Thank you for your question. Botox or Dysport can be a very effective way to contour the jaw line by reducing the masseter shadow through the outer jaw skin. In addition, it can reduce symptoms of jaw clenching or grinding of teeth at night time. This is an advanced technique that requires a strong understanding of the underlying anatomy. Some side effects can results in some very unintented effects. This can include affecting the smile due to diffusion of the Botox into neighboring smile muscles. Over treatment can also overweaken your jaw muscles making it harder to chew food and causes your jaw muscles to relax too much when you sleep.The injection technique does vary by physical exam and the goals of the treatment. Facial contouring goals may change the injection sites themselves to affect different portions of the masseter as well as the dose. The strength of the masseters can be felt by palpation and also helps me to determine dosing. In general, I start with 15- 25 units of Botox (OR 50-75 units of Dysport) per side for most patients. If the have very strong masseters, then I may increase the dose, but more commonly ask them to return in three weeks for a touch up. In your situation, I would say that 150 units is a very strong dose. I would return to your injector to be assessed. If your smile is affected, it will take several months for the effects to wear off, but it will return.
