration (Myomonitor)
      6. Genetic testing
      7. Joint vibration analysis
      8. Measurements of circulating omentin-1 levels
      9. Muscle testing/range of motion measurements (incidental to examination)
      10. Neuromuscular junction testing
      11. Salivary stress biomarkers (e.g., alpha-amylase and cortisol levels)
      12. Somatosensory testing
      13. Sonogram (ultrasonic Doppler auscultation)
      14. Standard dental radiographic procedures
      15. Thermography (see CPB 0029 - Thermography)

   2. Non-surgical treatments

      1. Bio-oxidative ozone therapy
      2. Botulinum toxin (type A or type B) (however, botulinum toxin type A is considered medically necessary for jaw-closing oromandibular dystonia -- see CPB 0113 - Botulinum Toxin)
      3. Continuous passive motion (see CPB 0010 - Continuous Passive Motion (CPM) Machines)
      4. Cranial (craniosacral) manipulation (see CPB 0388 - Complementary and Alternative Medicine)
      5. Dental restorations/prostheses (see CPB 0082 - Dental Services and Oral and Maxillofacial Surgery: Coverage Under Medical Plans)
      6. Diathermy, infrared, and ultrasound treatments
      7. Dry needling
      8. Hydrotherapy (immersion therapy, whirlpool baths)
      9. Hypnosis/relaxation therapy
      10. Injection of plasma rich in growth factors
      11. Iontophoresis (see CPB 0229 - Iontophoresis)
      12. Intra-articular injection of hyaluronic acid (viscosupplementation)
      13. Intra-articular injection of platelet-rich plasma
      14. Intra-articular injections of rituximab
      15. Intraoral appliances for headache or trigeminal neuralgia (see CPB 0688 - Intra-oral Appliances for Headache and Trigeminal Neuralgia)
      16. Irreversible occlusion therapy aimed at modification of the occlusion itself through alteration of the tooth structure or jaw position
      17. Ketamine (local/intra-articular administration)
      18. Magnetic neurostimulator
      19. Manual therapy
      20. MIRO therapy
      21. Myofunctional therapy
      22. Myomonitor treatment (J-4, BNS-40, Bio-TENS)
      23. Neuromuscular re-education
      24. Orthodontic/bite adjustment services and orthodontic fixed appliances (see CPB 0095 - Orthognathic Surgery; and CPB 0082 - Dental Services and Oral and Maxillofacial Surgery: Coverage Under Medical Plans)
      25. Permanent mandibular repositioning (e.g., equilibration, orthodontics)
      26. Phototherapy (e.g., low-level (cold) laser therapy (LLLT) and light-emitting diode (LED) therapy) see CPB 0363 - Cold Laser and High-Power Laser Therapies)
      27. Prophylactic management of TMJ disorder, including occlusal adjustment
      28. Radiofrequency generator thermolysis (see also CPB 0400 - Ernest or Eagle's Syndrome (Stylomandibular Ligament Pain): Treatment with Radiofrequency Thermoneurolysis)
      29. Stem cell therapy
      30. Therabite Jaw Motion Rehabilitation System (see CPB 0412 - Therabite Jaw Motion Rehabilitation System)
      31. Transcranial direct current stimulation
      32. Transcutaneous electrical nerve stimulation (TENS) (see CPB 0011 - Electrical Stimulation for Pain)

   3. Surgical treatments

      1. Orthognathic surgery (see CPB 0095 - Orthognathic Surgery)
      2. Permanent mandibular repositioning (e.g., full-mouth reconstruction)
      3. Treatment of alveolar cavitational osteopathosis (see CPB 0642 - Neuralgia Inducing Cavitational Osteonecrosis (NICO) and Ultrasonograph Bone Densitometer to Detect NICO)

Background

Although the precise etiology of temporomandibular joint (TMJ) syndrome and temporomandibular joint disorder (TMD) has not yet been identified, these conditions are believed to be the result of either "macro" or "micro" trauma affecting the joint and/or the associated facial musculature.  Macro-trauma is usually historically obvious (e.g., acute joint overload), and there is generally a documented history of direct trauma to the TMJ.  Micro-trauma is a chronic and insidious process, multi-factorial in presentation, and commonly associated with para-functional habits, stress and anxiety, sleep disorders, dysfunctional occlusion, and various myofascial conditions (e.g., fibromyalgia).

The etiology of temporomandibular disorders are intracapsular or extracapsular.  Intracapsular abnormalities consist of internal derangements, including anterior disc displacement with or without reduction, disc perforation or fragmentation leading to degenerative joint disease, rheumatoid arthritis, synovitis, and neoplasia.  Extracapsular abnormalities consist of myalgia or myospasm which may be related to trauma or parafunctional habits such as bruxism, tooth pain, or postural abnormalities.  

The diagnosis of TMD is largely based upon the symptoms of pain and signs of TMD (e.g., joint sounds, variations from ideal disc position, clicking).  These signs may also be found in large segments of the general population without evidence of impairment or dysfunction.  According to available literature, specialized radiological studies (e.g., cephalometric x-rays, tomograms, submental vertex radiographs) are not medically necessary in evaluating persons with TMD unless surgery is being considered.

The extent of internal derangements is often determined by magnetic resonance imaging (MRI).  MRI is a useful for assessing disc morphology, disc fragmentation, and the disc-condylar relationship, especially where the patient is in a closed lock with a limited oral opening.  Limchaichana et al (2006) assessed the evidence for the effectiveness of MRI in the diagnosis of disk position and configuration, disk perforation, joint effusion, and osseous and bone marrow changes in the TMJ.  Two reviewers evaluated the level of evidence of relevant publications as high, moderate, or low.  Based on this, the evidence grade for diagnostic efficacy was rated as strong, moderately strong, limited, or insufficient.  The literature search yielded 494 titles, of which 22 were relevant.  No publication had a high level of evidence, and 12 had moderate and 10 low levels of evidence.  The evidence grade for diagnostic efficacy expressed as sensitivity, specificity, and predictive values was insufficient.  The authors concluded that evidence for the effectiveness of MRI is insufficient; and it emphasizes the need for high-quality studies on the diagnostic efficacy of MRI, incorporating accepted methodological criteria.

Therapy of TMD varies considerably according to the particular training, discipline and experience of the clinician.  This variation in clinical practice is due, in part, to a paucity of evidence-based outcome research and lack of consensus on the appropriate management of TMD.  Scientifically valid clinical trials are lacking for the vast majority of therapies that are currently employed.  There are also no objective, generally accepted, diagnostic standards to correctly identify when a TMD is present.

The appropriate diagnosis and treatment of TMD is complicated by a high incidence of TMD/TMJ signs and symptoms that are associated with systemic disorders.  These usually represent local or regional manifestations of chronic, global, musculoskeletal pain conditions, such as fibromyalgia, systemic myofascial pain and chronic fatigue syndrome.  While an association with headaches has been identified, a causal relationship between TMD/TMJ and headaches has not been established.  These conditions occur coincidentally and may be produced by etiologic factors that are common to both.

The National Institutes of Health emphasizes the importance of 2 key words in therapy: CONSERVATIVE and REVERSIBLE.  A growing body of literature supports non-surgical intervention for this condition.  Similar to other musculoskeletal/joint conditions, treatment is directed towards unloading the affected structures and managing the attendant discomfort.  Non-surgical therapy customarily includes occlusal appliance therapy, physical therapy, medical management, and relaxation/cognitive-behavioral therapy.  Prudence usually dictates that non-surgical therapy first be exhausted prior to any invasive therapies.  Patients with a long history of head and neck pain may be candidates for a chronic pain assessment.

The American Academy of Oral and Maxillofacial Surgeons Parameters of Care (2012) states: "Surgical intervention for internal derangement is indicated only when nonsurgical therapy has been ineffective and pain and/or dysfunction are moderate to severe.  Surgery is not indicated for asymptomatic or minimally symptomatic patients. Surgery also is not indicated for preventive reasons in patients without pain and with satisfactory function.  Pretreatment therapeutic goals are determined individually for each patient."

Appliance (splint) therapy has been shown to be beneficial for TMD.  These devices represent the most common and effective TMD/TMJ therapy that is routinely provided by dentists, even though the physiologic mechanism of the treatment response is not completely understood.  Splint design and usage are different depending upon whether the etiology is intracapsular or extracapsular.  For extracapsular problems, a night guard or bite plain appliance worn at night may help.  For intracapsular problems, the appliance needs to be worn through the entire day and night, except at meal times for a trial period of at least 2 to 3 months.  Appliance therapy would not be indicated for patients who are unable to open their mouth wide enough to obtain the impressions of dental arches that are necessary for making a dental model for a custom made appliance.

Physical therapy is an established conservative method of TMD/TMJ treatment.  As is the case with physical therapy for most other medical conditions, scientific evidence of therapeutic benefit from physical therapy in TMJ/TMD is limited.  Therapy may include repetitive active or passive jaw exercises, thermal modalities, manipulation, vapor coolant spray-and-stretch technique, and electro-galvanic stimulation.

Initial medical management of TMD/TMJ conditions may include pharmaceutical therapy, similar to other acute and chronic orthopedic and musculoskeletal conditions.  Non-opiate analgesics and non-steroidal anti-inflammatory drugs (NSAIDs) have been shown to be effective for mild-to-moderate inflammatory conditions and pain.  Low-dosage tricyclic anti-depressants (e.g., amitriptyline) are have been used successfully in the treatment of chronic pain, sleep disturbance and nocturnal bruxism.  Adjuvant pharmacologic therapies, including anticonvulsants, membrane stabilizers, and sympatholytic agents, may be useful for unremitting TMJ pain.  Opiate analgesics, corticosteroids, anxiolytics, and muscle relaxants are also used in refractory pain.

There is strong evidence of effectiveness for the relaxation class of techniques in reducing chronic pain associated with a variety of medical conditions.  See CPB 132 - Biofeedback.  The effectiveness of electromyography (EMG) biofeedback in the treatment of TMD has been evaluated in a meta-analysis of 13 studies.  Approximately 70 % of patients required no further treatment, were symptom free, or were substantially improved following EMG biofeedback therapy, compared with approximately 35 % of patients who received placebo treatments.  A synergistic response has been demonstrated when intra-oral appliance therapy is combined with biofeedback and stress management.  These results demonstrate the importance of using both dental and psychological treatments for successful intervention.  Cognitive-behavioral therapy (CBT) also has been demonstrated to improve long-term outcomes for TMD patients, as has been the case with other chronic pain disorders.  Behavior modification interventions and relaxation techniques are frequently included as a behavioral component of CBT.

Acupuncture and trigger-point injections may be used for TMD pain.  A systematic review found substantial evidence of the effectiveness of acupuncture for treatment of TMD pain.  While relatively fewer controlled studies on trigger-point injection have been conducted, trigger-point injection and dry needling of trigger points have become widely accepted.  While dry needling and trigger point injections of anesthetic appear to be equally effective, post-injection soreness from dry needling has been found to be more intense and of longer duration than experienced by patients injected with local anesthetic.

In cases involving chronic intractable pain and/or prior (including multiple) TMJ surgical procedures, caution is recommended due to the significant morbidity that may be experienced with TMJ surgical interventions.  The long-term prognosis of this therapy for intractable pain may be unfavorable, due to the neurophysiology of chronic pain disorders.  There is also evidence that the prognosis for success decreases with each additional (repeat) TMJ surgical intervention.  In such cases, the literature indicates that the most promising treatment may be admission into a multidisciplinary chronic pain treatment program.

In a review on TMD, Laudenbach and Stoopler (2003) noted that when patients do not respond to non-invasive TMD therapy, surgical procedures are considered.  Initial closed-approach, surgical options include arthrocentesis and arthroscopy of the TMJs.  These are the simplest and least invasive of all the surgical techniques.  More advanced, open-approach TMJ surgeries include disk re-positioning, diskectomy, and modified condylotomy.  Indeed, guidelines for the diagnosis and management of disorders involving the TMJ and related musculoskeletal structures that are approved by the American Society of Temporomandibular Joint Surgeons (2001) listed condylotomy (including modified condylotomy) as one of the surgical options.

In a prospective, controlled study, Hall et al (2005) compared the outcomes of 4 operations (arthroscopy, condylotomy, discectomy, and disc repositioning) used for the treatment of painful TMJ with an internal derangement.  Studies were conducted at 3 sites, and all sites used the same inclusion and exclusion criteria.  Trained, independent examiners assessed pain, diet, and range of motion before operation and 1 month and 1 year after operation.  There were statistically significant reductions in the amount of pain (p < 0.001) and daily time in pain (p < 0.001) that were similar for all 4 operations 1 month and 1 year after the procedures.  The degrees of change after each of the 4 procedures were not statistically different from each other (amount: p = 0.453 and time: p = 0.416).  Ability to chew, as measured by diet visual analog scale, was substantially improved 1 year after operation (p < 0 .001).  The degrees of change for diet at 1 year also were not different from each other (p = 0.314).  There were, however, statistically significant differences (p < 0.05) in range of motion that varied with procedure.  The authors concluded that all 4 operations were followed by marked improvements in pain and diet.  The amounts of improvement varied slightly by operation, but these differences were not statistically significant.  There were small but statistically significant differences between procedures for range of motion.

McKenna (2006) stated that the therapeutic objective of modified condylotomy is to increase joint space, providing immediate joint load reduction and reducing if not abolishing condylar interference.  The technical aspects of modified condylotomy are simple and familiar to surgeons comfortable with intraoral vertical ramus osteotomy.  Satisfactory pain relief following modified condylotomy for non-reducing disc displacement (NRDD) demonstrate that disc reduction is not a pre-requisite.  However, when disc reduction is possible, as it often is in reducing disc displacement joints or joints that have recently progressed to NRDD, the odds of pain relief, especially moderate to severe pain, are improved and lower the risk for re-operation.  Furthermore, modified condylotomy seems to favorably change the natural course of internal derangement/osteoarthrosis.

A partial TMJ prosthesis consists of a meniscectomy and placement of a metallic glenoid fossa metal prosthesis (Christensen fossa-eminence prosthesis, TMJ, Inc., Golden, CO) in place of the meniscus, such that a natural condyle articulates with a metal fossa prosthesis.  The U.S. Food and Drug Administration (FDA) Dental Products Advisory Panel reviewed clinical studies of the Christensen fossa prosthesis, and advised the FDA to approve the total prosthesis, but to not approve the partial joint prosthesis because of a lack of clinical data on its safety and effectiveness.  The information originally submitted to the FDA on the safety and effectiveness of the partial TMJ prosthesis was limited and had not been published in a peer-reviewed journal.  In an editorial, Laskin (2001), former editor-in-chief of the Journal of Oral and Maxillofacial Surgery, the official journal of the American Association of Oral and Maxillofacial Surgeons, commented on the data on the partial TMJ prosthesis presented to the FDA Dental Products Advisory Panel: “At that meeting [of the FDA Dental Products Advisory Panel where the partial TMJ prosthesis was considered] the FDA staff presentation expressed concern regarding the lack of data on the effect of the natural condyle articulating against a metal fossa, the limited number of patients with long-term follow-up, and the broad diagnosis of internal derangement as an indication for its use.  The panel expressed similar concerns about these issues, as well as the fact that the registry data provided in support of the product did not include all the patients treated and the sample size was insufficient for each of the individual indications.  They recommended clarification of the patient inclusion criteria in the clinical study, evaluation of failures and additional patient follow-up, more clearly defined indications for use of the device, and that a power analysis of the clinical data be done to place the pre-market approval in an approvable form.  However, despite these criticisms, and the panel’s opinion that adequate safety and effectiveness data for the given surgical indications were lacking, the device was approved by the FDA for distribution in February 2001”.

Laskin (2001) concluded that “there are insufficient data” to answer questions about the safety and effectiveness of the partial TMJ prosthesis.  “For example, how reliable are clinical data based on a registry that did not include all patients treated with the device, in which there was a very small number of total patients with serial data and even smaller numbers in each diagnostic subcategory, and where in 1 group of 97 patients with a diagnosis of internal derangement and/or inflammatory arthritis, only 30 % (12 subjects) had a follow-up of 3 or more years and 70 % were either lost to follow-up, withdrawn, or potentially lost to follow-up.  How can one make an informed decision with such information?”

The manufacturer subsequently submitted a post-approval study to the FDA on the long-term follow-up of patients with a variety of TMJ conditions treated with the partial TMJ prosthesis (Christensen, 2008).  A total of 145 subjects (228 joints) were evaluated immediately before surgery and at regular intervals after surgery for up to 3 years.  Success was measured as improvement of function and decrease in pain as measured on a visual analog scale (VAS), as well as improved incisor opening as measured with a Therabite Scale.  Subjects showed a 4.9-cm reduction of pain on a 10-cm VAS scale and a 5.0-cm reduction in diet restriction at 36 months.  Subjects who were admitted with an inter-incisal opening of less than or equal to 15 mm showed a 19.4 mm average improvement at 18 months and 17.4 mm average improvement at 36 months.  The manufacturer reported that 4.1 % (6 subjects) of partial joint replacement subjects experienced device-related events, a percentage that was not significantly different than the percentage of device-related events reported with total joint replacement subjects (11.5 %).  Limitations of the post-approval study were similar to those of the initial study submitted for FDA approval. In particular, less than half (44 %) of the 145 subjects enrolled in the study had pain, diet restriction, and incisal opening data through three years (36 months).

The manufacturer also submitted a post-approval study to the FDA on the long-term followup of patients with a variety of TMJ conditions who were treated with the total TMJ prosthesis (Christensen, 2008).  A total of 78 subjects (127 joints) were evaluated immediately before surgery and at regular intervals after surgery for up to 3 years.  Subjects showed a 4.9 cm reduction of pain and a 5.9 cm diet restriction at 36 months.  Subjects who were admitted with an interincisal opening of less than or equal to 15 mm showed a 16.8 mm average improvement at 18 months and 18.0 mm average improvement at 36 months.  Nine subjects (11.5 %) of total joint replacement subjects experienced device-related events.  Follow-up was incomplete, as just over half (54 %) of subjects had pain data and diet restriction data (54 % and 57 %, respectively) at 36 months, and half (50 %) of subjects with reduced inter-incisal openings had incisal opening data at 36 months.

An evaluation study has reported better post-surgical outcomes with the TMJ Concepts total joint prosthesis than the Christensen total joint prosthesis.  Wolford et al (2003) reported the results of a study comparing the Christensen total joint prosthesis (TMJ Inc., Golden, CO) with the TMJ Concepts total joint prosthesis (TMJ Concepts Inc, Camarillo, CA) in 45 patients, 23 of whom were treated with the Christensen prosthesis, and 22 of whom were treated with the TMJ Concepts Prosthesis.  The investigators reported that, although subjects treated with either total joint prosthesis showed good skeletal and occlusal stability, the subjects treated with the TMJ Concepts Prosthesis had statistically significant improved outcomes compared to subjects treated with the Christensen prosthesis with respect to post-surgical incisal opening (37.3 mm versus 30.1 mm, p = 0.008), pain (decrease of 3.1 versus 1.8 on 10 point VAS score, p = 0.042), jaw function (improvement of 3.0 versus 1.2 on a 10 point scale, p = 0.008), and diet (2.0 versus 1.8 on a 10-point scale, p = 0.021).  The investigators concluded “[a]s a result of our study, it appears that [TMJ Concepts Prosthesis] provides a more biologically accepted and functional prosthesis than the [Christensen prosthesis] for the complex TMJ patient.”

In a study that examined factors to consider in joint prosthesis systems, Wolford (2006) stated that metal-on-ultra-high-molecular-weight polyethylene (UMWPE) has shown negligible wear debris histologically in the TMJ, whereas the Christensen prosthesis often demonstrates visible and histological evidence of metallosis from wear debris.  Furthermore, the author stated that to appropriately evaluate the success of the Christensen products, independent researchers (not affiliated with TMJ Implants Inc.) must perform prospective studies, because the research data provided by the company are highly suspect.

The W. Lorenz total TMJ replacement system (Walter Lorenz Surgical, Inc., Jacksonville, FL) was approved by the FDA on September 21, 2005 the FDA for the functional reconstruction of diseased and/or damaged jaw joints.  Its 2 components (mandibular condyle and glenoid fossa) are available in multiple sizes as left- and right-side specific designs.  Approved indications for the W. Lorenz TMJ replacement system include arthritic conditions such as osteoarthritis, traumatic arthritis, or rheumatoid arthritis; ankylosis including but not limited to recurrent ankylosis with excessive heterotopic bone formation; and revision procedures in which other treatments have failed (e.g., alloplastic reconstruction, autogenous grafts).  The approval was based on data from a 6-year case series study of 224 patients (329 joints), showing that patients receiving the implant reported reduced pain, improved function, an increase in maximal incisal opening, as well as satisfaction with the outcome.

The device is not intended for partial TMJ reconstruction or for use in patients susceptible to infection or having active/chronic infection, insufficient bone to support the device, an immature skeleton, or hyper-functional habits such as clenching/grinding of teeth.  An evaluation of the W. Lorenz total TMJ replacement system by the Australian Department of Health and Aging (2006) stated that the only available study on this prosthesis was the case series included in the FDA safety and effectiveness summary.  The Australian Department of Health and Aging recommended monitoring of the continual development of this technology.

Certain other total joint prostheses, such as the Vitek-Kent total joint prosthesis (Vitek Inc, Houston, TX) and silastic implants, are not considered medically necessary as they have been removed from the market due to poor biocompatibility, increased wear, fragmentation, and foreign body giant cell reaction.

For persons who already have had implant or other invasive surgery, additional surgical interventions (with the possible exception of implant removal) should be considered only with great caution, since the evidence indicates that the probability of success decreases with each additional surgical intervention.  For these persons, available evidence indicates that the most promising immediately available treatment may be a patient-centered, multidisciplinary, palliative approach.

In a pilot study, Adiels and colleagues (2005) assessed if fibromyalgia syndrome (FMS) patients with signs and symptoms of TMD refractory to conservative TMD treatment would respond positively to tactile stimulation in respect of local and/or general symptoms.  A total of 10 female patients fulfilling the inclusion criteria received such treatment once-weekly during a 10-week period.  At the end of treatment, a positive effect on both clinical signs and subjective symptoms of TMD, as well as on general body pain, was registered.  Eight out of 10 patients also perceived an improved quality of their sleep.  At follow-ups after 3 and 6 months, some relapse of both signs and symptoms could be seen, but there was still an improvement compared to the initial degree of local and general complaints.  At the 6-month follow-up, half of the patients also reported a lasting improvement of their sleep quality.  One hypothetical explanation to the positive treatment effect experienced by the tactile stimulation might be the resulting improvement of the patients' quality of sleep leading to increased serotonin levels.  The authors concluded that "the results of the present pilot study are so encouraging that they warrant an extended, controlled study".

There is insufficient evidence in the literature to support the hypothesis that orthognathic surgical correction for TMJ abnormalities such as condylar hypertrophy, status post condylar fracture, ankylosis, etc., will predictably prevent or improve a temporomandibular dysfunction.  There is no body of evidence in the peer reviewed literature to suggest that orthognathic surgery is a curative modality for internal joint derangements of the temporomandibular joints.

A systemic review on malocclusions and orthodontic treatment by the Swedish Council on Technology Assessment in Health Care (SBU, 2005) concluded that the appearance of the teeth is the patients' most important reason for seeking orthodontic treatment.  In addition, scientific evidence is insufficient for conclusions on patient satisfaction in the log-term (at least 5 years) after the conclusion of orthodontic treatment.  Furthermore, the assessment stated that scientific evidence is insufficient for conclusions on a correlation between specific untreated malocclusions and symptomatic TMJ disorders.

In a Cochrane review on orthodontics for treating TMD, Luther et al (2010) examined the effectiveness of orthodontic intervention in reducing symptoms in patients with TMD (compared with any control group receiving no treatment, placebo treatment or reassurance) and whether active orthodontic intervention leads to TMD.  The Cochrane Oral Health Group's Trials Register, CENTRAL, MEDLINE and EMBASE were searched.  Hand-searching of orthodontic journals and other related journals was undertaken in keeping with the Cochrane Collaboration hand-searching program.  No language restrictions were applied.  Authors of any studies were identified, as were experts offering legal advice, and contacted to identify unpublished trials.  Most recent search was April 13, 2010.  All randomized controlled trials (RCTs) including quasi-randomized trials assessing orthodontic treatment for TMD were included.  Studies with adults aged equal to or above 18 years old with clinically diagnosed TMD were included.  There were no age restrictions for prevention trials provided the follow-up period extended into adulthood.  The inclusion criteria required reports to state their diagnostic criteria for TMD at the start of treatment and for participants to exhibit 2 or more of the signs and/or symptoms.  The treatment group included treatment with appliances that could induce stable orthodontic tooth movement.  Patients receiving splints for 8 to 12 weeks and studies involving surgical intervention (direct exploration/surgery of the joint and/or orthognathic surgery to correct an abnormality of the underlying skeletal pattern) were excluded.  Main outcome measures were how well the symptoms were reduced, adverse effects on oral health and quality of life.  Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted in triplicate and independently by 3 review authors.  As no 2 studies compared the same treatment strategies (interventions) it was not possible to combine the results of any studies.  The searches identified 284 records from all databases.  Initial screening of the abstracts and titles by all review authors identified 55 articles that related to orthodontic treatment and TMD.  The full articles were then retrieved and of these articles only 4 demonstrated any data that might be of value with respect to TMD and orthodontics.  After further analysis of the full texts of the 4 studies identified, none of the retrieved studies met the inclusion criteria and all were excluded from this review.  The authors concluded that there are insufficient research data on which to base their clinical practice on the relationship of active orthodontic intervention and TMD.  There is an urgent need for high quality RCTs in this area of orthodontic practice.  When considering consent for patients it is essential to reflect the seemingly random development/alleviation of TMD signs and symptoms.

da Cunha et al (2008) assessed the effectiveness of low-level laser therapy (LLLT) in patients presenting with TMD.  A total of 40 patients were randomized into an experimental group (G1) or a placebo group (G2).  The treatment was carried out with an infrared laser (830 nm, 500 mW, 20s, 4J/point) at the painful points, once-weekly for 4 consecutive weeks.  Patients were evaluated before and after the treatment through a VAS and the cranio-mandibular index (CMI).  The baseline and post-therapy values of VAS and CMI were compared by the paired t-test, separately for the placebo and laser groups.  A significant difference was observed between initial and final values (p < 0.05) in both groups.  Baseline and post-therapy values of pain and CMI were compared in the therapy groups by the 2-sample t-test, yet no significant differences were observed regarding VAS and CMI (p > 0.05).  The authors concluded that after either placebo or laser therapy, pain and temporomandibular symptoms were significantly lower, although there was no significant difference between groups.  The LLLT was ineffective for the treatment of TMD, when compared to the placebo.  This is in agreement with the findings of Emshoff et al (2008) who reported that LLLT is not better than placebo in reducing TMJ pain during function (n = 52).

In a randomized, double-blinded, placebo-controlled study, Castrillon et al (2008) examined the effect of peripheral N-methyl-D-aspartate (NMDA) receptor blockade with ketamine on chronic myofascial pain in patients with TMD.  A total of 14 patients (10 women and 4 men) were recruited.  The subjects completed 2 sessions in a double-blinded randomized and placebo-controlled trial.  They received a single injection of 0.2 ml ketamine or placebo (buffered isotonic saline, 155 mmol/l) into the most painful part of the masseter muscle.  The primary outcome parameters were spontaneous pain assessed on an electronic VAS and numeric rating scale.  In addition, numeric rating scale of unpleasantness, numeric rating scale of pain relief, pressure pain threshold (PPT), pressure pain tolerance, completion of a McGill Pain Questionnaire and pain drawing areas, maximum voluntary bite force and maximum voluntary jaw opening were obtained.  Paired t-tests and analysis of variance were performed to compare the data.  There were no main effects of the treatment on the outcome parameters except for a significant effect of time for maximum voluntary bite force (analysis of variance [ANOVA]; p = 0.030) and effects of treatment, time, and interactions between treatment and time for maximum voluntary jaw opening (ANOVA; p < 0.047).  The authors concluded that these findings suggest that peripheral NMDA receptors do not play a major role in the pathophysiology of chronic myofascial TMD pain.  Although there was a minor effect of ketamine on maximum voluntary jaw opening, local administration may not be promising treatment for these patients.

Al-Saleh et al (2012) noted that although electromyography (EMG) has been used extensively in dentistry to assess masticatory muscle impairments in several conditions, especially TMD, many investigators have questioned its psychometric properties and accuracy in diagnosing TMD.  These investigators performed a systematic review to analyze the literature critically and determine the accuracy of EMG in diagnosing TMDs.  They conducted an electronic search of Medline, Embase, all Evidence-Based Medicine Reviews, Allied and Complementary Medicine, Ovid HealthSTAR and SciVerse Scopus.  They selected abstracts that fulfilled the inclusion criteria, retrieved the original articles, verified the inclusion criteria and hand searched the articles' references.  They used a methodological tool (Quality Assessment of Diagnostic Accuracy Studies [QUADAS]) to evaluate the quality of the selected articles.  The electronic database search resulted in a total of 130 articles.  The authors selected 8 articles as potentially meeting eligibility for the review.  Of these 8 articles, only 2 fulfilled the study inclusion criteria, and the authors analyzed them.  Investigators in both studies reported low sensitivity (values ranged from 0.15 to 0.40 in 1 study and a mean of 0.69 in the second study).  In addition, investigators in the 2 studies reported contradictory levels of specificity (values ranged from 0.95 to 0.98 in 1 study, and the mean value in the 2nd study was 0.67).  The likelihood ratios and predictive values were not helpful in diagnosing TMD by means of EMG.  The quality of the 2 studies was poor on the basis of the QUADAS checklist.  The authors concluded that this systematic review found no evidence to support the use of EMG for the diagnosis of TMD.

Sharma et al (2013) conducted a systematic review of papers reporting the reliability and diagnostic validity of the joint vibration analysis (JVA) for diagnosis of TMD.  A search of PubMed identified English-language publications of the reliability and diagnostic validity of the JVA.  Guidelines were adapted from applied STAndards for the Reporting of Diagnostic accuracy studies (STARD) to evaluate the publications.  A total of 15 publications were included in this review, each of which presented methodological limitations.  The authors concluded that this literature review was unable to provide evidence to support the reliability and diagnostic validity of the JVA for diagnosis of TMD.

Hypnosis/Relaxation Therapy:

In a systematic review and meta-analysis, Zhang et al (2015) evaluated the effectiveness of hypnosis/relaxation therapy compared to no/minimal treatment in patients with TMD.  Studies reviewed included RCTs where investigators randomized patients with TMD or an equivalent condition to an intervention arm receiving hypnosis, relaxation training, or hypo-relaxation therapy, and a control group receiving no/minimal treatment.  The systematic search was conducted without language restrictions, in Medline, EMBASE, CENTRAL, and PsycINFO, from inception to June 30, 2014.  Studies were pooled using weighted mean differences and pooled risk ratios (RRs) for continuous outcomes and dichotomous outcomes, respectively, and their associated 95 % confidence intervals (CI).  Of 3,098 identified citations, 3 studies including 159 patients proved eligible, although none of these described their method of randomization.  The results suggested limited or no benefit of hypnosis/relaxation therapy on pain (risk difference in important pain -0.06; 95 % CI: -0.18 to 0.05; p = 0.28), or on PPTs on the skin surface over the TMJ and masticatory muscles.  Low-quality evidence suggested some benefit of hypnosis/relaxation therapy on maximal pain (mean difference on 100-mm scale = -28.33; 95 % CI: -44.67 to -11.99; p = 0.007) and active maximal mouth opening (mean difference on 100-mm scale = -2.63 mm; 95 % CI: -3.30 mm to -1.96 mm; p < 0.001) compared to no/minimal treatment.  The authors concluded that 3 RCTs were eligible for the systematic review, but they were with high risk of bias and provided low-quality evidence, suggesting that hypnosis/relaxation therapy may have a beneficial effect on maximal pain and active maximal mouth opening but not on pain and PPT.  They stated that larger RCTs with low risk of bias are needed to confirm or refute these findings and to inform other important patient outcomes.

Manual Therapy:

Calixtre et al (2015) stated that there is a lack of knowledge about the effectiveness of manual therapy (MT) on subjects with TMD.  These investigators synthetized evidence regarding the isolated effect of MT in improving maximum mouth opening (MMO) and pain in subjects with signs and symptoms of TMD.  MEDLINE, Cochrane, Web of Science, SciELO and EMBASE electronic databases were consulted, searching for RCTs applying MT for TMD compared to other intervention, no intervention or placebo.  Two authors independently extracted data, PEDro scale was used to assess risk of bias, and GRADE (Grading of Recommendations Assessment, Development and Evaluation) was applied to synthetize overall quality of the body of evidence.  Treatment effect size was calculated for pain, MMO and PPT.  A total of 8 trials were included, 7 of high methodological quality.  Myofascial release and massage techniques applied on the masticatory muscles are more effective than control (low-to-moderate evidence) but as effective as toxin botulinum injections (moderate evidence).  Upper cervical spine thrust manipulation or mobilization techniques are more effective than control (low-to-high evidence), while thoracic manipulations are not.  There is moderate-to-high evidence that MT techniques protocols are effective.  The methodological heterogeneity across trials protocols frequently contributed to decreased quality of evidence.  The authors concluded that there is widely varying evidence that MT improves pain, MMO and PPT in subjects with TMD signs and symptoms, depending on the technique.  They stated that further studies should consider using standardized evaluations and better study designs to strengthen clinical relevance.

Armijo-Olivo and colleagues (2016) summarized evidence from and evaluated the methodological quality of RCTs that examined the effectiveness of MT and therapeutic exercise interventions when compared with other active interventions or standard care for treatment of TMD.  Electronic data searches were performed including 6 databases in addition to manual search; RCTs involving adults with TMD, comparing any type of MT intervention (e.g., mobilization, manipulation) or exercise therapy compared to a placebo intervention, controlled comparison intervention, or standard care were included.  The main outcomes of this systematic review were pain, range of motion (ROM) and oral function.  A total of 48 studies met the inclusion criteria and were analyzed.  Data were extracted in duplicate on specific study characteristics.  The overall evidence for this systematic review was considered low.  The trials included in this review had unclear or high risk of bias.  Thus, the evidence was generally down-graded based on risk of bias assessments.  Most of the effect sizes were low-to-moderate with no clear indication of superiority of exercises versus other conservative treatments to treat TMD.  However, MT alone or in combination with exercises at the jaw or cervical level showed promising effects.  The authors concluded that no high quality evidence was found, indicating that there is great uncertainty about the effectiveness of exercise and manual therapy for TMD.

Permanent Mandibular Repositioning:

Greene and Obrez (2015) reviewed the rationale and history of mandibular repositioning procedures in relation to TMDs as these procedures have evolved over time.  A large body of clinical research evidence showed that most TMDs can and should be managed with conservative treatment protocols that do not include any mandibular repositioning procedures.  Although this provided a strong clinical argument for avoiding such procedures, very few reports have discussed the biologic reasons for either accepting or rejecting them.  This scientific information could provide a basis for determining whether mandibular repositioning procedures can be defended as being medically necessary.  This position paper introduced the biologic concept of homeostasis as it applies to this topic.  The continuing adaptability of teeth, muscles, and temporomandibular joints throughout life is described in terms of homeostasis, which leads to the conclusion that each person's current temporomandibular joint position is biologically "correct".  Therefore, that position does not need to be changed as part of a TMD treatment protocol.  This means that irreversible TMD treatment procedures, such as equilibration, orthodontics, full-mouth reconstruction, and orthognathic surgery, cannot be defended as being medically necessary.

Phototherapy:

Herpich et al (2014) stated that according to the International Association for the Study of Pain (IASP), the term TMD regards a subgroup of orofacial pain, the symptoms of which include pain or discomfort in the temporomandibular joint, ears, masticatory muscles and neck on one or both sides, as well as joint sounds, limited mandibular movements or mandibular deviation and difficulties chewing.  Phototherapy, such as low-level laser therapy (LLLT) and light-emitting diode (LED) therapy, is one of the resources used to treatment muscle pain.  Thus, there is a need to investigate therapeutic resources that combine different wavelengths as well as different light sources (LLLT and LED) in the same apparatus.  The aim of the proposed study is to evaluate the effects of 4 different doses of phototherapy on pain, activity of the masticatory muscles (masseter and bilateral anterior temporal) and joint mobility in individuals with TMD.  A further aim is to determine the cumulative effect 24 and 48 hours after a single session.  A placebo-controlled, double-blind, randomized, clinical trial will be carried out involving 72 women between 18 and 40 years of age with a diagnosis of myogenous TMD.  The participants will then be randomly allocated to 4 groups totaling 18 individuals per group; 3 groups will be submitted to a single session of phototherapy with different light sources, and 1 group will receive placebo therapy: Group A (2.62 Joules); Group B (5.24 Joules); Group C (7.86 Joules); and Group D (0 Joules).  The following assessment tools will be administered on 4 separate occasions (baseline and immediately after, 24 hours after and 48 hours after phototherapy).  Pain intensity will be assessed using the VAS for pain, while pain thresholds will be determined using algometer, and EMG analysis on the masseter and anterior temporal muscles.  The study will contribute to the practice of the evidence-based use of phototherapy in individuals with a myogenous TMD.  Data will be published after the study is completed.  This study is registered with the Brazilian Registry of Clinical Trials, NCT02018770, date of registration: December 7, 2013.

Stem Cell Therapy:

Zhang et al (2015) noted that in the past decade, progress made in the development of stem cell-based therapies and tissue engineering have provided alternative methods to attenuate the disease symptoms and even replace the diseased tissue in the treatment of TMJ disorders.  Resident mesenchymal stem cells (MSCs) have been isolated from the synovia of TMJ, suggesting an important role in the repair and regeneration of TMJ.  The seminal discovery of pluripotent stem cells including embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) have provided promising cell sources for drug discovery, transplantation as well as for tissue engineering of TMJ condylar cartilage and disc.  The authors discussed the most recent advances in development of stem cell-based treatments for TMJ disorders through innovative approaches of cell-based therapeutics, tissue engineering and drug discovery.  The effectiveness of stem cell therapy for the treatment of TMD has yet to be determined.

Transcranial Direct Current Stimulation:

Oliveira et al (2015) evaluated the effect of adding transcranial direct current stimulation (tDCS) to exercises for chronic pain, dysfunction and quality of life in subjects with TMD.  Participants were selected based on the Research Diagnostic Criteria (RDC)/TMD criteria and assessed for pain intensity, PPT over temporomandibular joint and cervical muscles and quality of life.  After initial assessment, all individuals underwent a 4-week protocol of exercises and MT, together with active or sham primary motor cortex tDCS.  Stimulation was delivered through sponge electrodes, with 2 mA amplitude, for 20 mins daily, over the first 5 days of the trial.  A total of 32 subjects (mean age of 24.7 ± 6.8 years) participated in the evaluations and treatment protocol.  Mean pain intensity pre-treatment was 5.5 ± 1.4 for active tDCS group, and 6.3 ± 1.2 for sham tDCS.  Both groups showed a decrease in pain intensity scores during the trial period (time factor - F4.5, 137.5 = 28.7, p < 0·001; group factor - F1.0, 30.0 = 7.7, p < 0.05).  However, there were no differences between the groups regarding change in pain intensity (time*group interaction - F4.5, 137.5 = 1.5, p = 0.137).  This result remained the same after 5 months (t-test t = 0.29, p > 0.05).  Pressure pain thresholds decrease and improvement in quality of life were also noticeable in both groups, but again without significant differences between them.  Absolute benefit increase was 37.5 % (CI 95 %: -15.9 % to 90.9 %), and number needed to treat was 2.66.  The authors concluded that the findings of this study suggested that there is no additional benefit in adding tDCS to exercises for the treatment of chronic TMD in young adults.

Brandao Filho et al (2015) examine if cathodal tDCS over the dorsolateral prefrontal cortex has an analgesic effect on chronic TMD pain.  The investigators will run a randomized, controlled, cross-over, double-blind study with 15 chronic muscular TMD subjects.  Each subject will undergo active (1 mA and 2 mA) and sham tDCS.  Inclusion criteria will be determined by the RDC for TMD questionnaire, with subjects who have a pain VAS score of greater than 4/10 and whose pain has been present for the previous 6 months, and with a State-Trait Anxiety Inventory score of more than 42.  The influence of tDCS will be assessed through a VAS, quantitative sensory testing, quantitative electroencephalogram, and the State-Trait Anxiety Inventory score.  Some studies have demonstrated a strong association between anxiety/depression and chronic pain, where one may be the cause of the other.  This is especially true in chronic TMD, and breaking this cycle may have an effect over the symptoms and associated dysfunction.  The authors believe that by inhibiting activity of the dorsolateral prefrontal cortex though cathodal tDCS, there may be a change in both anxiety/depression and pain level.  They state that tDCS may emerge as a new tool to be considered for managing these patients.  These investigators envision that the information obtained from this study will provide a better understanding of the management of chronic TMD.  This trial was registered at clinicaltrials.gov on May 24, 2014 (Identifier: NCT02152267).

Somatosensory Testing:

In a cross-over, double-blinded, placebo-controlled manner, Ayesh and associates(2008) studied the effect of intra-articular ketamine on TMJ pain and somatosensory function.  Spontaneous pain and pain on jaw function was scored by patients on 0 to 10 cm VAS for up to 24 hours.  Quantitative sensory tests: tactile, pin-prick, PPT and pressure pain tolerance were used for assessment of somatosensory function at baseline and up to 15 mins after injections.  There were no significant effects of intra-articular ketamine over time on spontaneous VAS pain measures (ANOVA: p = 0.532), pain on jaw opening (ANOVA: p = 0.384), or any of the somatosensory measures (ANOVA: p > 0.188).  The poor effect of ketamine could be due to involvement of non-NMDA receptors in the pain mechanism and/or ongoing pain and central sensitization independent of peripheral nociceptive input.  The authors concluded that there appears to be no rationale to use intra-articular ketamine injections in TMJ arthralgia patients, and peripheral NMDA receptors may play a minor role in the pathophysiology of this disorder.

Kothari and colleagues (2015) noted that the pathophysiology and underlying pain mechanisms of TMD are poorly understood.  These researchers evaluated somatosensory function at the TMJs (TMJs) and examined if conditioned pain modulation (CPM) differs between TMD pain patients (n = 34) and healthy controls (n = 34).  Quantitative sensory testing was used to assess the somatosensory function. Z-scores were calculated for patients based on reference data.  Conditioned pain modulation was tested by comparing pressure pain thresholds (PPTs) before, during, and after the application of painful and non-painful cold stimuli.  Pressure pain thresholds were measured at the most painful TMJ and thenar muscle (control).  Data were analyzed with analyses of variance.  Most (85.3 %) of the patients exhibited at least 1 or more somatosensory abnormalities at the most painful TMJ with somatosensory gain with regard to PPT and punctate mechanical pain stimuli, and somatosensory loss with regard to mechanical detection and vibration detection stimuli as the most frequent abnormalities.  There was a significant CPM effect (increased PPT) at both test sites during painful cold application in healthy controls and patients (p < 0.001).  There was no significant difference in the relative CPM effect during painful cold application between groups (p = 0.227).  The authors concluded that somatosensory abnormalities were commonly detected in TMD pain patients and CPM effects were similar in TMD pain patients and healthy controls.

Genetic Testing:

Sangani and associates (2015) stated that the TMJ is a bilateral synovial joint between the mandible and the temporal bone of the skull and TMDs are a set of complicated and poorly understood clinical conditions, in which TMDs are associated with a number of symptoms including pain and limited jaw movement.  The increasing scientific evidence suggests that genetic factors play a significant role in the pathology of TMDs.  However, the underlying mechanism of TMDs remains largely unknown.  These researchers determined the associated genes to TMDs in humans and animals.  The literature search was conducted through databases including Medline (Ovid), Embase (Ovid), and PubMed (NLM) by using scientific terms for TMDs and genetics in March 2015.  Additional studies were identified by searching bibliographies of highly relevant articles and Scopus (Elsevier).  Systematic analyses identified 31 articles through literature searches, and a total of 112 genes were identified to be significantly and specifically associated with TMDs.  The authors concluded that this systematic review provided a list of accurate genes associated with TMDs and suggested a genetic contribution to the pathology of TMDs.

Hattori and colleagues (2015) noted that synovial fibroblasts contribute to the inflammatory TMJ under pathogenic stimuli.  Synovial fibroblasts and T cells participate in the perpetuation of joint inflammation in a mutual activation feedback, via secretion of cytokines and chemokines that stimulate each other.  IL-17 is an inflammatory cytokine produced primarily by Th17 cells that plays critical role in the pathogenesis of numerous autoimmune and inflammatory diseases.  These researchers investigated the roles of IL-17A in TMD using genome-wide analysis of synovial fibroblasts isolated from patients with TMD.  IL-17 receptors were expressed in synovial fibroblasts as assessed using real-time polymerase chain reaction (PCR).  Microarray analysis indicated that IL-17A treatment of synovial fibroblasts up-regulated the expression of IL-6 and chemokines.  Real-time PCR analysis showed that the gene expression of IL-6, CXCL1, IL-8, and CCL20 was significantly higher in IL-17A-treated synovial fibroblasts compared to non-treated controls.  IL-6 protein production was increased by IL-17A in a time- and a dose-dependent manner.  Additionally, IL-17A simulated IL-6 protein production in synovial fibroblasts samples isolated from 3 patients.  Furthermore, signal inhibitor experiments indicated that IL-17-mediated induction of IL-6 was transduced via activation of NFκB and phosphatidylinositol 3-kinase/Akt.  The authors concluded these results suggested that IL-17A is associated with the inflammatory progression of TMD.

Nicot and co-workers (2016) stated that dento-facial deformities are dysmorpho-functional disorders involving the TMJ.  Many investigators have reported a TMJ improvement in dysfunctional subjects with malocclusion after orthodontic or combined orthodontic and surgical treatment particularly for the relief of pain.  In particular, few studies have highlighted the demographic and clinical predictors of response to surgical treatment.  To-date, no genetic factor has yet been identified as a predictor of response to surgical treatment.  These researchers identified single-nucleotide polymorphisms (SNPs) associated with post-operative TMD or with TMJ symptoms after orthognathic surgery.  They found the AA genotype of SNP rs1643821 (ESR1 gene) as a risk factor for dysfunctional worsening after orthognathic surgery.  In addition, they have identified TT genotype of SNP rs858339 (ENPP1 gene) as a protective factor against TMD in a population of patients with dento-facial deformities.  Conversely, the heterozygous genotype AT was identified as a risk factor of TMD with respect to the rest of the population.  All these elements are particularly important to bring new screening strategies and tailor future treatment.  The authors concluded that the findings of this study helped to identify sub-populations at high risk of developing post-operative temporomandibular disorders after orthognathic surgery procedures.  Moreover, they stated that many other genes of interest could be potential factors influencing the dysfunctional response to orthognathic surgery, particularly genes of the Opera cohort.

Yilmaz and colleagues (2016) noted that TMJ internal derangement (TMJ ID) is a multi-factorial complex disease characterized by articular disc degeneration.  Matrilin-3 is a cartilage and bone-specific adaptor protein, and amino-acid substitutions in the protein are associated with skeletal diseases and joint disorders.  These investigators examined the variants of Matrilin-3 gene (MATN3) in a TMJ ID case-control group and investigated the risk association of the detected variants with TMJ ID.  A case control study was conducted consisting of 57 unrelated TMJ ID patients (32.7 ± 8.2) and 96 unrelated healthy controls (26.63 ± 3.05) without TMJ ID to look for associations with variants of the MATN3 gene.  DNA from individual subjects was extracted and each of the 8 exons was amplified by PCR and analyzed by single-strand conformation polymorphism (SSCP) analysis.  SSCP variants were subjected to DNA sequence analysis, which yielded band pattern variations in exon 2 of the gene.  These researchers further analyzed exon 2 by DNA sequencing to determine the sequence of these variants.  They identified SSCP band patterns variants in exon 2 of the MATN3 gene, which upon sequencing revealed a single C to T transition mutation (rs28598872) c.447 C>T (g.11608 C>T).  This polymorphism is predicted to result in a synonymous mutation (pAla149 = ).  The TT and CT genotypes were more prevalent than the CC genotype in TMJ ID patients compared to the control group with a risk factor of 2.12 (CI: 0.88 to 5.08) and 2.0 (CI: 0.726 to 5.508).  In addition, TMJ ID patients were divided into 2 groups as anterior disc displacement with reduction (ADDWR) and anterior disc displacement without reduction (ADDWOR) and compared with the controls.  The TT and CT genotypes were more prevalent than the CC genotype in ADDWR patients compared to the control group with a risk factor of 3.85 (CI: 0.927 to 16.048) and 3.75 (1.02 to 13.786), respectively.  These investigators found that, among ADDWR patients, the T allele is a risk factor both in homozygous and heterozygous carriers (p < 0.052, p < 0.036).  The authors concluded that the findings of this study indicated a potential role for the MATN3 rs28598872 polymorphism in the pathogenesis of TMJ ID.

Melis and Di Giosia (2016) performed a review of the literature of published articles assessing the role of genetic factors in the etiology of TMDs.  A PubMed search was carried out by looking for all controlled clinical trials related to the topic and limiting the search to English language and humans.  The references from the studies included and those from review articles were also examined for further relevant papers.  A total of 1,999 articles were first identified, 24 of which were considered relevant to the topic; 2 other papers were found while searching the references.  While TMD signs and symptoms' co-occurrence was not found in subjects within the same family, many gene polymorphisms were shown to be associated with a higher or lower risk of TMD.  Such genes were mainly related to serotonin activity and metabolism, T-cell receptor pathway, catecholamine activity and metabolism, estrogen activity, folate metabolism, glutathione activity, ANKH gene, major histocompatibility complex, extracellular matrix metabolism, genes studied in the orofacial pain prospective evaluation risk and assessment (OPPERA) study, and related to cytokines activity and metabolism.  The authors concluded that this new understanding of the pathophysiology of TMD can lead to a different treatment approach by identifying the subjects at higher risk for this pathology, and possibly by creating new drugs targeted at interfering with the expression of the genes that enhance such risk.

Furthermore, an UpToDate review on “Temporomandibular disorders in adults” (Scrivani and Mehta, 2016) does not mention genetic testing as a management tool.

Measurement of Circulating Omentin-1:

In a case-control study, Harmon and colleagues (2016) examined the relationship between omentin-1 levels and painful TMD.  Chronic painful TMD cases (n = 90) and TMD-free controls (n = 54) were selected from participants in the multi-site OPPERA study.  Painful TMD case status was determined by examination using established Research Diagnostic Criteria for TMD (RDC/TMD).  Levels of omentin-1 in stored blood plasma samples were measured by using an enzyme linked immune-sorbent assay (ELISA).  Binary logistic regression was used to calculate the odds ratios (ORs) and 95 % CIs for the association between omentin-1 and painful TMD.  Models were adjusted for study site, age, sex, and body mass index (BMI).  The unadjusted association between omentin-1 and chronic painful TMD was statistically non-significant (p = 0.072).  Following adjustment for covariates, odds of TMD pain decreased 36 % per standard deviation increase in circulating omentin-1 (adjusted OR = 0.64; 95 % CI: 0.43 to 0.96; p = 0.031).  The authors concluded that circulating levels of omentin-1 were significantly lower in painful TMD cases than controls, suggesting that TMD pain is mediated by inflammatory pathways.

Botulinum Toxin:

In a systematic review, Chen and associates (2015) evaluated the effectiveness of botulinum toxin therapy (BTX) for TMDs.  A comprehensive search of major databases through PubMed, Embase, and Cochrane CENTRAL was conducted to locate all relevant articles published from inception to October 2014.  Eligible studies were selected based on inclusion criteria and included English language, peer-reviewed publications of RCTs comparing BTX versus any alternative intervention or placebo.  Quality assessment and data extraction were done according to the Cochrane risk of bias tool and recommendations.  The entire systematic search and selection process was done independently by 2 reviewers.  A total of 5 relevant study trials were identified, involving 117 participants; 2 trials revealed a significant between-group difference in myofascial pain reduction, another trial that compared BTX with fascial manipulation showed equal effectiveness of pain relief on TMDs, while the remaining 2 trials showed no significant difference between the BTX and placebo groups.  Because of considerable variations in study methods and evaluation of results, a meta-analysis could not be performed.  The authors concluded that based on this review, no consensus could be reached on the therapeutic benefits of BTX on TMDs; a more rigorous design of trials should be performed in future studies.

Keenan (2015) evaluated the evidence on the use of BTX for TMD pain.  The author performed a comprehensive search on major databases such as PubMed, Embase and Cochrane CENTRAL.  Reference lists of the included studies were explored along with journals likely to contain studies relevant to the topic.  The search was restricted to the English language.  The inclusion criteria included RCTs and quasi-RCTs including parallel or cross-over studies comparing BTX versus any alternative intervention or placebo.  Quality assessment and data extraction were done following the Cochrane risk of bias tool and recommendations.  All of the steps in the review, including the search and selection process, were done independently by 2 reviewers.  Disagreements were discussed with one another until consensus was reached.  A total of 5 relevant studies were included in the review, which consisted of 117 participants; 2  trials revealed a significant inter-group difference in myofascial pain reduction.  Another trial that compared BTX with fascial manipulation showed no significant difference in pain relief for TMDs, while the remaining 2 trials showed no significant difference between the BTX and placebo groups.  Meta-analysis was not performed due to the considerable variation in study methods and evaluation of the results.  All 5 studies were targeted primarily on the masseter and temporalis muscles and most of them administered injections at bilateral muscle sites.  The methods used to find the muscles to target were all based on physical examination, with 3 studies using EMG as guidance.  The dose of BTX ranged from 70 U to 300 U, the majority used being 100 to 150 U.  All studies gave a single session of BTX and re-evaluated participants at least 1 month following the injection.  The authors concluded that no consensus could be reached on the therapeutic benefit of BTX on TMDs.

Injection of Plasma Rich in Growth Factors:

In a randomized, prospective clinical study, Fernandez Sanroman and colleagues (2016) evaluated the effectiveness of injection of plasma rich in growth factors (PRGF) after TMJ arthroscopy in patients with Wilkes stage IV internal derangement.  A total of 92 patients were randomized to 2 experimental groups: group A (42 joints) received injections of PRGF, and group B (50 joints) received saline injections.  Pain intensity on a VAS and MMO (mm) were measured before and after surgery and compared by analysis of variance (ANOVA).  The mean age of patients was 35.8 years (range of 17 to 67 years); 86 were female.  Significant reductions in pain were noted in both groups after surgery: VAS 7.9 pre-operative and 1.4 at 24 months post-operative.  Significantly better clinical results were achieved in group A than in group B only at 6 and 12 months post-operative; no significant difference was noted at 18 or 24 months after the surgical intervention; MMO increased after surgery in both groups: 26.2 mm pre-operative and 36.8 mm at 24 months post-operative.  No significant differences in MMO were found when the 2 groups of patients were compared.  The authors concluded that the injection of PRGF did not add any significant improvement to clinical outcomes at 2 years after surgery in patients with advanced internal derangement of the TMJ.

Intra-Articular Injections of Hyaluronic Acid:

In a systematic review, Manfredini and colleagues (2010) examined the clinical studies on the use of hyaluronic acid (HA) injections to treat TMJ disorders performed over the last decade.  The selected papers were assessed according to a structured reading of articles format, which provided that the study design was methodologically evaluated in relation to 4 main issues: (i) population, (ii) intervention, (iii) comparison, and (iv) outcome.  A total of 19 papers were selected for inclusion in the review, 12 dealt with the use of HA in TMJ disk displacements and 7 dealt with inflammatory-degenerative disorders.  Only 9 groups of researchers were involved in the studies, and less than 50 % of the studies (8/19) were randomized and controlled trials.  All studies reported a decrease in pain levels independently by the patients' disorder and by the adopted injection protocol.  Positive outcomes were maintained over the follow-up period, which ranged between 15 days and 24 months.  The superiority of HA injections was shown only against placebo saline injections, but outcomes are comparable with those achieved with corticosteroid injections or oral appliances.  The available literature seems to be inconclusive as to the effectiveness of HA injections with respect to other therapeutic modalities in treating TMJ disorders.  The authors concluded that studies with a better methodological design are needed to gain better insight into this issue and to draw clinically useful information on the most suitable protocols for each different TMJ disorder..

Goiato and colleagues (2016) examined if intra-articular (IA) injections of HA are better than other drugs used in TMJ arthrocentesis, for the improvement of TMD symptoms. Two independent reviewers performed an electronic search of the Medline and Web of Science databases for relevant studies published in English up to March 2016.  The key words used included a combination of “hyaluronic acid”, “viscosupplementation”, “intra-articular injections”, “corticosteroids”, or “nonsteroidal anti-inflammatory agents” with “temporomandibular disorder”.  Selected studies were RCTs and prospective or retrospective studies that primarily investigated the application of HA injections compared to other IA medications for the treatment of TMD.  The initial screening yielded 523 articles.  After evaluation of the titles and abstracts, 8 were selected.  Full texts of these articles were accessed and all fulfilled the inclusion criteria.  These researchers found that IA injections of HA were beneficial in improving the pain and/or functional symptoms of TMDs.  However, other drug therapies (e.g., corticosteroid and NSAID injections), can be used with satisfactory results.  The authors concluded that well-designed clinical studies are needed to identify an adequate protocol, the number of sessions needed, and the appropriate molecular weight of HA for use.

Intra-Articular Injections of Rituximab:

In a retrospective study, Stoll and colleagues (2015) evaluated the involvement of IA infliximab (IFX) in the management of TMJ arthritis associated with juvenile idiopathic arthritis (JIA) that is refractory to systemic treatment and IA corticosteroid therapy.  Subjects were children with JIA who received IA IFX into the TMJ.  The effectiveness of treatment on the progression of acute and chronic changes was assessed by a quantitative MRI scoring system.  Median acute and chronic scores worsened by 0.25 and 0.75, respectively.  In multi-variate analysis, worsening acute scores and passage of time predicted worsening of the chronic scores.  The authors concluded that IA IFX allowed for progression of refractory TMJ arthritis in most but not all children with JIA.

Platelet-Rich Plasma:

Pihut et al (2014) evaluated the regression of temporo-mandibular pain as a result of intra-articular injections of platelet-rich plasma (PRP) to patients with TMJ dysfunction previously subjected to prosthetic treatment.  The baseline study material consisted of 10 patients, aged 28 to 53 years, previously treated due to painful TMJ dysfunction using occlusal splints.  All patients underwent a specialist functional assessment of the dysfunction using the Polish version of the RDC/TMD questionnaire axis I and II.  The injection sites were determined by the method used during arthroscopic surgical procedures.  Following aspiration, 0.5 ml of PRP was injected into each TMJ.  The comparison of the intensity of pain during all examinations suggested a beneficial effect of the procedure being performed as the mean VAS score was 6.5 at examination I, 2.8 at examination II, and 0.6 at examination III.  The authors concluded that the application of the intra-articular injections of PRP into the TMJs has a positive impact on the reduction of the intensity of pain experienced by patients treated for TMJ dysfunction.  These preliminary findings need to be validated by well-designed studies.

In a systematic review, Bousnaki and Koidis (2017) examined if intra-articular injections of PRP are beneficial for the treatment of degenerative TMDs, such as TMJ osteoarthritis (TMJ-OA) and disc displacement with osteoarthritic lesions, when compared to other treatments, such as injections of HA or saline.  These researchers carried out an electronic search of the Medline and Scopus databases using combinations of the terms "temporomandibular" and "platelet rich plasma", to identify studies reported in English and published up until May 2017.  A hand-search of relevant journals and the reference lists of selected articles was also performed.  The initial screening identified 153 records, of which only 6 fulfilled the inclusion criteria and were included in this review.  Of these studies, 3 compared PRP with HA, while 3 compared PRP with Ringer's lactate or saline; 4 of the studies found PRP injections to be superior in terms of improvements in mandibular ROM and pain intensity up to 12 months after treatment, while the remaining 2 studies found similar results for the different treatments.  The authors concluded that there is slight evidence for the potential benefits of intra-articular injections of PRP in patients with TMJ-OA.  However, they stated that a standardized protocol for PRP preparation and application needs to be established.

Salivary Stress Biomarkers:

Kobayashi and colleagues (2017) noted that the etiology of TMD remains a controversial issue in clinical dentistry.  These researchers examined if salivary alpha-amylase (sAA), cortisol levels, and anxiety symptoms differ between children with and without TMD.  Initially, 316 young subjects were screened in public schools (non-referred sample); 76 subjects aged 7 to 14 years were selected and comprised the TMD and control groups with 38 subjects each matched by sex, age, and the presence/absence of sleep bruxism.  Four saliva samples were collected: upon waking, 30 mins and 1 hour after awakening (fasting), and at night (at 8 PM) on 2 alternate days to examine the diurnal profiles of cortisol and sAA.  Anxiety symptoms were screened using the Multidimensional Anxiety Scale for Children (MASC-Brazilian version).  Shapiro-Wilk test, Student's t-test/Mann-Whitney U test, and correlation tests were used for data analysis.  No significant differences were observed in the salivary cortisol area under the curve (AUCG mean ± SD = 90.22 ± 63.36 × 94.21 ± 63.13 µg/dL/min) and sAA AUCG (mean ± SD = 2,544.52 ± 2,142.00 × 2,054.03 ± 1,046.89 U/mL/min) between the TMD and control groups, respectively (p > 0.05); however, the clinical groups differed in social anxiety domain (t = 3.759; CI: 2.609 to 8.496), separation/panic (t = 2.243; CI: 0.309 to 5.217), physical symptoms (U = 433.500), and MASC total score (t = -3.527; CI: -23.062 to -6.412), with a power of the test greater than 80 % and large effect size (d = 0.80), with no significant correlation between the MASC total score, cortisol, and sAA levels.  The authors concluded that although children with TMD scored higher in anxiety symptoms, no difference was observed in the salivary stress biomarkers between children with and without TMD.

Bio-Oxidative Ozone Therapy:

In a double-blind, randomized clinical trial, Celakil and colleagues (2017) examined the effect of bio-oxidative ozone application at the points of greatest pain in patients with chronic masticatory muscle pain.  A total of 40 women (mean age of 31.7) were selected after the diagnosis of myofacial pain dysfunction syndrome according to the Research Diagnostic Criteria for TMD (RDC/TMD).  Patients were randomly divided into 2 groups:

1. patients received the ozone therapy at the point of greatest pain, ozone group (OG; n = 20); and
2. patients received the sham ozone therapy at the point of greatest pain, placebo group (PG; n = 20). 

Ozone and placebo were applied 3 times/week, for a total of 6 sessions.  Mandibular movements were examined, masticator muscles tenderness were assessed and PPT values were obtained.  Subjective pain levels were evaluated using VAS.  These assessments were performed at baseline, 1 month and 3 months.  Ozono therapy decreased pain intensity and increased PPT values significantly from baseline to 1 month and 3 months in OG compared with PG; PPTs of the temporal (OG = 24.85 ± 6.65, PG = 20.65 ± 5.43, p = 0.035) and masseter (OG = 19.03 ± 6.42, PG = 14.23 ± 2.95, p = 0.007) muscles at 3 months of control (T2) were significantly higher in the OG group.  PPT value of the lateral pole was also significantly higher at T2 in the OG group (OG = 21.25 ± 8.43, PG = 15.35 ± 4.18, P = 0.012).  Mandibular movements did not show significant differences between treatment groups except right lateral excursion values at T2 (OG = 8.90 ± 1.77, PG = 6.85 ± 2.41, p = 0.003); however, OG demonstrated significantly better results over time.  Overall improvements in VAS scores from baseline to 3 months were OG 67.7 %; PG 48.4 %.  The authors concluded that although ozone therapy can be accepted as an alternative treatment modality in the management of masticatory muscle pain, sham ozone therapy (placebo) showed significant improvements in the tested parameters.  The main drawbacks of this study were its small sample size (n = 20 for the ozone group) and short-term follow-up (3 months).  These preliminary findings need to be validated in well-designed studies.

Magnetic Neurostimulator:

Florian and colleagues (2017) evaluated application of the magnetic neurostimulator (Haihua model CD-9), used within the precepts of acupuncture, in treating TMD-related pain symptoms and limited mouth opening.  Analysis and discussion of this study were based on pain intensity index and range of mouth-opening evaluation before and after each session.  A total of 9 patients diagnosed with muscle TMD, referred by the surgery sector of Center Dental Specialties (CEO - I) in Piracicaba-Sao Paulo participated in this research.  The authors concluded that considering the simplicity of the technique and good results obtained, use of this device is suggested as an additional therapeutic tool for relief of TMD symptoms.  These preliminary findings need to be validated in well-designed studies.

MIRO Therapy:

MIRO therapy entails the following:

• Transcutaneous neural stimulations (TENS) to relax your muscles, increase blood flow and remove waste products.
• TENS to relieve pain by stimulating the release of endorphins, your body’s own natural pain killer.
• Energex pulsed radio frequency energy to reduce pain and rapidly improve symptoms. In a recent study by Tufts University School of Dental Medicine, Energex therapy was found to be highly effective in reducing pain associated with TMJ arthralgia and improving range of motion in the joint.
• Vectra Genisys Ultrasound to reduce joint inflammation, muscle spasms and adhesions using sound waves that gently pass through your tissue to accelerate healing and repair.
• A clear, almost invisible temporary device worn over your lower teeth to correct improper alignment of your jaw without altering any of your actual teeth.
• Stabilize and refine your bite with periodic adjustments to the device until your symptoms are relieved or resolved.
• Find the exact position where your muscles and joints are most comfortable to stop the cycle of pain, pills and dysfunction.
• Multi Radiance cold laser to promote tissue healing and repair.
• NuCalm neuroscience technology to quickly produce deep relaxation of your muscles.

There is a lack of evidence regarding the effectiveness of MIRO therapy for the treatment of TMD/TMJ dysfunctions.

Table: CPT Codes / HCPCS Codes / ICD-10 Codes

Code	Code Description
Information in the [brackets] below has been added for clarification purposes.   Codes requiring a 7th character are represented by "+":
CPT codes covered if selection criteria are met:
20552	Injection(s); single or multiple trigger point(s), 1 or 2 muscle(s)
20553	single or multiple trigger point(s), 3 or more muscles
20605	Arthrocentesis, aspiration and/or injection, intermediate joint or bursa (eg, temporomandibular, acromioclavicular, wrist, elbow or ankle, olecranon bursa); without ultrasound guidance [not covered for viscosupplementation injection] [not covered for intra-articular injections of rituximab]
20910	Cartilage graft; costochondral [autologous]
21010	Arthrotomy, tempomandibular joint
21050	Condylectomy, tempomandibular joint (separate procedure)
21060	Meniscectomy, partial or complete, tempomandibular joint (separate procedure)
21070	Coronoidectomy (separate procedure)
21073	Manipulation of temporomandibular joint(s) (TMJ), therapeutic, requiring an anesthesia service (ie, general or monitored anesthesia care)
21076	Impression and custom preparation; surgical obturator prosthesis
21079	interim obturator prosthesis
21080	definitive obturator prosthesis
21081	mandibular resection prosthesis
21085	oral surgical splint
21110	Application of interdental fixation device for conditions other than fracture or dislocation, includes removal
21193	Reconstruction of mandibular rami, horizontal, vertical, C, or L osteotomy; without bone graft
21198	Osteotomy, mandible, segmental;
21240	Arthroplasty, temporomandibular joint, with or without autograft (includes obtaining graft)
21242	Arthroplasty, temporomandibular joint, with allograft
21243	Arthroplasty, temporomandibular joint, with prosthetic joint replacement
21255	Reconstruction of zygomatic arch and glenoid fossa with bone and cartilage (includes obtaining autografts)
21440	Closed treatment of mandibular or maxillary alveolar ridge fracture (separate procedure)
21445	Open treatment of mandibular or maxillary alveolar ridge fracture (separate procedure)
21450	Closed treatment of mandibular fracture; without manipulation
21451	with manipulation
21452	Percutaneous treatment of mandibular fracture; with external fixation
21453	Closed treatment of mandibular fracture with interdental fixation
21454	Open treatment of mandibular fracture with external fixation
21461	Open treatment of mandibular fracture; without interdental fixation
21462	with interdental fixation
21465	Open treatment of mandibular condylar fracture
21470	Open treatment of complicated mandibular fracture by multiple surgical approaches including internal fixation, interdental fixation, and/or wiring of dentures or splints
21480	Closed treatment of temporomandibular dislocation; initial or subsequent
21485	complicated (e.g., recurrent requiring intermaxillary fixation or splinting), initial or subsequent
21490	Open treatment of temporomandibular dislocation
21497	Interdental wiring, for condition other than fracture
29800	Arthroscopy, temporomandibular joint, diagnostic, with or without synovial biopsy (separate procedure)
29804	Arthroscopy, temporomandibular joint, surgical
70355	Orthopantogram (eg, panoramic x-ray)
90832 - 90840	Psychotherapy
90901	Biofeedback training by any modality
97010	Application of a modality to 1 or more areas; hot or cold packs
97110	Therapeutic procedure, one or more areas, each 15 minutes; therapeutic exercises to develop strength and endurance, range of motion and flexibility
97124	massage, including effleurage, petrissage and/or tapotement (stroking, compression, percussion)
97140	Manual therapy techniques (e.g., mobilization/manipulation, manual lymphatic drainage, manual traction), one or more regions, each 15 minutes
97530	Therapeutic activities, direct (one-on-one) patient contact by the provider (use of dynamic activities to improve functional performance), each 15 minutes
97810	Acupuncture, 1 or more needles; without electrical stimulation, initial 15 minutes of personal one-on-one contact with the patient
+ 97811	without electrical stimulation, each additional 15 minutes of personal one-on-one contact with the patient, with re-insertion of needle(s) (List separately in addition to primary procedure)
97813	with electrical stimulation, initial 15 minutes of personal one-on-one contact with the patient
+ 97814	with electrical stimulation, each additional 15 minutes of personal one-on-one contact with the patient, with re-insertion of needle(s) (List separately in addition to primary procedure)
CPT codes not covered for indications listed in the CPB:
Bio-oxidative ozone therapy, Magnetic neurostimulator, MIRO therapy - no specific code:
0232T	Injection(s), platelet rich plasma, any site, including image guidance, harvesting and preparation when performed
0481T	Injection(s), autologous white blood cell concentrate (autologous protein solution), any site, including image guidance, harvesting and preparation, when performed
21120 - 21123	Genioplasty
21125 - 21127	Augmentation mandibular body or angle
21141 - 21147	Reconstruction midface, Lefort I
21150 - 21151	Reconstruction midface, Lefort II
21154 - 21155	Reconstruction midface, Lefort III (extracranial), any type, requiring bone grafts (includes obtaining autografts)
21159 - 21160	Reconstruction midface, Lefort III (extra and intracranial) with forehead advancement (e.g., mono bloc), requiring bone grafts (includes obtaining autografts)
21194	Reconstruction of mandibular rami, horizontal, vertical, C, or L osteotomy; with bone graft (includes obtaining graft)
21195 - 21196	Reconstruction of mandibular rami and/or body, sagittal split
21199	Osteotomy, mandible, segmental; with genioglossus advancement
21206	Osteotomy, maxilla, segmental (e.g., Wassmund or Schuchard)
21208 - 21209	Osteoplasty, facial bones
21247	Reconstruction of mandibular condyle with bone and cartilage autografts (includes obtaining grafts) (e.g., for hemifacial microsomia)
21248 - 21249	Reconstruction of mandible or maxilla, endosteal implant (e.g., blade, cylinder)
38205	Blood-derived hematopoietic progenitor cell harvesting for transplantation, per collection; allogeneic
38206	autologous
38230	Bone marrow harvesting for transplantation; allogenic
38232	autologous
38240	Hematopoietic progenitor cell (HPC); allogeneic transplantation per donor
38241	autologous transplantation
38242	Allogeneic lymphocyte infusions
70300	Radiologic examination, teeth; single view
70310	partial examination, less than full mouth
70320	complete, full mouth
70487	Computerized tomography, maxillofacial area; with contrast material(s)
70488	without contrast material, followed by contrast material(s) and further sections
77077	Joint survey, single view, 2 or more joints (specify) [joint vibration analysis for TMJ]
90867	Therapeutic repetitive transcranial magnetic stimulation (TMS) treatment; initial, including cortical mapping, motor threshold determination, delivery and management
90868	subsequent delivery and management, per session
90869	subsequent motor threshold re-determination with delivery and management
90880	Hypnotherapy
95867	Needle electromyography; cranial nerve supplied muscle(s), unilateral
95868	cranial nerve supplied muscles, bilateral
95887	Needle electromyography, non-extremity (cranial nerve supplied or axial) muscle(s) done with nerve conduction, amplitude and latency/velocity study (List separately in addition to code for primary procedure)
95937	Neuromuscular junction testing (repetitive stimulation, paired stimuli), each nerve, any one method
96900	Actinotherapy (ultraviolet light)
96910	Photochemotherapy; tar and ultraviolet B (Goeckerman treatment) or petrolatum and ultraviolet B
96912	Photochemotherapy; psoralens and ultraviolet A (PUVA)
96913	Photochemotherapy (Goeckerman and/or PUVA) for severe photoresponsive dermatoses requiring at least 4-8 hours of care under direct supervision of the physician (includes application of medication and dressings)
97014	Application of a modality to 1 or more areas; electrical stimulation (unattended)
97024	diathermy (e.g., microwave)
97026	infrared
97028	ultraviolet
97032	Application of a modality to one or more areas; electrical stimulation (manual), each 15 minutes
97033	iontophoresis, each 15 minutes
97035	ultrasound, each 15 minutes
97036	Hubbard tank, each 15 minutes
97127	Therapeutic interventions that focus on cognitive function (eg, attention, memory, reasoning, executive function, problem solving, and/or pragmatic functioning) and compensatory strategies to manage the performance of an activity (eg, managing time or schedules, initiating, organizing and sequencing tasks), direct (one-on-one) patient contact
97750	Physical performance test or measurement (e.g., musculoskeletal, functional capacity), with written report, each 15 minutes
Other CPT codes related to the CPB:
70328	Radiologic examination, temporomandibular joint, open and closed mouth; unilateral [covered only when used in conjunction with anticipated surgical management]
70330	bilateral [covered only when used in conjunction with anticipated surgical management]
70332	Temporomandibular joint arthrography, radiological supervision and interpretation
70336	Magnetic resonance (e.g., proton) imaging, temporomandibular joint(s) [covered only when used in conjunction with anticipated surgical management]
70486	Computerized tomography, maxillofacial area; without contrast material [covered only when used in conjunction with anticipated surgical management]
70540	Magnetic resonance (e.g., proton) imaging, orbit, face, and/or neck; without contrast material(s)
70542	with contrast material(s)
70543	without contrast material(s), followed by contrast material(s) and further sequences
HCPCS codes covered if selection criteria are met:
D0320	Temporomandibular joint arthrogram, including injection
D0321	Other temporomandibular joint films, by report
D0322	Tomographic survey
D0340	Cephalometric film
D5931 - D5933, D5936	Obturator prostheses
D5934	Mandibular resection prosthesis with guide flange
D5982	Surgical stent
D5988	Surgical splint
D7630	Mandible, open reduction (teeth immobilized, if present)
D7640	Mandible, closed reduction (teeth immobilized, if present)
D7730	Mandible, open reduction
D7740	Mandible, closed reduction
D7810 - D7880	Reduction of dislocation and management of other temporomandibular joint dysfunctions
D9940	Occlusal guards, by report
D9951 - D9952	Occlusal adjustment, limited/complete
E0746	Electromyography (EMG), biofeedback device
HCPCS codes not covered for indications listed in the CPB:
A4556	Electrodes (e.g., apnea monitor), per pair
A4557	Lead wires (e.g., apnea monitor), per pair
A4558	Conductive gel or paste, for use with electrical device (e.g., TENS, NMES), per oz.
A4595	Electrical stimulator supplies, 2 lead, per month, (e.g., TENS, NMES)
D0350	Oral/facial photographic images
D5110 - D5899	Prosthodontics (removable)
D6210 - D6999	Prosthodontics (fixed)
D7899	Unspecified TMD therapy, by report
D7940	Osteoplasty, for orthognathic deformities
D7941	Osteotomy - mandibular rami
D7943	Osteotomy - mandibular rami with bone graft; includes obtaining the graft
D7944	Osteotomy - segmented or subapical
D7945	Osteotomy, body of mandible
D7946	Lefort I (maxilla, total)
D7947	Lefort I (maxilla, segmented)
D7948	Lefort II or Lefort III (osteoplasty of facial bones for midfce hypoplasia or retrusion), without bone graft
D7949	Lefort II or Lefort III, with bone graft
D7950	Osseous, osteoperiosteal, or cartilage graft of the mandible or maxilla, autogenous or nonautogenous, by report
D7951	Sinus augmentation with bone or bone substitutes
D7953	Bone replacement graft for ridge preservation - per site
D7955	Repair of maxillofacial soft and/or hard tissue defect
E0720	Transcutaneous electrical nerve stimulation (TENS) device, 2 lead, localized stimulation
E0730	Transcutaneous electrical nerve stimulation (TENS) device, 4 or more leads, for multiple nerve stimulation
E0745	Neuromuscular stimulator, electronic shock unit
G0515	Development of cognitive skills to improve attention, memory, problem solving (includes compensatory training), direct (one-on-one) patient contact, each 15 minutes
J0585	Botulinum toxin type A, per unit [Botox]
J0586	Injection, Abobotulinumtoxina, 5 units [Dysport]
J0587	Injection, rimabotulinumtoxinB, 100 units
J0588	Injection, incobotulinumtoxinA, 1 unit [Xeomin]
J7321	Hyaluronan or derivative, Hyalgan or Supartz, for intra-articular injection, per dose [knee only - see selection criteria]
J7323	Hyaluronan or derivative, Euflexxa, for intra-articular injection, per dose [knee only - see selection criteria]
J7324	Hyaluronan or derivative, Orthovisc, for intra-articular injection, per dose [knee only - see selection criteria]
J7325	Hyaluronan or derivative, Synvisc, or Synvisc-One for intra-articular injection, per dose [knee only - see selection criteria]
J9312	Injection, rituximab, 10 mg
ICD-10 codes covered if selection criteria are met:
M26.601 - M26.609	Temporomandibular joint disorder
S02.400+ - S02.413+ S02.42x+ S02.600+ - S02.69x+	Fracture of mandible, closed or open, or malar and maxillary bones closed or open
S03.00x+ - S03.02x+	Dislocation of jaw (closed or open)

The above policy is based on the following references: