ABSTRACT
Proper knowledge of the anatomy and physiology of muscles is required. Especially around the modiolus, which has a complex equilibrium of agonistic and antagonistic actions of multiple muscles. Excessive or inappropriate injections lead to undesirable side effects. Adhering to the correct treatment protocols can lead to highly satisfying results, reducing bunny lines and peri-oral lines, correction of a gummy smile, and facial asymmetries. Nasal rhytides or bunny lines can be treated by Injecting 2-4 U/5-10 sU of toxin at a depth of 2-4 mm, just above the center of the levator labii superioris aleque nasii muscle, and just medial to the vertical line between ala and medial canthus. The orbicularis oris muscle is used to purse the lips, for example when drinking through a straw. Weakening of this muscle may therefore lead to unwanted restriction in normal eating and drinking movements. Pay attention to the dosage to prevent this complication; start low and titrate to the desired result.
