A total dose of four units of botulinum toxin A was injected into the right levator labii superior muscle, two units into the right levator anguli oris
muscle, two units into the left depressor anguli oris muscle, and two units into the right inferior orbicularis oris muscle.
The artery is superficial to the mandible, buccinator muscle, and levator anguli oris
Then in quick succession, we add the smiling muscles, levator anguli oris
(attaching just below the eye to lift the corners of the mouth) and the sadness muscles, levator labii superioris (Fig 4) (which deepen the nasiolabial fold when crying or being serious) and the depressor anguli oris, the disgust muscle (a triangular muscle attaching to the lower jaw at the side of the mouth) which lowers the corners of the mouth.
the buccal branch, which innervates the procerus, the zygomaticus major and minor, the levator labii superioris, the levator anguli oris
, nasal muscles, the buccinator, and the orbicularis oris
The toxin is typically injected into the zygomaticus major and minor, the levator anguli oris
, and the risorius.