Botox can be used to slim the posterior part of the face through injections that involve the masseter muscle. This is done in the office. We can use topicals and ice to make the injections more tolerable. We basically inject the botox next to the bone and into the masseter / jaw muscles. The botox weakens the muscle so that it eventually loses some of its bulk. The botox takes 2 weeks for maximal effect but the volume reduction is different. The volume reduces most rapidly in the first 1-2 months with the maximum at 3-4 months with slow reduction over the course of a year. At twelve months, 50% of the volume that was decreased will be regained at this point. I usually tell people to wait at least a month to see how it looks before adding more botox. The usually starting dose is 20 units. But I find that it is most effective when 40 units are started for each side. But the cost of botox can be high so usually people like to start at 20 units on each side. Many plastic surgeons price botox less when more is put in. When you put in 80 or more the price is usually around 11-12 dollars per unit. Botox in the masseter can decrease the prominence of the jaw muscles so that the lower part of the face looks more slim and this can give the female face a more attractive appearance. A larger lower third is relatively a musculine trait and less feminine. Botox in the jaws and masseter muscle can also help some tension headaches that are due to muscle overactivity and temporal mandibular joint disorders. People who have night time teeth grinding / clenching can have bad headaches. Botox in the jaws is needed less frequently than the facial muscles for other cosmetic reasons. Some people can get away with doing botox to the jaws on a yearly basis.
I hope that helps.
Thanks for reading, Dr Young
Dr Young specializes in Facial Cosmetic and Reconstructive Surgery and is located in Bellevue near Seattle, Washington