Uneven smile after Botox in the masseters. (Photos)

Yes, the risorius muscle must have been affected. This is not uncommon masseter injections. There's no way to know when this will go away or whether it will last 3 to 4 months. Nest time, I would suggest a smaller does and an injection into the lowest part of the muscle. You should follow monthly with your injector to document recovery.Best wishes, 

Dear SallyRS:
Thanks for sharing your photos. They are quite helpful and do indeed show your beautiful smile! I’m sorry for your troubles but the muscle activity in your cheek will return; generally in 3 to 4 months as the action of the Botox wears off.

Diagnosing the proper cause of TMJ and slimming your posterior jawline with Botox takes skill and experience. If you make little or no muscle bulge when clenching your teeth, then Botox injection to the masseter will produce little to no results and jaw surgery will be needed to reduce the jawline width.

The Botox does appear to have diffused into the muscles of the upper cheek causing the lowered nasolabial fold, corner of mouth and cheek fold.

I have found that exercise and TENS stimulation of the weakened muscles may help hasten the process of returning to normal.

Before you know it, your gorgeous smile will return. On your next venture, consult with a well experienced and Board Certified Plastic Surgeon or Oral Surgeon who uses Botox for TMJ and masseter therapy regularly. I wish you the best!