The corner of my mouth is no longer raising when I smile. What went wrong with my Masseter Botox?

I had 15 units injected in both masseters on May 18th, 2014. The doctor injected 2 areas On the right side of my face when he went to inject the lower part, I felt a squirting of some sort and as though it wasn't going entirely into the muscle. When I went back to show him that the corner of my mouth is no longer raising when I smile, he acknowledged and said the Botox most likely migrated to my zygomatic muscles. He says this will take a few months to go away. However, if my zygomatic muscles are not being used now, won't I have to retrain them overtime to go back to normal?

Doctor Answers 8

Botox for Facial slimming

Botox does a good job in facial slimming (masseter injections)  but it sounds like the zygomatic muscle was affected in the process.  Unfortunately there is nothing you can do about this problem now but it will go away in approximately three months.  


New York Dermatologist
5.0 out of 5 stars 78 reviews

Botox for the Masseter (Jaw Slimming)

Thank you for the question. You hit the nail on the head: the zygomaticus muscles were affected by the Botox injections. This will resolve slowly over about 3 months. When injecting the masseter for jaw slimming, it is important to place the injections laterally and inferiorly (near the angle of the jaw).  In addition, the injections are placed deeper than typical Botox injections. Please follow up with your provider to discuss your concerns.

Evan Ransom, MD
Bay Area Facial Plastic Surgeon
4.9 out of 5 stars 113 reviews

Masseter Injection Problem

The masseter likely wasn't injected properly and the points were too medial and superior.  With that said, any issues will return to normal in 2-3 months.  Nothing will be permanent.  I wish you the best of luck, Dr. Emer. 

Jason Emer, MD
Los Angeles Dermatologic Surgeon
4.8 out of 5 stars 196 reviews

Smile muscles and botox

Yes, that was the answer I was going to say. MOre than likely it impacted your zygomaticus muscle and it should come back to normal when the Botox wears off.

Steven Wallach, MD
New York Plastic Surgeon
4.1 out of 5 stars 29 reviews

Uneven smile after Botox

Since Botox is temporary, no permanent damage was done to your smile muscles. Over the next few weeks to months, you will notice strength returning to your smile spontaneously. This means no muscle retraining will be required...only time.

Ramona Behshad, MD
Saint Louis Dermatologic Surgeon
5.0 out of 5 stars 6 reviews

The good news is the dose was small so the unwanted effects...

won't last too long...most likely the injection targeted the wrong muscle...either the injection was too far superior or too close to the nose side of the cheek...not sure I accept the migration story...and it should take some time for the muscle to lose function...should not be right after the treatment...and then the muscle should work again within as little as 3-4 weeks to as long as 2-3 months...don't know what the squirting sensation was...no matter where the botox was injected you shouldn't feel anything squirting unless some dripped onto the surface of the skin which means even less made it to the muscle...

Ken Landow, MD
Las Vegas Dermatologist
4.6 out of 5 stars 9 reviews

Botox injection for slimming masseter caused abnormal smile - Botox improperly injected is reason.

There are a couple muscles which could cause this problem, the zygomaticus or the risorius muscle.  If injected too high, the zygomaticus will be affected, to anterior, the risorius will be affected.  Either way, time will heal the problem and you have no worries about it being permanent.  Steve Weiner, Facial Plastic Surgeon.

Steven F. Weiner, MD
Panama City Facial Plastic Surgeon
4.7 out of 5 stars 41 reviews

Change in smile

The usual reason for a squared off smile after masseter injection is that the injection was placed too high.
It should not happen when injected correctly near the masseter insertion.
It will wear off in about 3 months. 

Elizabeth Morgan, MD, PhD
Atlanta Plastic Surgeon
4.6 out of 5 stars 43 reviews

These answers are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.