The masseter muscle is the main muscle of the jaw used to chew food. If you place your hand on the side of your jaw and clench your teeth, you will be able to feel your masseter muscle. In patients who habitually clench their jaw or grind their teeth, this muscle can become enlarged, which is called masseter hypertrophy. This enlargement creates the appearance of a wider face and a square jaw. Not only is masseter hypertrophy unappealing cosmetically, it can also lead to TMJ (temporomandibular joint) disorders, which can cause pain, swelling, and difficulty chewing. By injecting Botox into the masseter muscle, it not only helps to treat the symptoms of TMJ, but also helps to decrease the appearance of the muscle, essentially giving the face a more oval appearance, as opposed to a square. As long as the injection is done correctly by an experienced provider, there should not be any impact on surrounding muscles or cause any facial sagging.
To create the perfect Botox brow lift, I will typically inject 3 units of Botox at the lateral tail of the brow into the orbicularis oculi muscle. This muscle acts to depress the brow, so by injecting Botox into the muscle, it will create a lift of the lateral (or outer) brow.
