Jaws: TMJ, Bruxism, Their Relation to MS---and Why We're Gonna Need a Bigger Boat

Last updated: November 2021

In my mid-1960s youth, a Jawbreaker was a newfangled kind of gumball that was not a regular on my candy store wish list. Every Saturday afternoon I’d walk or bike up to Holliday’s five and dime in the quiet hamlet of Sylvania, Ohio and buy penny candy, most of which was comparatively easy to masticate than those hard-shelled swirly-colored mini-bowling balls with the soft chewy centers. The first time I ever tried to break through the granite-like outer shell—initially by using my sharp incisors (to no avail) and then the crushing force of my molars—I heard a loud pop on the left side of my jaw followed by soreness that lasted the rest of the day. In an uncharacteristic moment of child-stage common sense, I decided not to tempt fate again and stuck with the much safer Smarties, Sweetarts, chocolate coins, candy necklaces and buttons, Slo-pokes, colored wafer flying saucers, wax pop bottles, and Pixie Sticks. I wish that wise move could have prevented what would happen later on—and I don’t mean the seven cavities I developed from eating all that sugar.

By age 12, I’d developed such severe molar sensitivity after eating lemon drops or drinking a Coke that I couldn’t bite down on anything for hours. My complaining prompted no particular interest from the adults in my life, nor any explanation from my childhood dentist. Then at age 29, during a first appointment with a new dentist, I was told my molars were worn down to the dentin, that soft, yellow layer below the enamel. “You have the teeth of an 80-year-old,” he quipped. “Do you grind your teeth in your sleep?” It took every fiber of restraint to keep myself from sarcastically shooting back: “Dude, how could I possibly know that if I’m ASLEEP?”

By young adulthood, I had developed a popping, painful jaw (a.k.a. Temporo-Mandibular Joint Disorder, or TMJ), excessive enamel wear and extreme bruxism—a.k.a. jaw-clenching. What, you might be thinking, have these conditions to do with multiple sclerosis? A group of researchers made a small preliminary study to rule out a connection with MS. Here’s how it went:

In 2010, a tiny cohort of 10 MS patients plus 11 non-MS patients serving as a control group were studied to quantify the change in intracranial diameter between the… surfaces of the temporal bones during jaw clenching, using an ultrasonic pulsed phase locked loop (PPLL) device... A sustained jaw clenching force of 100 lbs was used to measure change in acoustic wavelength (ÆL) as the measure of intracranial distance between the temporal bones. The increase in magnitude of bi-temporal bone intracranial expansion was approximately six times greater in subjects with MS compared to controls. Therefore, jaw clenching/bruxism is associated with more marked displacement of the temporal bones and expansion of the cranial cavity in patients with MS than in control subjects.1

Researchers used this significant difference between MS patients and the control group to postulate some other connections with MS as well. For example, we know that Vitamin D deficiency is a risk factor in developing MS. Vitamin D is also essential in metabolizing calcium, so a deficiency can decrease bone density, thereby exacerbating the increased distance between the two cranial plates.

What’s more, investigators surmise that an increase in temporal bone displacement can cause periventricular BBB (Blood Brain Barrier) leakage, thereby allowing lymphocytes to enter the cerebrospinal fluid and attack the white matter. This could characterize jaw clenching-induced temporal bone trauma/displacement as one possible “trigger” that can activate the disease in a person that is genetically predisposed to developing MS.

To take that idea even further, ICP (Intracranial Pressure) brought on by jaw clenching could also affect periventricular venous blood flow, causing iron deposits and lesions to accumulate in the white matter. This makes a tenuous connection to Chronic Cerebrospinal Venous Insufficiency (CCSVI).

The authors of this study express their uncertainty about whether bruxism (jaw clenching) comes first and activates MS, or whether active MS causes jaw spasms, TMJ and jaw clenching. Either way, however, they stress the importance of dentists paying close attention to TMJ and bruxism issues, considering it a possible red flag for the onset of MS.

This is why I think we’re gonna need a bigger boat. By that I mean two things...

... It’s a clear indicator that we with MS require an integrative medicine model for our health care. Info sharing between our dentists and neurologists is as important as that of our urologists, primary care docs, endocrinologists, rheumatologists, cardio-vascular specialists, gynecologists, pharmacists, and anyone else directly involved with our care. Study investigators also posited that there is some solid science behind the notion that tooth decay can activate MS. Therefore…

... It’s high time that dental care is invited on board the big medical care boat. Conventional medicine and health insurance still won't sink their teeth into the idea despite the fact that we know for sure how gum disease can directly cause serious heart damage if the patient isn’t treated with a prophylactic dose of antibiotic prior to having a dental procedure. Moreover, dental insurance coverage is not nearly as generous as medical insurance. Restorative procedures, gum surgery, root canals and abscess treatment are only covered at 50%. Our pocketbooks are empty enough as it is; I think we’ve all foregone dental work at some point because we couldn’t handle the debt or cash outlay. Those days really need to end soon.

Some questions to ponder:

Do you suffer from night time jaw clenching and teeth grinding? Gnashing your pearly whites at night has been noted as a familiar symptom among MS patients.

Have you had a discussion with your neurologist and/or dentist about which of your dental issues might impact your MS?

Jaws. It’s not just a scary movie. It’s one more body part to monitor in managing your MS.

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This article represents the opinions, thoughts, and experiences of the author; none of this content has been paid for by any advertiser. The MultipleSclerosis.net team does not recommend or endorse any products or treatments discussed herein. Learn more about how we maintain editorial integrity here.

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