Muscle spasms can be incredibly painful, and when they occur in your jaw, they can make it difficult to do simple things, such as talking, smiling and eating.
To eradicate these forcible and involuntary contractions of your jaw muscles, you have to first determine the cause.
Knowing the cause gives you a starting point to craft an effective treatment plan. There are several reasons why you might experience spasms in your jaw.
Some of these are relatively common while others are related to conditions you may not have heard of.
What is the Physiology of a Muscle Spasm?
No matter where in the body a spasm occurs, the general physiology is the same. Understanding the physiology helps you to know what is happening in your body when this issue happens.
Under normal circumstances, when muscles are resting, calcium is stored in the muscle’s reservoir, referred to as the sarcoplasmic reticulum. Calcium is blocked by magnesium so that it is not able to release from this reservoir.
Now, for a muscle to contract, it receives a nerve signal that essentially tells this reservoir to release some of the calcium.
This results in an array of reactions where ATP causes a muscle fiber’s myosin and actin filaments to engage, according to research published by Dr. Siegfried Mense. The muscle then contracts.
Various factors can cause muscle contraction, such as lack of blood flow, severe cold, metabolic abnormalities or excessive exercise.
The contraction stimulates sensory receptors, even more, increasing the contraction’s intensity.
Over time, positive feedback develops, and the body essentially starts to see this as normal.
Then, whatever factor causes the contraction only needs to be present in small amounts for spasms to occur.
So, those who have jaw spasms have something going on in their bodies that is acting as a trigger to cause their jaw spasms.
This trigger needs to be uncovered to determine why you are having spasms in this area.
Exploring the Different Temporomandibular Joint Disorders
There are several types of these disorders. The temporomandibular joint (TMJ) connects the side of the head and jaw.
It is in front of the ear. It is formed by the glenoid fossa and mandibular condyle of the temporal bone.
This video describes the anatomy of this joint. It also shows disc displacement to better understand this joint and the associated disorders.
These disorders are characterized by jaw dysfunction. Most cases are associated with the ligaments and muscles of the temporomandibular joints, or the different internal derangements located within the joints.
When this joint’s internal derangements are to blame, this can result in abnormal movement of the glenoid fossa’s mandibular condyle or the articular disk.
The disc provides cushioning between the bone surfaces. Abnormal movement may result from:
- Grinding and clenching teeth
- Arthritis or similar systemic disorders
- Missing teeth
Treating joint derangement typically starts with more conservative measures, including pain medications, muscle relaxation, bite splinting, resting the jaw and physical therapy.
If these provide to improve the condition, surgery might be performed.
Mandibular condylar hyperplasia is a type of TMJ disorder. When this disorder is present, the condyle continues to grow when it should have already naturally stopped.
Experts have yet to determine when this condition begins or how long it will persist, according to research presented by Sergio Olate, et al.
It results in an asymmetric facial deformity. This condition can also cause a unilateral dental open bite or crossbite.
Imaging studies are typically performed to make a diagnosis, with a CT scan being able to confirm it.
If active growth is occurring, excising the condyle joint’s bony prominence (condylectomy) is generally recommended.
After growth has ceased, doctors generally suggest surgical mandibular repositioning. Reducing the inferior border is another option is there is a significant increase in the height of the mandibular body.
Mandibular condylar hypoplasia is characterized by the mandibular condyle being underdeveloped. This can cause a deformity of facial fullness.
It may result from infection, irradiation or trauma during the growth period, but there are cases deemed idiopathic.
Typically, one side of the jaw and face is affected. Doctors may choose to either shorten the side that was not affected or lengthen the side that is underdeveloped to provide better symmetry.
Orthodontic therapy before surgery may also be beneficial.
TMJ ankylosis is characterized by fusion or immobility of this joint. Trauma or infection are the typical causes, but some cases are attributed to rheumatoid arthritis, psoriasis or ankylosing spondylitis, according to NIH GARD. It can also be congenital.
Condylectomy may be performed to treat this condition. Following surgery, doctors have patients perform jaw-opening exercises. These are necessary to maintain the correction made during surgery.
TMJ arthritis is the next disorder to explore. Infectious arthritis, osteoarthritis, secondary degenerative arthritis, traumatic arthritis and rheumatoid arthritis can all cause symptoms in the temporomandibular joint, according to Merck Manual.
The symptoms are similar to those of other joints in the body caused by these conditions.
Diagnosis typically involves a physical exam of the TMJ and imaging studies. In some cases, doctors might recommend arthroscopy to get a better view of the area.
This is an imaging study that involves inserting a small camera into the TMJ joint space.
Treatment is largely dependent on the type of arthritis causing the joint symptoms.
In addition, doctors might recommend pain medications, muscle relaxers, tricyclic antidepressants, physical therapy, mouth guards or oral splints.
In some cases, conservative measures are not sufficient to alleviate symptoms. If this happens, doctors might recommend surgical procedures:
- Arthrocentesis to remove inflammatory byproducts and debris
- TMJ arthroscopy if open-joint surgery is contraindicated for the patient
- Open-joint surgery to replace or fix the joint
- Corticosteroid injections to relieve pain and inflammation
- Modified condylotomy if jaw locking is affecting the patient
What is Hemimasticatory Spasm?
This is a very rare trigeminal nerve disorder characterized by the unilateral jaw-closing muscles experiencing paroxysmal involuntary contractions, according to a report created by Jin Kim, MD, et al.
It is possible for this condition to be idiopathic. However, it is usually associated with localized scleroderma or progressive facial hemiatrophy.
Progressive facial hemiatrophy is characterized by the soft tissues and skin starting to waste away in the half of the face affected.
The degeneration is progressive and slow. Over time, patients may have a sunken appearance.
Localized scleroderma is a condition where the skin starts to become thicker as a result of excessive collagen deposits.
It can affect the skin and the muscles located below. The damage and skin changes can be permanent, but the localized form does not become the systemic form of this disease.
Phenytoin and carbamazepine therapy have been tried for this condition. However, these oral drugs have been shown not to benefit most patients. It appears that Botox injections into the affected muscles are usually most effective.
When Botox is injected, it attaches to the nerve endings in the area so that they are not able to release chemical transmitters.
These transmitters are what tell muscles to activate and contract. So, when Botox prevents these transmitters from doing their job, the injected muscle is not able to go into spasm.
Get the Facts About Hemifacial Spasm
This is a type of neuromuscular disorder that causes people to experience involuntary spasms on just one side of their face.
The spasms tend to occur frequently and can affect all elements of the side of the face affected, including the cheek, eye, and jaw.
It usually begins with the eyelid on the affected side of the face twitching intermittently. Over time, the spasm becomes more forceful and may cause the eye to be forced closed.
The spasm continues to spread until all muscles on the affected side of the face are impacted.
In some cases, no cause can be identified. However, a tumor or facial nerve injury can cause this spasm.
The most common cause is a blood vessel pressing down on the facial nerve where it comes out of the brainstem.
While rare, it is possible for both sides of the face to be affected, according to a report created by E.K. Tan and J. Jankovic.
In these instances, patients usually have the spasm on one side of the face first and then it spreads to the other side.
Diagnosis involves diagnosing this condition and determining the underlying cause. This generally involves a physical examination and MRI using a contrast dye.
Botox injections are a common course of treatment to help stop the affected muscles from going into a spasm.
The injections are generally done every three to four months. Anticonvulsant drugs might also be beneficial.
Microvascular decompression surgery may be considered. This involves opening the dura of the brain so that the surgeon has access to where the facial nerve comes out of the brain stem.
The blood vessel applying pressure to the nerve is located and a spongelike material is placed between it and the nerve to alleviate the pressure.
Learn More About Oromandibular Dystonia
This condition is characterized by involuntary spasms in the muscles responsible for moving the jaw and mouth. This can cause the tongue and mouth to be pulled into abnormal positions.
Spasms in the jaw, drooling and slurred speech are common symptoms. Patients might also have difficulty swallowing and chewing.
In most cases, this condition develops between ages 40 and 70, according to the Dystonia Medical Research Foundation. Women also tend to be affected more than men.
In most cases, this condition happens after dystonia in the eyes or neck are already present. However, it is possible to manifest without these other dystonia types.
The purpose of treatment is to try to manage the muscle spasms. Botox injections might be beneficial. Patients will usually receive these every three to four months.
Certain medications may be recommended to help to target certain brain chemicals that contribute to muscle movement. Massage, speech therapy, stretching, occupation and physical therapy may be used.
In severe cases, there are two surgical procedures doctors might explore. Deep brain stimulation uses precisely placed electrodes to control muscle spasms. The electrodes are implanted into specific brain areas.
Selective denervation surgery is another option. This is done to control muscle spasms via cutting the nerves associated with those muscles.
What You Need to Know About Trigeminal Neuralgia
This condition is characterized by the trigeminal nerve being inflamed. This nerve works to give sensation to the face and its three branches go to the forehead, lower jaw, and cheek.
Every year, it is estimated that 150,000 people are diagnosed with this condition, according to the American Association of Neurological Surgeons.
The pain it causes is described as excruciating and disabling. It is a spasming pain that can affect the cheek, teeth, lips, forehead, jaw, gums and eye.
It usually only affects one side of the face, but in rare cases, both can be affected.
This condition occurs when the trigeminal nerve is being pressed down by a blood vessel.
It may result from aging, a tumor, multiple sclerosis, stroke, surgical injuries or facial trauma.
Drugs to treat the underlying condition and those to treat this condition specifically are the most common treatment.
For the trigeminal neuralgia, doctors might prescribe muscle relaxers, anticonvulsants or Botox.
When medications are not enough, surgery may be needed to damage the nerve to alleviate pain or remove pressure on it by the offending blood vessel.
These procedures may include:
- Microvascular decompression
- Glycerol injections
- Brain stereotactic radiosurgery
- Radiofrequency thermal lesioning
- Balloon compression
Taking a Look at Amyotrophic Lateral Sclerosis (ALS)
This is a type of progressive neurodegenerative disease. It causes disability by destroying nerve cells to the point where they break down and die.
Approximately 90 to 95 percent of cases are not inherited and occur sporadically, according to NIH Genetics Home Reference.
In the other five to 10 percent of cases, there is believed to be a genetic inheritance.
In the early stages, slurred speech and limb weakness and muscle twitches are common.
Other muscle spasticity and twitches, including in the jaw area, are possible in the early stages.
There is no cure and the damage done cannot be revered. Treatment is primarily focused on preventing complications, slowing down disease progression and making the patient comfortable.
Treatment often involves a combination of medications and therapies, such as physical therapy, speech therapy, breathing care and occupational therapy. Some patients may also qualify for clinical trials.
If you are experiencing jaw spasms, make an appointment with your doctor. It is important to determine the underlying cause.
Not only is this imperative for your health, but once the cause is uncovered, you and your doctor can work together to develop a treatment plan.