Headache and orofacial pain are complaints commonly reported in the same patient, particularly in children and adolescents. In patients with migraine, comorbid temporomandibular dysfunction (TMD) can lead to an increase in migraine frequency and use of migraine medications.
For further insight regarding the diagnosis and management of this patient population, we spoke with Paul G. Mathew, MD, a headache, sports neurology and concussion specialist with Brigham and Women’s Hospital at Harvard Vanguard Medical Associates and Assistant Professor of Neurology at Harvard Medical School in Boston, MA, as well as Steven D. Bender, DDS, the Director of Facial Pain and Sleep Medicine with the Department of Oral and Maxillofacial Surgery at Texas A&M College of Dentistry in Dallas, TX. Both Dr Mathew and Dr Bender uniquely encounter patients with TMD and migraine in their respective practices, and shared their personal experience and advice for managing this often overlooked comorbidity.
How did you first become interested in TMD pathology?
Dr Mathew: First of all, I am married to a dentist, and so I have learned quite a bit about dentistry through my wife, which includes some of the nuances of how dental issues can impact multiple aspects of health and wellbeing. I have also served as faculty for the Tufts Headache and Face Pain Symposium, which brings together dentists and physicians for a highly interactive 2-day program that explores the overlaps between craniofacial pain and orofacial pain.
Over many years of practice, I have treated a growing number of patients who, during a headache history, mention that they also have jaw pain. Unfortunately, after seeking help from general dentists, pain clinicians, and even oromaxillary facial surgeons who may offer invasive surgical procedures, only a small percentage of patients end up being seen by an orofacial pain specialist, a dentist with specialized training in the treatment of disorders including TMD.
Dr Bender: I became interested in TMDs when I was in dental school and then began to study it more earnestly soon after graduation due to my own jaw pain. Also, my wife developed serious TMD pain shortly after I graduated from dental school and I couldn’t find anyone who had the knowledge to help her.
What are the primary mechanisms that can cause both TMD and migraine pain?
Dr Bender: A number of papers describe the incidence of these 2 disorders occurring together, although the mechanisms that may be involved are yet to be fully described. There is thought that convergence of nociceptive information into the trigeminal nucleus caudalis plays a major role in sensitizing the central nervous system (CNS). So, if one has migraine, which is thought to be a disorder where the CNS is more easily sensitized, and you add nociceptive input from other parts of the trigeminal system as seen with TMD, the cascade of events leading to a migraine may be more easily initiated and the patient will experience more frequent and intense migraine events
How do you identify TMD in a patient with migraine?
Dr Mathew: The big issue here is making the diagnosis. Most patients either assume there is nothing that can be done, or they are told by doctors or dentists that they do not treat jaw issues. As such, many patients abandon hope of getting treatment, and may never even seek additional care. In my experience, most patients do not mention this complaint when they present for a headache evaluation, so part of my examination includes evaluating jaw range of motion and palpating the joint, as well as examining the teeth and oral cavity looking for oral pathology. If there are any significant findings, I will ask questions about grinding, clenching, and waking up in the morning with jaw tightness and pain.
Dr Bender: As migraine can sometimes present as a “toothache” or other facial pains, it is important for the provider to be familiar with the diagnostic ICHD 3 criteria of migraine, (ie, a headache that has at least 2 of the following qualities: primarily unilateral, pulsatile, of moderate to severe intensity and/or is aggravated by activity as well during the attack having one of the following: nausea and or vomiting and/or a sensitivity to light and sound, and a duration of the orofacial pain 4-72 hours which then remits) could be indicative of a migraine presentation.1
How important it is to recognize and diagnose TMD?
Dr Mathew: It is very important to make the diagnosis of TMD. If a patient has pain with opening and closing the mouth, it can become very difficult to eat and to talk. In addition, the loud popping and clicking that is often associated with TMD can be socially embarrassing. The human body does not have systems in isolation, so if you have TMD, it can serve as a trigger for migraine. Studies have demonstrated that if you have both migraine and TMD, adequate treatment of TMD can lead to the improvement of the frequency and intensity of migraine. In other words, untreated TMD can make it more difficult to adequately treat migraine.
What diagnostic criteria do you use and why? Do you use any tests to confirm?
Dr Bender: While it’s certainly not perfect, I use the ICHD 3 diagnostic criteria for headache disorders. A new classification for orofacial pains was recently published and may prove useful for standardizing the diagnosis of orofacial pains.2 Also, the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) has been used for some time both in the research arena and clinical practice.3 The DC/TMD also outlines validated examination techniques of the relevant structures involved in temporomandibular disorders.
Ultimately the confirmation will come from the preclinical interview and examination. Additional testing will be directed by the history and examination. New onset headaches and neuropathic pains should usually be imaged with MRI and/or CT, although in most cases, TMDs don’t necessarily require advanced imaging to establish a diagnosis. Laboratory studies are typically not indicated unless the pain presentation is suspected to be a manifestation of a systemic etiology.
Why is a neurological assessment important when a patient has symptoms indicative of TMD?
Dr Bender: A neurologic screening, especially a cranial nerve screening, is an important aspect of an evaluation for most non-odontogenic facial pains like TMDs, neuropathies, neuralgias and headache disorders, particularly if a patient has developed a relatively new onset headache. Conversely, in a neurologic practice, the clinician should become familiar with examination techniques to assess the stomatognathic structures (muscles of mastication, cervical muscles and temporomandibular joints).
What interventions are used to manage these 2 conditions?
Dr Mathew: My first recommendation is that patients see a dentist, preferably an orofacial pain specialist. If they are clenching or grinding, a night guard can be useful. A night guard is a custom-made appliance that can accomplish a few things: 1) Protection of tooth enamel from wear associated with nocturnal clenching/grinding, 2) Prevention of migration of the teeth within the gums and the development of gaps, and 3) Reduction at times of the forces generated from clenching and grinding, which may help reduce tension/pain within the muscles of mastication and the temporomandibular joint.
Second, I advise patients to avoid activities that can exacerbate symptoms, such as chewing very tough things like steak or sticky candy, which can serve as triggers.
Third, a physical therapy referral can be very useful, especially if the therapist is well versed in the management of migraine and TMD. By treating TMD, neighboring muscle groups may benefit. If TMD/neck pain and tightness improve, there is a tendency for migraine frequency and intensity to also improve, so a physical therapist can be very helpful in addressing coexisting posture and ergonomic issues. Most orofacial pain specialists can recommend a local/regional physical therapist who specializes in the management of TMD.
Lastly, I often recommend the use of pharmacological treatments including medications like muscle relaxants and Botox [onabotulinumtoxinA] injections to manage pain from both migraine and TMD.
Dr Bender: Many patients I see have previously consulted with multiple providers for their headaches and TMDs who did not consider the comorbidity of these disorders. I explain to the patient that in most cases, if we can decrease nociceptive information entering the trigeminal system from the stomatognathic structures we will be better able to successfully treat both disorders. With TMDs, we try to start with very conservative measures such as self-care therapies (resting the jaw, ice/heat, limiting certain foods, jaw mobilization techniques and in some cases over the counter analgesics). We may also refer to a physical therapist trained in caring for TMD patients.
In selected cases of refractory masticatory muscle pain, the judicial use of low doses of botulinum toxin may be helpful. The potential benefits of this therapy must be weighed against the risk of osteopenic changes to the involved bony structures.4 Selective nerve blocks and muscle trigger point injections may also be of benefit for some patients.
Pharmacotherapy (muscle relaxers, anti-inflammatories/analgesics) can be beneficial for some patients but in most cases, it is not needed for most TMDs. A custom fabricated intra oral device worn on the teeth (commonly termed an oral splint, night guard or oral orthotic) will benefit many TMD presentations if well designed and constructed specifically for the individual patient’s presentation. More invasive and irreversible therapies such as orthodontics, jaw repositioning procedures, jaw surgeries or bite adjustments should be avoided as these therapies lack evidence and can potentially create even more significant pain. The well-managed TMD patient with a concomitant headache disorder will often find that they require less prophylactic and abortive medications.
Are there other types of therapies (drugs, surgical techniques, patient-applied therapies) that may also help?
Dr Bender: Along with the above therapies, we give the patient self-care instructions to try to decrease sympathetic tone. We will talk to them about behavior modification techniques to stop the habit of awake teeth clenching or bracing. Even light nonfunctional tooth contact has been shown to elicit muscle activity which can add to nociceptive signaling. We also instruct our patients in physical self-regulation based on the work of Carlson et al5 in which patients follow a somewhat structured program designed to decrease sympathetic tone. This will include proper hydration and nutrition, diaphragmatic breathing, posture awareness, adequate sleep, and focused relaxation.
Many pain patients have previously undiagnosed sleep disorders. In our practice, a part of our initial evaluation will include screening for these disorders with questionnaires and the use of home pulse oximetry to screen for sleep related breathing disorders. In many cases, treating the underlying sleep disorder has significantly reduced our patient’s headache and TMD complaints.
A clinical psychologist trained in pain management can also help patients better manage thoughts and behaviors often associated with chronic pain.
How well do pharmacological treatments like Botox work?
Dr Mathew: Oral medications (like muscle relaxants) can be effective, but many patients have difficulty tolerating them. In other cases, patients would prefer not to take a daily oral medications. As such, patients are often quite happy with receiving Botox injections every 3 months, given the convenience and a favorable side effect profile.
Although I have been injecting Botox since 2009, it was FDA approved for the treatment of chronic migraine in 2010. Botox does not have an FDA indication for the treatment of TMD, but I have been injecting for the treatment of this diagnosis since 2013. Securing a Botox prior authorization specifically for the treatment of TMD can be challenging. Nearly all of my Botox patients have a prior authorization for the diagnosis of chronic migraine, and a portion of the Botox units are used for the treatment of TMD.
Botox has an established action of reducing transmission at the neuromuscular junction, which makes it a good option for the treatment of overactive muscles that may play a role in TMD. It also has effects on pain signaling. I was pretty amazed at how, for some patients, injecting 20 units in each temporalis and as little as 5 units in each masseter could significantly improve TMD symptoms. With other patients, I have to gradually increase the dose by 5 units every visit to doses as high as 40 units per side to achieve a benefit. My hypothesis is that lower dose requirements for some patients may reflect the responders who benefit primarily from the effects of Botox on pain signaling, while those requiring higher doses may also need the neuromuscular effect of Botox in order to reduce masticatory hyperactivity. This may explain why patients who are treated in orofacial pain clinics in general tend to need higher doses, as these more refractory cases may have a larger motor component to their TMD.
How often do you treat TMD in patients with migraine?
Dr Bender: As an orofacial pain specialist, the majority of my practice consists of diagnosing and managing people with TMDs. So, I probably see 6-8 patients per day with some form of a TMD.
Dr Mathew: I encounter patients with TMD every single day in clinic, multiple times a day. I would say that if I am performing Botox injections on 15 patients for the treatment of chronic migraine in a day, at least 5 of them are receiving masseter injections for treatment of TMD. TMD is extremely common in my headache medicine practice because I am actively looking for it through my history-taking and examination. If clinicians are overlooking TMD signs and symptoms, the diagnosis will not be made, and an opportunity to treat will be lost.
What outcomes can be expected for comorbid TMD/migraine?
Dr Bender: While every individual will have a unique presentation, if the clinician engages in a comprehensive examination process beyond the traditional neurologic examination and employs evidenced-based therapies for both disorders, outcomes can be very predictable and successful. These therapies are often more comprehensive than the pharmacotherapeutic-based approaches employed by most headache practitioners. Many of our patient’s with TMDs note a significant improvement in their headache intensity and frequency when their TMD is well-treated.
Dr Mathew: I find the best results occur when patients are on combination treatment with an oral appliance, trigger avoidance, physical therapy with continued self-guided home stretching/exercises, and pharmacological treatment. This is where interdisciplinary collaboration between the neurologist/headache specialist, dentist/orofacial pain specialist, and physical therapist can lead to the best outcomes.
1. Headache Classification Committee of the International Headache Society (IHS). The International Classification of Headache Disorders, 3rd edition. Cephalagia. dio: 10.1177/0333102417738202
2. The Orofacial Pain Classification Committee. International Classification of Orofacial Pain. Cephalagia. doi: 10.1177/0333102419893823
3. Schiffman E, Ohrbach R, Truelove E, et al. Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) for Clinical and Research Applications: recommendations of the International RDC/TMD Consortium Network and Orofacial Pain Special Interest Group. J Oral Facial Pain Headache. doi:10.11607/jop.1151
4. Kahn A, Kün-Darbois JD, Bertin H, Corre P, Chappard D. Mandibular bone effects of botulinum toxin injections in masticatory muscles in adult. Oral Surg Oral Med Oral Pathol Oral Radiol. 2020;129:100-108. doi: 10.1016/j.oooo.2019.03.007. Abstract.
5. Carlson CR, Bertrand PM, Ehrlich AD, Maxwell AW, Burton RG. Physical self-regulation training for the management of temporomandibular disorders. J Orofac Pain. 2001 Winter;15:47-55. Abstract.
This article originally appeared on Neurology Advisor