Does Masseter Botox work for TMJ and jaw slimming?

Masseter Botox is a procedure where Botox is injected directly into your masseter muscle – this is one of the muscles located on the side of your face that helps you chew.

The masseter Botox procedure has become popular because it can slim a square face and reshape the jaw line. The cosmetic benefits of this procedure were discovered by accident – the original reason Botox was injected into the masseter muscle was to relieve teeth grinding (also called bruxism) and jaw pain or tension.

Bruxism and jaw pain are commonly associated with temporomandibular joint (TMJ) disorder – a condition with many different causes (such as arthritis, joint erosion, or habitual grinding) that affects almost 10 million Americans.

Masseter Botox is an off-label use, meaning the FDA has not approved Botox for this purpose. Consequently, the long-term side effects of regular use are unknown.

Masseter Botox before and after

This before and after masseter Botox photo can show you what to expect from treatment.

The actual results for you may vary depending on your face structure and the amount of Botox used.

How many units for Masseter Botox?

Masseter Botox is given as two injections into the masseter jaw muscle on each side of your face or four injections in total.

• Because the masseter muscles are used for chewing, it is the strongest muscle in the face and larger-than-usual doses of Botox are used.
• A typical dose is 20 to 30 units of Botox per side, or 4 injections (2 each side) of 10 to 15 units each injection.
• This can be increased or decreased as needed depending on the desired result.

How long does Masseter Botox last?

A noticeable slimming of the jawline is usually seen within 1 to 2 weeks of a masseter Botox injection, although it may take up to 4 weeks for the full effects to be seen.

The effects are long-lasting, and it takes up to 4 to 6 months for a masseter Botox injection to wear off.

How much is Masseter Botox?

Botox typically sells for $10 to $15 a unit. The cost for the masseter Botox procedure depends on the size of your master muscle and the amount of product used to shrink the muscles.

For a person of average build, around 20 to 30 units are needed on each side which means the cost of one masseter Botox procedure would range from about $400 to $900 depending on the clinic and the amount used.

How long does Masseter Botox take?

It typically takes less than 30 minutes for the 4 injections (2 on each side of the jawline) to be given during a masseter Botox procedure.

How does Masseter Botox work?

The masseter muscle is one of four muscles that help us chew. This muscle extends from the base of the cheekbone to the bottom of the mandible and is easily felt along the lower jaw when your teeth are clenched.

Large masseter muscles can be caused by regularly chewing gum, clenching the jaw, grinding teeth, or by inexperienced musicians learning wind instruments. Some people are just born with larger masseter muscles.

A large or overactive masseter muscle can make the lower face appear square-shaped and bulky. Botox injected into this muscle decreases nerve signals to the muscle, temporarily paralyzing the muscle which reduces its size because it is not as active anymore, making the face look more contoured, defined, and slimmer.

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Who should not get Masseter Botox?

Masseter Botox should not be given to people:

• With allergies to onabotulinumtoxinA, Botox, or other botulinum toxin products
• Who are pregnant or breastfeeding
• With bleeding disorders
• With neuromuscular disorders
• With skin infections in the areas being treated.

Masseter Botox gone wrong

If you are thinking of getting masseter Botox make sure you consult with a qualified health provider who has experience in facial anatomy and in performing the procedure, because there are plenty of stories on the internet of masseter Botox gone wrong.

• An experienced provider of masseter Botox will strike a good balance between slimming down the masseter muscle while still retaining the ability to chew and bite normally.
• The areas of the muscle closest to the mouth are typically not injected which allows the person to still smile but still achieve the tapering effect.

Problems arising from masseter Botox include:

• Crooked or lopsided smiles
• Inability to smile or laugh
• Paralyzed or drooping upper lip
• Unwanted wrinkles around the mouth.

Some of these effects are not necessarily due to an excessive dose of Botox or the wrong placement but can be due to the toxin diffusing (spread) into surrounding muscles. For example, the muscle that controls smiling (the depressor anguli oris) is reasonably close to the masseter muscle and the toxin may spread to affect this muscle as well.

Other severe side effects of Botox include allergic reactions, muscle weakness, difficulty swallowing or breathing, vision changes, or bleeding but these are rare. See emergency help right away if any of these happen to you.

Call your doctor at once if you have a hoarse voice, drooping eyelids, vision problems, severe eye irritation, severe muscle weakness, loss of bladder control, or trouble breathing, talking, or swallowing.

How can I avoid problems from Masseter Botox?

Always make sure your Botox injections are performed by somebody who has experience in facial anatomy and follow your post-treatment instructions exactly. This may include:

• Remaining upright for at least 4 hours after the procedure to reduce the risk of the neurotoxin diffusing into surrounding tissues or muscles
• Avoiding exercise, hot baths, or saunas 24 hours after the procedure
• Avoiding alcohol and nicotine on the day of the procedure
• Do not apply pressure to the treatment area
• Apply ice packs if you notice redness or swelling in the treated areas.

If you do notice any unwanted effects from masseter Botox, ring your healthcare provider immediately. Because the effects of Botox are usually temporary, most will wear off in a few weeks.