Awful smile following Botox in masseter. How long will this last & are results permanent?

The changes and asymmetry of the smile following Botox injection are secondary to unintended differential weakness of other muscles, but the good news is that the effect is temporary and will be gone in 3-4 months maximum time.

Thank you for your question!  I am sorry that you are having these difficulties after your Botox injections.  Botox injections into the masseter muscle help to sculpt the face, and reduce the width of these muscles.  You may be noticing some changes because of relaxation of the masseter muscle, which is not directly involved with smiling.  I would discuss your concerns with your injector, and possibly have a follow up visit. I hope that this helps!-David Gilpin

The problem is that the risorius muscles was hit with the Botox. This muscles lies in front of the masster. This will take 2-3 months to resolve and it will go back to normal. Don't worry. This is on the higher side of dosing. I start at 15 per side.