Will repeated treatment of bruxism with Botox cause more masseter reduction? (Photo)

Hi,Thank you for your question and sharing your photo.The masseters are a very bulky muscle for patients with bruxism and can take several weeks to months to atrophy and cause facial slimming. If your primary reason for botox in the masseters is for teeth clenching, you should notice improvement within 2-3 weeks after the treatment. If your provider still notices significant masseter activity on examination, additional botox can be injected to further relax the muscle. Hope this helps!

Thank you for your question Mini555! Yes your masseter muscle will continue to reduce in size (atrophy) as you receive repeated treatments.
Although the effects of Botox can initially kick in around day 3-5, it takes a full 2 weeks for Botox to reach full effect. At this time you will notice the muscle weaken and you won’t be able to contract it as strongly. However, the slimming effects can take up to 30 days to see, as the muscles requires time to atrophy. The effects of Botox to the masseter muscle last an average of 6 months. Once the effects wear off, the muscle will begin to function more frequently and regain its strength, slowly increasing in size again. How quickly it regains strength and size varies patient to patient and also depends on the dose of Botox injected. I recommend treatments every 6 months initially.

I’ve created a video that reviews treating the masseter muscles with Botox. I hope you find this helpful in your research!

Thank you for your question.  The masseter is one of the main muscles that allow you to move the jawbone (mandible) to chew.  You can feel this muscle at the back of the jaw when you clench your teeth. In bruxism, this muscle is overactive and grows.  This is similar to how the muscles grow in body builders that constantly train.  In some patients they can get so large that they create a visual distortion of the jawline.  I inject Botox into the masseter to paralyze it.  There are other muscles that help you chew so that is usually unaffected.  If the masseter is paralyzed for a prolonged time it will shrink (atrophy) and eventually become less prominent.  This requires regular treatments to prevent the muscle from building up again.  This is like how /the muscles shrink in the legs of people that have suffered from spinal paralysis.  

Hi, Thank you for your question. As each person requires a different amount of botox units for treatment of the masseter muscle, it is hard to tell if another treatment of botox will thin out the lower face more or not. An official consultation with your provider is needed to see if your masseter muscle has been properly treated with Botox. If it has been, there are other options to make the lower face appear thinner such as buccal fat removal or as you mentioned reduction of the mandible angle. 
Hope that helps, -Melody PAC

Mini555-
There is a range of Botox units that is used to treat the masseters and improve bruxism and everyone requires a little bit different number of units. If you are still having problems with jaw clenching, you may add more Botox and this will help reduce the problems and decrease the strength and size of the masseter muscles. The first couple of treatments you usually will require more Botox units in order to decrease masseter strength and size until the muscle relaxes and becomes smaller. You may also pair the treatments with wearing a retainer at night to help protect your teeth and prevent jaw pain and headaches while figuring out the correct Botox units. 

I hope this helps!

If the primary purpose is do thin the face, there might be other factors other than the masseters causing this. If the injector feels the masseters are relaxed fully, then no more Botox will help slim. If there is still tension in the muscles, more Botox can help. There are surgeries such as buccal fat reduction and jaw surgery that can help slim the lower face as well.

Thank you for your question and for sharing your photograph Mini555. I understand your concern. Botox is a purified protein used to address wrinkles associated with facial expression. When injected into the skin Botox will relax the muscles and smoothen out the overlying wrinkles. The most common areas of treatment are in the upper face. These include the horizontal lines seen on the upper forehead when one raises the brows, the vertical lines seen between the brows when one frowns (frown lines), and the crow's feet seen around the eyes when one smiles.It is difficult to make an assessment without a formal exam in the office where I can view the skin in multiple angles and observe wrinkles formed with facial expression. However, I hope the information provided here is useful.Botox can be placed in the masseter muscle in the lower face to contour the lower face and address pain associated with TMJ. In this area 20-40 units of Botox are used per side. Depending on the reason for the enlargement of the muscle, permanent results may be achieved. For example, some people have a habit of grinding, clenching, or biting their teeth subconsciously. Often times this happens in their sleep when they are not aware of it. Botox placed in this muscle will relax the muscle and the grinding, clenching, and/or biting will decrease. This will reduce the size of the muscle. If the brain gets accustomed to this and the person stops grinding, clenching, or biting, then the muscle will not become enlarged or as enlarged again. However, if the habit starts again, the muscle will likely get larger.

To determine if someone is a good candidate for this treatment it is necessary to look at a person’s lower face when biting and comparing it to when the person is not biting. If a bulge is seen on the outer portion of the jawline, then the person is likely a candidate. It can also be felt with the fingers when biting.
If I had a patient with the concern described here I would want to know the dose used at the first treatment. Often times better results can be achieved simply by increasing the dose at the next treatment, which is what I would likely recommend.With any injection, there are risks such as pain, bleeding, bruising, redness, swelling, tenderness, and infection. We take special precautions to minimize these risks such as using a painless technique. We also treat bruises with a laser as early as the next day. Bruises usually resolve within two weeks if untreated. After a laser treatment bruises usually resolve in 1-3 days, but may still take two weeks for full resolution. In addition to these risks, with Botox there is also a risk that the product spreads or diffuses to nearby structures. Spread to nearby muscles can lead to side effects such as the temporary appearance of droopy eyelids or a temporary asymmetric smile.

After a Botox treatment, I recommend that my patients avoid heat exposure, alcohol consumption, and strenuous exercise for 24 hours and not lie down flat for four hours. This is because all of these activities may possibly lead to the movement of the product and consequent side effects such as droopy eyelids. Although there have been no definitive studies shown that these actually occur and some physicians do not provide such aftercare instructions, in the absence of data I err on the side of caution and recommend that my patients avoid such activities.

Please consult with a doctor for specific recommendations. Good luck!

Hi Mini555, 
It's great that Botox had an effect on your masseters. Remember that Botox will only work on muscles - and not on fat or bone. More Botox treatments will reduce your masseters further - but be careful that it won't be to a point where you find it difficult to speak, chew or swallow. 
Some doctors are successful in contouring with Kybella. But since Kybella is not FDA cleared for this, you must pick a practice that has proven results.
All the best, 
Justin Harper, M.D.