Through Grinding my Teeth my Masseter Muscle Has Increased? Will It Decrease in Time?

Thank you for your question. Botox or Dysport can be a very effective way to contour the jaw line by reducing the masseter shadow through the outer jaw skin. In addition, it can reduce symptoms of jaw clenching or grinding of teeth at night time. This is an advanced technique that requires a strong understanding of the underlying anatomy. Some side effects can results in some very unintented effects. This can include affecting the smile due to diffusion of the Botox into neighboring smile muscles. Over treatment can also overweaken your jaw muscles making it harder to chew food and causes your jaw muscles to relax too much when you sleep.The injection technique does vary by physical exam and the goals of the treatment. Facial contouring goals may change the injection sites themselves to affect different portions of the masseter as well as the dose. The strength of the masseters can be felt by palpation and also helps me to determine dosing. In general, I start with 15- 25 units of Botox (OR 50-75 units of Dysport) per side for most patients. If they have very strong masseters, then I may increase the dose, but more commonly ask them to return in three weeks for a touch up. Once you get the desired result, I let patients know that future treatments may require less to maintain the look or the jaw clenching symptoms, especially if they get treated as soon as they notice the symptoms return. This can be as soon as three to four months, but in some cases, patients report that it lasts six months or more. I find it depends on the dose we use and how many times we have done the procedure as the duration may lengthen for patients that repeat it regularly.

Thank you for your question. Botox will help relax the masseter muscle and can last up to 3 months. Maintenance is required. The muscle is not shrinking it's just relaxed and will come back when Botox wears off. I hope this helps.

Your masseter muscles may slightly decrease in size, but not likely enough to change the shape of your face, like injecting the proper dose of Botox would, over time. If you're inclined to have masseter reduction via Botox, visiting a reputable and well trained injector would be a great first step to assess and discuss options and details of what it can do for you.

Thanks for your question Ollie! Teeth grinding and jaw clenching can both cause the masseter muscle of the jaw to hypertrophy (become larger). Yes, it is true that the less you use a muscle the weaker it becomes as it atrophies (decreases in size). While a mouth guard at night helps to protect the integrity of your teeth from grinding, it does not necessarily stop the masseter muscle from contracting. Your muscle still has the ability to fully contract and remain strong. Treating the masseter muscles with Botox helps to relax and weaken the muscle so it is not able to contract as strongly, and with time it will atrophy. Botox can provide great relief to patients suffering from symptoms of TMJ. 
I've created a video where I review treating the masseter muscles with Botox/Dysport. I hope you find this information helpful in your research! 

You might see some lessening of the muscle protrusion, but the mouth guard is more of a dental-protection device. 

Botox is successfully used to prevent the strong contractions of the masseter. it can be a help in changing habitual action. But it's not a permanent fix and if the issues that cause the grinding in the first place aren't resolved, the muscle would likely revert to it's "built up" size once the Botox wears off and habits resume.

If your grinding is from stress (likely), then it makes sense you would look into some ways to reducing your stress levels. Also, becoming more aware in the day of how you physically respond to stress could help.

One dentist I know gave patients this phrase to say 3 times before going to sleep to help prevent night time grinding: "Lips together, teeth apart" . It might seem too simple, but self talk and self instruction can be quite powerful.