Injury to the masseter muscle may cause pain, difficulty chewing, or swelling around your jaw and face.
This article will describe the anatomy of the masseter muscle, its function, and associated health conditions.
You have two masseter musclesone on the left and one on the right.
The three layers of the masseter are the superficial layer, the intermediate layer, and the deep layer.
The muscle fibers originate from thezygomatic archof your skull, also known as your cheekbone.
The muscle layers then converge and insert into theramusof yourmandible(jaw bone).
The trigeminal nerve, the largest of the cranial nerves, consists of three main branches.
Blood Supply
The masseter muscles receive blood supply from themassetericartery that emerges from themaxillaryartery in your skull.
The maxillary artery is divided into three parts: mandibular,pterygoid, andpterygopalatine.
What Does the Masseter Muscle Do?
The major function of the masseter muscle is to elevate your jaw bone.
This brings your teeth together, as in the chewing motion.
It works with the temporalis and lateral and medial pterygoid muscles to perform this function.
The superficial fibers of the muscle protrude from your jaw, bringing it forward into an underbite position.
The deep fibers of the masseter muscle also serve as a major stabilizer of the temporomandibular joint.
When you clench your teeth together, the muscle contracts to keep the TMJ in the correct position.
There are over 30 different TMD disorders.
Pain in the jaw or with chewing are the most common symptoms.
TMD is often self-limiting and may go away with appropriate treatment.
Surgical options do not typically produce effective outcomes.
Trauma and Jaw Fractures
Trauma to the face or jaw may injure the masseter muscle.
Other obvious signs of trauma, such as broken teeth or bleeding in the mouth, may occur.
Symptoms of a jaw fracture may include:
The treatment of a jaw fracture depends on its severity.
If the fracture is moderate to severe, you may need surgery.
Surgical repair may include placing stabilizing plates and wiring the jaw to help it heal correctly.
Trauma to the jaw can also cause a dislocated jaw.
To help stabilize the jaw, patients are generally instructed not to open their mouths widely for six weeks.
Seek Immediate Medical Treatment
It is important to seek medical care immediately for trauma to the jaw.
This is because a broken or dislocated jaw may cause a blocked airway or other breathing difficulties.
Trigeminal Neuralgia
Trigeminal neuralgiaaffects thetrigeminal nerve, the fifth cranial nerve.
The trigeminal nerve has three branches:ophthalmic, maxillary, and mandibular branches.
The ophthalmic branch affects the scalp and the front of the head.
Symptoms oftrigeminal neuralgiatypically include intense, debilitating pain attacks.
The pain may last seconds to minutes and is usually one-sided.
It is sudden and intense and is usually triggered by some contact or vibration on the cheek.
Treatment includes medications to manage the pain, surgical interventions, and alternative therapies such asacupunctureor chiropractic care.
The condition is benign, and the main complaint is its aesthetic changes to the face.
Patients may experience facial asymmetry, changes to the lines in the face, and a more prominent jawbone.
There are several treatment options.
Mouthguards,medication for anxiety, muscle relaxers, and physical therapy may also be utilized.
Another option is the use ofbotox, or botulinum toxin pop in A, injections in the masseter.
The injections work by paralyzing the muscle, which eventually shrinks after disuse.
The main disadvantage of this treatment option is that it must be repeated to remain effective and is costly.
Lastly, various surgical interventions are utilized to reduce muscle size.
Rehab considerations for a jaw injury depend upon the cause of your condition.
Once healed, gentle motion should be started to stretch and strengthen the jaw muscles slowly.
Temporomandibular joint disorders may require a multi-faceted approach to care.
You may benefit fromphysical therapyto help alleviate your symptoms and restore normal jaw motion and function.
Treatments may include:
You may also benefit from using a mouth guard to properly position your TMJ.
Your healthcare provider may recommendsurgery to correct the joint structuresif there is a severe problem within the joint space.
Summary
The masseter muscle plays an essential role in jaw function, stability, and chewing.
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