Does anyone really know the cause or how to diagnose Burning Mouth Syndrome?
Ross Hauser, MD
In this article, we will explore the possibility that some people with Burning Mouth Syndrome may have its cause in cervical spine instability causing compression on the vagus nerve, the facial nerve, and the glossopharyngeal nerve, and problems of cerebral blood flow. This would then create an altered sensation (burning) into the tongue and mouth.
If your tongue feels like it is on fire yet all your tests come back negative, you have probably been diagnosed with burning mouth syndrome (BMS). If we took the combined emails we received about problems of Burning Mouth Syndrome, a common thread would create a cumulative person’s that would go something like this:
My mouth and tongue feel like they have been burnt, like from a hot spoon or scolding coffee. I went to the dentist to see if this was a problem with my gums or an infection in my teeth. None of the x-rays showed anything. He told me that he thought it was Burning Mouth Syndrome. Nothing could be done for it except anti-depressants. When I went to my doctor, I was referred to a specialist, a Psychiatrist.
I have had years of treatments including Botulinum toxin. It is not just Burning Mouth Syndrome but I also have double vision, neck pain, issues with swallowing, and nonstop pain. My doctors think I am crazy and will not listen to me.
A more complicated situation
We will see a more complicated situation in which burning mouth syndrome is part of a myriad of challenges and problems the person is facing. This is more typical of the person we see at our center. In this scenario the person will be:
- Initially diagnosed with burning mouth syndrome a few years prior.
- Was seeing many doctors because they were having a lot of symptoms. The problems of burning mouth syndrome being one group of symptoms.
- As their examination continued they will receive more diagnoses. These may include Trigeminal neuralgia or Cervicogenic headaches: Migraines, and tension headaches.
- Because of continued pain in their neck, they will have an MRI which will demonstrate a problem with cervical degenerative disc disease.
- Following these examinations and newly discovered diagnoses a conservative treatment plan will be offered:
- For headaches, medications, or a botulinum toxin injection.
- For the symptoms of burning mouth, medications, and possibly a “nerve burning.”
- Sometimes these treatments will help, sometimes they will not. Sometimes there is inconsistency as some days are tolerable and some days the burning and other symptoms are really bad. For this person, none of the treatments they are getting can be absolutely pinpointed as being helpful or not. So as for medications, they take them all.
- Ultimately their neurologists will recommend them to an orthopedist for their neck and perhaps a neurological dentist for their mouth. For this person, this now means surgery on top of everything else they have endured and a promise of more doctors, more specialists, more physical therapists, more medicine.
- Sometimes these people will be sent off to psychiatric assessment.
Sometimes a surgery can cause Burning Mouth Syndrome
This is an email we received, it has been edited for clarity.
I was diagnosed with burning mouth syndrome several years ago. Following the diagnosis, as time went on, I didn’t even really know I had it. As symptoms began to redevelop, my doctor recommended Microvascular decompression. During the surgery, my glossopharyngeal nerve was cut and a Polyvinyl Alcohol Sponge was placed next to the vagus nerve to help during the surgery. Following the surgery my burning mouth syndrome came back with a vengeance. Not only is the burning bad but I keep tasting whatever it was I last ate. This happens after anything I eat. I get a horrible sour taste that won’t go away. Can’t get any of the doctors to listen.
Does anyone really know the cause or how to diagnose Burning Mouth Syndrome
The difficulty in understanding burning mouth syndrome is seen in an August 2022 paper published by German researchers quested with finding a dermotologic cause. (11)
“Glossodynia or orofacial pain disorder is known as burning mouth syndrome. It is a therapeutic challenge. Its etiology is not well defined. Recent studies show not only a correlation with neuropathic changes, but there are also indications of comorbidities such as depression, anxiety, and carcinophobia (a fear of getting cancer). These (previous symptoms) can also manifest as a reaction to the disease and are not necessarily considered causative. (In other words neuropathic changes, depression, and anxiety are not considered the causes). Burning mouth syndrome poses a diagnostic challenge since its differential diagnosis is broad. With regard to dermatological aspects, lichen planus mucosae (chronic inflammatory skin disorder), oral leukoplakia (white lesions in the mouth normally associated with alcohol and tobacco use) pemphigus vulgaris (an immune disorder attacking the skin inside the mouth), and aphthous mouth ulcers should be considered. Diabetes, anemia, vitamin deficiency, and endocrinological influences should be considered regarding the predominance of elderly and female patients. Meta-analyses of treatment studies usually show a low level of evidence of the randomized, controlled trials. According to the literature mainly psychotherapy and antidepressants are proposed for therapy. Alpha lipoic acid as a dietary supplement shows short-term improvement and low-level laser therapy might have some benefit.”
The difficulty doctors face in understanding what Burning Mouth Syndrome is and how to treat it
Research published in the Journal of Headache and Pain (2) describes the difficulty doctors face in understanding what Burning Mouth Syndrome is and how to treat it.
Here are some of the bullet points of this study, parenthesis are added for emphasis and understanding.
- Burning Mouth Syndrome is a chronic pain condition characterized by persistent intra-oral burning without related objective findings (no reason) and unknown etiology (We can’t figure out where it comes from) that affects elderly females mostly.
- There is no satisfactory treatment for burning mouth syndrome. (This should be pointed out that this refers to traditional treatments including anti-depressants and pain medications).
- (The researchers) aimed to observe the long-term effects of high venlafaxine doses (Anti-depressant nerve medication that can be prescribed for generalized anxiety disorder, panic disorder, and social anxiety disorder), combined with systemic and topical administered clonazepam (a sedative for seizures, panic disorder, and anxiety. Side-effects include suicidal thoughts and paranoia), in a particular subgroup of burning mouth syndrome patients who do not respond to current clinical management.
- Conclusion: “Refractory burning mouth syndrome deserves bottomless psychiatric evaluation and management when currently available treatments fail. Paraclinical investigation including brain imaging and peripheral facial nerve conduction evaluation may be needed.”
Is Burning Mouth Syndrome a problem for elderly people who must have psychiatric problems because there is no other explanation?
I want to point out that we see many patients with Burning Mouth Syndrome. However much of the research in the medical community suggests that this is a problem most elder patients with no real understanding of what is happening in the patient and without understanding there must be anxiety, panic, and depression, and perhaps treating these problems will help the patient’s quality of life.
A 2019 study in the journal BioPsychoSocial Medicine (3) from the Department of Psychosomatic Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University offers us these observations and suggestions:
“Burning Mouth Syndrome, a chronic intraoral burning sensation or dysesthesia without clinically evident causes, is one of the most common medically unexplained oral symptoms/syndromes.
Even though the clinical features of Burning Mouth Syndrome have been astonishingly common and consistent throughout the world for hundreds of years, Burning Mouth Syndrome remains an enigma and has evolved to a more intractable condition.
In fact, there is a large and growing number of elderly Burning Mouth Syndrome patients for whom the disease is accompanied by systemic diseases, in addition to aging physical change, which makes the diagnosis and treatment of Burning Mouth Syndrome more difficult.
Because the biggest barrier preventing us from finding the core pathophysiology and best therapy for Burning Mouth Syndrome seems to be its heterogeneity (the fact that it can be caused by many things and the difficulty of finding the true source is obvious) this syndrome remains challenging for clinicians.”
So to treat this problem, this study reviews the current treatment guidelines for:
- Central neuromodulators (Tricyclic Antidepressants – TCAs, Serotonin, and Norepinephrine Reuptake Inhibitors – SNRIs, Selective Serotonin Reuptake Inhibitors – SSRIs, Clonazepam) and solutions for applying non-pharmacology approaches.
- Cognitive-behavioral therapy:
- The researchers suggested that while pain severity and discomfort of Burning Mouth Syndrome were improved by Cognitive behavioral therapy targeting cognitive factors, positive outcomes may only be realized for six to twelve months and that many sessions (12-16) were needed to complete a Cognitive behavioral therapy course. In our observations, we note that cognitive-behavioral therapy can be successful for some, for others this is another treatment that relies on symptoms suppression and not a treatment that seeks to treat the actual cause of the Burning Mouth Syndrome.
Patients stopped taking their psychotropic medications
- The researchers noted that while psychotropic medications are effective in the treatment of BMS, a high frequency of non-adherence was found in a population study of psychotropic medications
- In Burning Mouth Syndrome, about 15% of the patients stop taking psychotropic medications.
BMS involves severe pain in the tongue and oral muscosal surfaces of the mouth.
A September 2022 paper in the Journal of oral rehabilitation (12) suggests understanding the disease from a patient’s perspective “should be considered in accordance with a biopsychosocial model.” In other words, not just one thing. In a a biopsychosocial model, the patients heath condition, social environment (factors impacting them within society such as job stress) and psychological factors including mood disorders, sleep and quality of life. What these researchers found was that from a patient’s perspective, pain caused by Burning Mouth Syndrome as a key component and that this was not well understood by doctors using standard testing. The researchers concluded “Pain tests are differently correlated with mood and quality of life. Therefore, a complete analysis of the patient requires several tools to better understand the multidimensional aspects of pain in Burning Mouth Syndrome.”
Burning Mouth Syndrome involves severe pain in the tongue and oral muscosal surfaces of the mouth. It typically gets worse the more a person talks. Other symptoms include an itching sensation, numbness, taste alteration (bitter/acid/spicy or metallic taste), dry mouth, burning pain or oral stinging pain. These symptoms are almost always located in the tongue or oral mucous membranes and in more than one oral site, with the anterior two thirds of the tongue, the anterior hard palate and the muscosa of the lower lip most frequently involved. This symptoms were described and alluded to in a 2016 paper published in the medical journal BMJ clinical evidence.(1) This paper is cited by the 2022 researcher listed just above.
Pertinent to burning mouth syndrome, the lingual branch of the mandibular nerve (a branch of trigeminal nerve) supplies the anterior two-thirds of the tongue with sensation. Some of the sensory information from the trigeminal nerve and the upper cervical spine converge to the same region in the cervical spinal cord called the trigeminocervical nucleus. What this means is that any type of injury in the area of the trigeminal nerve or C0-C3 spine can give burning pain in the mouth. Typically patients with BMS have an injury to the TMJ or upper cervical vertebrae or both. It is important to understand that the C2-C3 zygapophysial joint is the most implicated pain generator, and the atlantoaxial joint is the second most commonly implicated joint for the head and neck pain that often occurs with cervicogenic headaches.
Burning mouth a psychiatric problem?
But is Burning Mouth Syndrome a psychiatric problem? In the research below some doctors will consider it so because some patients will have some type of symptom alleviation with psychiatric drug prescription.
Fortunately, some people diagnosed with Burning Mouth Syndrome do get benefits from anti-depressants. We see some of these patients as they continue to seek other options. We also see the people for whom anti-depressants did not provide relief. They are looking for something that may help them.
Why anti-depressants? Anti-depressants can help with nerve pain. They are also seen as a way to “buy time.” People who believe that their problems were related to root canals or extensive dental work are typically given drugs such as Amitriptyline or Velanfaxine and given the hope that this will hold them over until the pain goes away by itself. Again, I want to point out that this article will focus on the nerves that run into the cervical spine as a cause of the person’s Burning Mouth Syndrome. Anti-depressants may be offered when someone is diagnosed with idiopathic Burning Mouth Syndrome. Idiopathic meaning no known cause. As we will discuss in this article, one unknown or undiagnosed cause may be with the sensory nerves.
Burning mouth a stress and physical activity problem?
An October 2020 study (4) suggests that stress and physical activity may be factors in Burning Mouth Syndrome. Here is what they wrote:
“Burning mouth syndrome is a long-lasting pain condition which is commonly associated with anxiety symptoms and experience of adverse, stressful life events have been reported by those diagnosed with the syndrome. Stress-related biomarkers (Enzymes, such as alpha-amylase and lysozyme) have been related to personality traits in Burning mouth syndrome and a personality with high-stress susceptibility and perceived stress may be of importance.”
To test this idea the researchers investigated if personality, perceived stress, and physical activity distinguish women with Burning mouth syndrome from women who did not have burning mouth syndrome.
Of course, the women with Burning mouth syndrome are going to have more stress
Before we get to the results of this study, you probably are saying to yourself, “Of course the women with Burning mouth syndrome are going to have more stress, I have Burning mouth syndrome and I have a lot of stress.” What we are looking for in this study is what would help this stress. Here is what the researchers suggested:
“Perceived stress was higher and weekly physical activity was lower in women with Burning mouth syndrome compared to controls. Our findings suggest physical activity should be more comprehensively measured in future Burning mouth syndrome studies and, by extension, physical activity may be a treatment option for women with Burning mouth syndrome. Pain management aiming to restore function and mobility with stress reduction should be considered in clinical decision making for women with Burning mouth syndrome who have a personality with stress susceptibility, especially if reporting high perceived stress and insufficient physical activity.”
How do you get women with Burning Mouth Syndrome more physical activity?
The question is then, how do you get women with Burning mouth syndrome more physical activity? You remove pain with pain management so that these women can move better. In this article, we will discuss the cervical neck pain element of Burning mouth syndrome. Restoring correct cervical spine curves and motion are key elements of our treatments.
Is Burning Mouth Syndrome caused by migraines?
An April 2022 paper (13) aimed to identify the association of migraine with the risk of developing Burning Mouth Syndrome. The study suggested that “migraine are associated with an increased incidence of Burning Mouth Syndrome. Therefore, clinicians should be attentive to detect Burning Mouth Syndrome at an early stage when treating patients with migraine.”
Does anything help Burning Mouth Syndrome?
Recently, doctors and dentists in the United Kingdom released a detailed examination of the conventional treatments available to patients with burning mouth syndrome. (5)
Here is the summary of their findings:
The treatments examined were the usual treatments we have discussed above in other research.
- antidepressants and antipsychotics,
- dietary supplements,
- electromagnetic radiation,
- physical barriers,
- psychological therapies,
- and topical treatments, including capsaicin oral rinse.
They concluded in this group of treatments “evidence for effectiveness was very low for all interventions and all outcomes.”
Many, like you, have many health problems that may be attributed to Burning Mouth Syndrome
Similar to what we see in patients in our clinic are symptoms and health problems noted by researchers in the medical journal Oral Diseases. (6) A research group from the School of Dentistry, Complutense University, Madrid, Spain made these observations:
“The relationship of Burning Mouth Syndrome with possible alterations in patients’ general health has been the subject of study and controversy during the last years.”
In this paper, the researchers conducted a case-control study to compare the diseases, medications, blood test alterations, disturbances in general health, oral quality of life, xerostomia (dry mouth), sleep quality, and psychological status between a group of 20 patients with burning mouth syndrome and a group of 40 patients who did not suffer from this disease.
- Burning mouth syndrome patients suffered more comorbidities and consumed more medications than controls. More mental, behavioral or neurodevelopmental disorders in burning mouth syndrome patients were found, consuming more drugs for nervous and cardiovascular systems, and alimentary tract and metabolism.
Burning mouth a nerve problem or a dental problem? Is it a problem of a root canal?
Often we will be contacted by someone who had their Burning Mouth Syndrome made worse or develop from a root canal. The root canal may have been an event to trigger the symptoms but in many people who contact us they report a history of neck pain and involuntary movement or spasm.
Others tell us that after their diagnosis of Burning Mouth Syndrome all that could be done was to make a soft plastic dental guard for the roof of their mouth and be given prescriptions for Klonopin (Clonazepam). The Klonopin prescription coming after a health care provider confessed that they do not know what is causing the person’s Burning Mouth Syndrome.
In the above study, it is suggested that peripheral facial nerve conduction evaluation may be needed. This may point to our suggestion that in some patients burning mouth syndrome may be caused by nerve dysfunction.
A March 2020 study in the Journal of Oral Science (7) comes from the Nihon University School of Dentistry in Japan. Again this is a school of dentistry research paper looking for an answer to burning mouth syndrome. Let’s listen to what they are saying.
“Burning mouth syndrome is one of the most frequently seen idiopathic pain (again this is a pain that comes on suddenly without any reason), conditions in a dental setting. Peri- and postmenopausal women are most frequently affected, and patients who experience burning mouth syndrome complain of persistent burning pain mainly at the tip and the bilateral border of the tongue.
Recent studies have assessed whether burning mouth syndrome is a neuropathic pain condition. (Note: This was based on varying factors including abnormal pain responses (or exaggerated pain response), where the patient is having more pain than they should. I want to point out that the patients do suffer from more pain than they should and it is not a psychiatric disorder).
“Somatosensory studies have reported some abnormal findings in sensory and pain detection thresholds with inconsistency; however, the most distinct finding was exaggerated responses to painful stimuli. Imaging and electrophysiologic studies have suggested the possibility of dysregulation of the pain-modulating system in the central nervous system, which may explain the enhanced pain responses despite the lack of typical responses toward quantitative sensory tests.”
This also may point to our suggestion that in some patients, burning mouth syndrome may be caused by nerve dysfunction.
I was a successful career person, active, teenage kids, then neck pain turned into Burning Mouth Syndrome and my life upside down.
Every story we hear is unique to that person. However, because of conventional treatment guidelines offered to these people by their doctors, they almost all, for the most part, wander down a similar path and medical journey. In many, we hear the story of a woman in her 40s or early 50s. They are successful career women and equally successful in the family.
Their path down the medical rabbit hole started with a nagging neck pain that eventually continued to more significant neck pain and then the development of neurologic-like and psychiatric-type symptoms.
In cases of mouth pain or weird sensation, this person would start to notice tingling sensations in their mouth, neck and perhaps radiating out into their arms. Because this was a successful career woman, many times their strange sensations would be simply attributed to “stress of the job,” and the treatment was “you should take a vacation.” Many times they did take a vacation but the symptoms persisted and now they are attracting the attention of their doctors who send them through the conservative treatment guidelines already outlined above. Underlying all this is that their doctors have not found an underlying reason for their problems.
Seeking a “cure” or alleviation from their problems this person may go one to include physical therapy, yoga, and exercise or chiropractic care. Sometimes a visit to the chiropractor would identify upper cervical spine instability and help the person understand their problem, sometimes maladjustment would send the person spiraling into a new set of symptoms. Often we will hear that after one adjustment, headaches, vertigo, loss of balance would overcome them, and the only way to stop these symptoms was to keep their head in a certain position. A neck collar would be given to them or for many they would go online and buy one on their own.
Over the course of time, the symptoms of Burning Mouth Syndrome would develop.
Is Burning Mouth Syndrome a problem of cerebral blood flow and altered gray matter?
At the onset of this article, I wrote of the possibility that some people with Burning Mouth Syndrome may have its cause in cervical spine instability causing compression on the vagus nerve, the facial nerve, and the glossopharyngeal nerve, and problems of cerebral blood flow. This would then create an altered sensation (burning) into the tongue and mouth. Below I am going to utilize some of our illustrations to help lay the groundwork for the research that I will present and then we will look at my video presentations of a case study of a patient with cervical spine instability causing the major symptom of Burning Mouth Syndrome.
What are we seeing in this image? The C1, C2, C3 nerve roots and how they wander through and around the bones of the cervical spine.
In research and clinical observation, we will discuss how compression of the C1, C2, C3, nerve roots can lead to the problem of Burning Mouth Syndrome. When the bones of the neck are unstable, they wander around banging into other important nerves and blood vessels. How do these bones become unstable? How does cervical instability develop? An injury or wear and tear of the cervical spinal ligaments, the dense connective tissue that holds the bones in place. Without these bands holding the C1, C2, C3 vertebrae in place not only do the bones compress and bang into the blood vessels and other nerves, but they stretch out the C1, C2, C3, nerve roots causing a delay or disruption of messages between the brain and the movement of the head. So here we have the very nerve roots whose primary job is to move the head up and down and side to side sending distorted messages back and forth to the brain.
The key is distorted messages. If the nerves are not communicating correctly, symptomology can develop including Burning Mouth Syndrome. This is explained in greater depth below.
What are we seeing in this image? The neurology and vascularity of the cervical spine and how compression from cervical instability can cause symptomology including Burning Mouth Syndrome
The main purpose of the illustration is to show the various nerve and vascular structures in the neck and their close proximity and relationship to each other. In this illustration, we see the
The Superior Cervical Ganglion
The Superior Cervical Ganglion or the superior cervical sympathetic ganglion is part of our flight-fight response and a key component of our messaging network that sends crucial instructions through the body. The uniqueness of the superior cervical sympathetic ganglion is that it is the only ganglion (in simplest terms a nerve station that relays nerve messages) that innervates the head, neck, and innervates portions of the face. So clearly we can see how dysfunction of the superior cervical sympathetic ganglion can send bad messages that can lead to a burning mouth sensation. Further, the superior cervical ganglia need blood from the ascending pharyngeal artery and drainage from the internal jugular vein to function correctly. If a wandering C2 or C3 bone is compressing these blood vessels the superior cervical ganglia can also send distorted messages into the face and mouth causing symptomology.
Let’s back this up with some research.
A 2017 paper in the journal Brain and Behavior (7) made these observations on the superior cervical sympathetic ganglion and its interconnected nerves and blood vessels.
“Cervical nerves contain many sympathetic nerves after leaving the superior cervical sympathetic ganglion that connects to head and neck muscles, the carotid bifurcation (where the carotid artery splits into two), the sympathetic ganglion of the salivary gland, the common carotid artery, the internal vein, and connective tissue.
The communication between the vagus nerve and cervical sympathetic ganglion may affect the blood flow of the carotid artery and hoarseness related to the recurrent laryngeal nerve.”
See the connection to a possibility of neurological-like problems causing Burning Mouth Syndrome?
There is something wrong with my spit
Here is one more consideration point. Above is a mention of the impact on the salivary gland. We are going to refer to a 2002 (8) study published in the journal Oral medicine for a better understanding of the role of saliva in Burning Mouth Syndrome
“Stomatodynia (pain in the mouth) is the complaint of burning, tickling, or itching of the oral cavity, and can be associated with other oral and non-oral signs and symptoms. However, the oral mucosa often appears normal, with no apparent underlying organic cause to account for the symptomatology.
The etiology is unknown, though evidence points to the participation of numerous local, systemic, and psychological factors. Among the local factors, saliva may play an important role in the symptoms of burning mouth.
Saliva possesses specific rheological (the flow of saliva) properties as a result of its chemical, physical and biological characteristics – these properties being essential for maintaining balanced conditions within the oral cavity.
Patients with burning mouth present evidence of changes in salivary composition and flow, as well as a probable alteration in the oral mucosal sensory perception (simply your brain may be getting messages that you have dry mouth but you do not) related particularly to dry mouth and taste alterations.”
What are we seeing in this image?
The caption reads:
The cervical sympathetic and the continuation of autonomic fibers to effectors in the head. Simply, In the autonomic nervous system, nerve fibers or preganglionic fibers, connect the central nervous system to the nerve ganglia. It is a communication highway from brain to body.
In the illustration we ask you to note the relationship of the superior cervical ganglion to the Vagus and glossopharyngeal cranial nerves and the internal carotid artery. This is because of the various communications between these structures. More importantly and as attested to by research already cited above (7) “The communication branches of the superior cervical ganglion are mainly connected to the vagus and glossopharyngeal nerves.”
We also asked you to pay attention to the Gray (not white) rami communicates course from the cervical chain to the cervical spinal nerves. Understanding your Burning Mouth Syndrome may lie in an understanding of nerve impulses. The grey and white rami communicantes are as they are described. They communicate nerve impulses. They are colorized by the amount of myelinated nerve fibers. Myelinated (simply insulated with fat) nerve fibers contain a myelin insulation. There are more more myelinated than unmyelinated fibres in the white rami communicantes while the opposite is true for the grey rami communicantes. What does that mean? White impulses move faster the gray impulses because of the myelinated (better communication insulated by the fatty sheath). Why were you built this way? The Gray rami simply moves up and down the spine conveying messages. Once the spine wants to send a message to the brain the impulse moves over from gray to white rami. It is at this point, because the brain needs messages to be delivered as fast as possible, that the impulse will then travel the white faster route.
The problem is, the messages coming from the gray rami communicates. Since it does not have the insulation, these messages can be distorted or corrupted.
What are we seeing in this image? The C1-C2-C3 nerve roots connecting with the Hypoglossal nerve going into the mouth
Many people with Burning Mouth Syndrome may have issues with speech or tongue movements. That is part of their symptomology. Here is how compression of the C1, C2, C3 impact these symptoms as well as lead to the Burning Mouth Syndrome problem.
A connection between brain drainage, cerebral blood flow, and Burning Mouth Syndrome
“A change in gray matter volume and cerebral blood flow in patients with burning mouth syndrome”
What are we seeing in this image? A suggestion that cervical spine instability can cause blockage of the cerebrospinal fluid (CSF) and this, in turn, can cause a change in the gray matter of the brain and in turn cause Burning Mouth Syndrome. What is common with the evidence I presented above putting a focus on C1, C2, C3 instability causing dysfunction in the local nerve roots and bundles, here a cut off the drainage of the brain leads to a loss of gray matter. Research has made a connection between this loss of gray matter and the development of Burning Mouth Syndrome.
In this illustration below, the problem starts with cervical ligament damage at C1-C2 causing cervical spinal fluid flow blockage.
What are we seeing in this image?
A cervical venous system that allows the brain to drain.
As demonstrated in this image, the brain drains primarily via the internal jugular and vertebral venous plexus. Over the many years of helping people with cervical spine problems, we have come across a myriad of symptoms that seemingly go beyond the orthopedic, musculoskeletal, and neuropathic pain problems commonly associated with cervical spine disorders, “herniated disc,’ and cervical radiculopathy. While many patients can understand that cervical neck instability can cause problems with pinched nerves and pain and numbness that can extend down into the hands or even into the feet, they can have a lesser understanding that their cervical spine instability also pinches on arteries and the veins in the neck and disrupts, impedes and retards blood flow into the brain and the drainage of this blood and other fluids that can cause intracranial pressure and the symptoms we described above and those we will describe below.
In April 2019, researchers published a paper titled: “Change in gray matter volume and cerebral blood flow in patients with burning mouth syndrome.”(9) What was the message of this paper?
The researchers evaluated alterations in gray matter volume and cerebral blood flow in the brain in patients with Burning Mouth Syndrome. What they found was the gray matter volume was smaller in the left thalamus (the part of the brain that relays motor and sensory signals to the cerebral cortex (simply the main body of the brain)) and left middle temporal gyrus (areas that control memory, vision, cognitive function) in the Burning Mouth Syndrome group when compared to controls. What they also noticed was regional cerebral blood flow in the Burning Mouth Syndrome group was significantly decreased in the left middle temporal gyrus, left insula, right middle temporal gyrus, and right insula compared with controls. Let’s point out that the insulas are parts of the brain recently implicated as being a lead in the triggering of our sensation of pain. In Burning Mouth Syndrome patients, there was a significant correlation between gray matter volume and pain severity in the left middle temporal gyrus.
The conclusion was: “The reduced gray matter volume seen in the thalami of BMS patients is consistent with the pattern observed in those with chronic pain disease, which implies that the pathogenesis of BMS may be associated with atrophy of the brain structures associated with thalamocortical processing. In addition, changes in CBF in the insula and middle temporal gyrus were also observed.”
A Patient’s Case History – Burning Mouth Syndrome
- The patient is a young mother with horrible symptoms of burning mouth, the top of the roof of her mouth is burning, the tongue is burning, the back of the throat is burning,
- She has had these symptoms for two years.
- The patient has seen many physicians, dentists, ENT specialists, and no one has had any success at relieving the terrible burning sensation.
Dr. Hauser at 1:00 of the video:
Why I believe burning mouth syndrome is from cervical instability, specifically upper cervical instability
- I think after I present this case you will understand why I believe burning mouth syndrome is from cervical instability, specifically upper cervical instability.
- This case is always going to illustrate why most unusual neurological conditions are from cervical instability for instance if a person had brain fog or they had tachycardia of the heart that would come and go they have some unusual symptom that no one can seem to resolve what I would encourage you to ask yourself is could this be a cervical instability issue.
- In this particular patient when you actually question her further she has all the signs and symptoms of a cervical instability case:
- she has horrible dizziness,
- she has poor balance,
- she has terrible digestive problems where she has constipation and diarrhea,
- she has floaters in her eyes, her vision has some issues,
- she gets a migraine headache when she subjected to a lot of light because her pupils can not constrict,
- she has trouble swallowing, like when she eats dry food it gets stuck in her throat,
- she sounds like somebody who is three pack a day smoker as she is very hoarse.
- she has ear fullness.
The patient was an amazing athlete, she met her husband and fell in love with him in college where they both excelled in sports, now she’s very disabled. Her chiropractor thought that her problem was upper cervical instability so that’s why she came to Caring Medical Florida. But her myriad of symptoms suggest that she has irritation of her vagus nerve because all of these symptoms can be because the vagus nerve is not functioning properly, is not giving the right input to the brain, and some of the impulses through the vagus nerve are not getting through.
The patient’s Digital Motion X-Ray reveals possible symptom causes and a syrinx at C5 is examined
This segment of the video begins at 3:30
I think you’ll find her digital motion x-ray very fascinating but before I even talk about that, what is also unusual about her case is when I was reviewing for medical history, she, had an MRI from a while ago that showed us that she had a syrinx from C5 to the mid-thoracic area. So she actually has a fluid-filled sac in her spinal cord (the syrinx) and it starts at C5. So it will be interesting in reviewing her digital motion x-ray if she has instability right above where the syrinx.
At 4:09 loss of the cervical curve
With our face-down lifestyle, a lot of people are getting cervical ligament laxity and what that causes is a loss of the cervical curve that’s what we see in this particular patient we even see that the ligaments in her neck can’t even keep the vertebrae together even at rest.
At 4:34 of the video, Dr. Hauser discusses the patient’s problem with cervical spine instability.
- The C1 vertebra is a little bit tilted
- At C2/C3 the vertebrae are offset (misaligned) so we know this particular person is gonna have severe instability at C2-C3.
- There is also an offset at C3-C4 and an offset at C4-C5. Even before we ask the patient to do certain movements while under the DMX, we know that this particular person is going to have a significant ligament injury in these areas.
- This person also is very loose-jointed and I believe that anybody who has chronic pain and they have extra flexibility throughout their body that more likely than not the cause of their chronic pain is going to be ligament injury.
Neck movement observed under DMX at 5:30
- At C4/C5 – We can see how much instability there is at C4-C5. As noted this patient has a syrinx at C5. This type of instability in the neck can block cerebral spinal fluid flow. In this patient’s case here the cerebral spinal fluid flow is getting blocked in C4-C5 and I believe that’s the cause of her syrinx. The syrinx, the fluid-filled sac in the spinal cord is not the cause of her burning mouth.
- At 6:29 of the video, the DMX open mouth views demonstrate a significant instability at C1-C2 from cervical capsular ligament laxity.
- Treatment discussion at 7:05. By her third Prolotherapy treatment session, her burning mouth symptoms started to go down. Some people come in with such severe instability it may take 2 or 3 or 4 visits just to get them from the severe stage of instability to a moderate amount of instability. In this patient, the prognosis is excellent to get complete relief not just of her burning mouth symptoms but also all the other vagus nerve symptoms that she has, such as a change in her voice quality, hoarseness, difficulty swallowing, digestive complaints, eye complaints, the ear fullness that she has. So, she’s excited and we’re excited to treat her.
In this video Ross Hauser, MD discusses the problem of Burning Mouth Syndrome and how disruption of the Cranial Nerves, specifically the Vagus Nerve can cause Burning Mouth Syndrome.
A transcript summary and explanation notes are added below.
I remember the first case of burning mouth syndrome I treated, it was about 25 years ago. This patient thought the problem was their teeth, they had a lot of dental work thinking that would rid them of the burning mouth problem they had.
- Following the dental work’s failed pain alleviation, the patient then sought out alternative holistic medicine providers. Here they were suggested to gluten-free and dairy-free diets along with herbal supplementation. They were told to avoid spicy foods, hot foods, and beverages, or other foods that may cause them discomfort.
Chiropractor diagnoses patients with upper cervical instability
- When the alternative holistic medicine failed, they sought out care from a chiropractor. The chiropractor felt that the problem was upper cervical instability. The problem of their burning mouth was coming from the neck. That chiropractor did this patient a big favor. This patient came to me, received Prolotherapy treatments, and responded very well. As will be explained below Prolotherapy is a series of simple dextrose injections into the cervical spine. The goal of the treatment is to strengthen the cervical spine ligaments and provide stability and a return to the normal cervical spine curve. This will help relieve the possible pressures the vertebrae are causing on the nerves that lead into the mouth, tongue, and face.
The nerves that lead into the mouth, tongue, and face
A study from New York University School of Medicine/Langone Medical Center (10) describes the interaction of the facial nerve (seventh cranial nerve CN VII), the glossopharyngeal nerve (ninth cranial nerve CN IX), and the vagus nerve (tenth cranial nerve CN X) and symptoms of burning mouth syndrome.
“Alterations in taste and quantity of salivation are commonly reported in burning mouth syndrome. The chorda tympani branch of the facial nerve (CN VII) supplies chemoreceptors for taste in the anterior (front) two-thirds of the tongue. The glossopharyngeal nerve (CN IX) provides taste sensation for the posterior (back) third of the tongue. There are also taste receptors on the soft palate supplied by the greater superficial petrosal nerve branch of the facial nerve and on the larynx from the superior laryngeal nerve of the vagus nerve (CN X).”
- Dr. Hauser in the video: The vagus nerve runs right along the anterior border (the front) of the C1-C2 vertebrae, down into the neck and it makes its way to the digestive tract. The cause of burning mouth syndrome can be attributed in some cases to compression or stretching of the vagus nerve along its winding path from neck to stomach. In our practice, we look for compression or stretching of the vagus nerve being caused by excessive movement and instability of the C1-C2-C3 and other cervical vertebrae.
- The vagus nerve has direct connections with the facial nerve and the glossopharyngeal nerve and these three nerves the facial nerve glossopharyngeal nerve and vagus nerves they basically are the nerve supply as far as sensation goes to the tongue. The movement of the tongue, that’s the hypoglossal nerve working. The hypoglossal nerve also comes through the C1-C2 area and it also has connections with the vagus nerve but specifically, the facial nerve CN VII the glossopharyngeal nerve, cranial CN IX, and the vagus nerve, CN X, are interconnected.
The nerve pain from disc compression
- Upper cervical instability can nudge or push on the vagus nerve, this can lead to the development of vagal neuropathy or vagal neuritis or you can get hypoglossal neuritis or facial neuritis all because of upper cervical instability. This can cause the burning, the irritation, the awfulness of that horrible pain in the tongue on the roof of the mouth, and in the back of the throat.
- When the pain is just in the tongue is not anywhere else, often that’s irritation of the facial nerve. When there is burning in the back of the throat as well, or in the palette in the roof of the mouth that is indicative glossopharyngeal vagus nerve irritation. Often, this is from upper cervical instability.
Burning mouth syndrome is usually not an isolated problem. There are other symptoms.
- In every case I’ve ever seen a burning mouth syndrome the people also have other symptoms, it can be dizziness, ringing in the ears, clicking in the neck, migraine headaches, tension headaches, speech problems, swallowing problems, a lot of these symptoms again are problems with the vagus nerve.
In this video, Dr. Hauser explains the tell-tale sign of deviated uvula and its possible clue to Burning Mouth Syndrome
There are various clues that the vagus nerve is involved in burning mouth syndrome. One of them is to actually look at the uvula.
- Go to a mirror, shine a flashlight into your mouth and go “ahhh.” If your uvula deviates to the side, we call that a deviated uvula that is one of the biggest signs that the vagus nerve is not functioning correctly.
One of the ways that we objectively document that a person has vagus nerve problems or disrupted or blocked signals from the vagus nerve is by looking at the uvula at the back of the soft palate. When we ask the patient to say “ahhh,” the uvula (the small finger-like tissue that hangs at the back of the soft palate (often mistaken for the tonsils)) should remain centered in the throat.
See (0:40) of the video: When you say “ahhh,” the uvula should stay in the middle. See (0:48) the uvula deviates to the right. This means that the patient’s levator veli palatini (Levator palati) muscle is not supporting or elevating that side of the uvula. That means that this person likely has vagus nerve degeneration and compromised or blocked nerve impulses from the vagus nerve, more specifically, by the pharyngeal branch of the vagus nerve.
Numb tongue, burning mouth, and other tongue pain from nerve impairment due to cervical instability
Ross Hauser, MD, and Brian Hutcheson, DC discuss the nerves in the neck and face that affect tongue feeling and function, and when staying in prolonged positions can impair the nerves. The cervical instability one can experience during various movements and positions can cause painful symptoms like burning mouth or numb tongue, and difficulty speaking or moving the tongue.
In many cases of Burning Mouth Syndrome, we would recommend a tag-team approach of Prolotherapy injections to strengthen the cervical ligaments to help restore cervical spine stability and cervical curve realignment therapy through the use of specialized chiropractic care.
In almost all the cases of Burning Mouth Syndrome or numb tongue we have seen at Caring Medical, there has been some kind of dental work involved. Whether it’s wisdom teeth being pulled or a crown or a cavity.
- The upper cervical nerves, the C1, C2, C3 have connections to the hypoglossal nerve, the hypoglossal nerve controls the motion of the tongue.
- The upper cervical nerves, the C1, C2, C3 have connections to the trigeminal nerve which is the nerve that helps controls the muscles of the face and sensation that connects to the upper cervical in the spinal cord right
- The upper cervical nerves, the C1, C2, C3 have connections to the chorda tympani which is a branch of the facial nerve that influences sensation and taste in the tongue
Burning tongue / Numb Tongue Syndrome
Problems with these nerves and cervical spine instability can also cause problems of Numb Tongue Syndrome where half or more than half of the tongue feels numb tongue and often that occurs with motion.
If you have a tongue issue whether it’s numbness whether it’s pain if you have difficulty moving it, you have already been to a neurologist in you’re not good results what can be an answer?
We can sometimes find that under the certain motions of the neck, as pointed out, loss of tongue sensation with movement, we find under examination that motion of the cervical spine is causing nerve irritation that is impacting the tongue function.
We just had a case where we helped resolve a burning tongue issue. We provided on treatment of Prolotherapy (this patient will need more treatments to continue the stabilizing efforts) and we offered cervical spine curve correction. In this case, the patient benefited most from supine or laying down curve correction. We helped this patient enough on the first visit that she could go home lay on a Denneroll (a cervical orthotic device), which she utilized for a couple of hours and this helped alleviate the burning pain in her tongue. While this type of quick and immediate results may not be common or seen in all patients, it was good to see it in this patient.
The basic message, if you get rid of the irritation of the C1 or C2 nerve roots by positional changes of the cervical vertebrae, or a diagnostic nerve block, and this alleviates your problems. Then a further exploration of your burning mouth and tongue problems and its cervical spine connection should be explored.
Burning Mouth Syndrome a case study not requiring narcotic and anti-depressant medications. Treatment with Prolotherapy
If a person has burning mouth syndrome Prolotherapy treatments may offer relief. In this treatment, simple dextrose is injected into the cervical spine at the ligament attachments to the bone. The goal of the treatments is to tighten chronically stretched-out ligaments.
In a case history from Caring Medical, a patient had a dental procedure for gum disease. She then developed a severe burning mouth and underwent “hell” for the next two years. She had various teeth taken out, chelation for heavy metal poisoning, and a host of other treatments without relief of her burning mouth. Consultation after consultation with other providers continued to suggest a dental problem. That is until she had a Prolotherapy consultation where it was discovered that her pain was due to previously undiagnosed neck instability.
In our discussion with the patient, she revealed that she had a history of “tension headaches” and a clicking in her neck, for which she sought out occasional chiropractic manipulation. Her digital motion x-ray showed evidence of cervical instability in multiple areas. I told her in hindsight that it probably wasn’t the procedures themselves that caused this, but the head and neck position during the procedures that caused the condition.
Most healthcare providers are unaware of the stretching of ligaments that occurs when people are held in unusual or uncustomary positions for a long period of time, as in dental and surgical procedures.
I believe that during the gum procedure, her head was extended and her mouth was held open for over an hour which of course stretched her temporomandibular and upper cervical ligaments. This led to stimulation of the trigeminocervical nucleus in the cervical spinal cord, giving a burning mouth sensation. She had a double whammy, stimulus from the cervical and trigeminal nerves. Fortunately, after five Prolotherapy sessions to her jaw and neck, the patient reported the situation was resolving.
Summary and contact us. Can we help you? How do I know if I’m a good candidate?
We hope you found this article informative and it helped answer many of the questions you may have surrounding Burning Mouth Syndrome. Just like you, we want to make sure you are a good fit for our clinic prior to accepting your case. While our mission is to help as many people with chronic pain as we can, sadly, we cannot accept all cases. We have a multi-step process so our team can really get to know you and your case to ensure that it sounds like you are a good fit for the unique testing and treatments that we offer here. Contact our Neck Center team.
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This article was updated September 12, 2022