One of the considerations of the soft tissue aesthetics of the lower face is that of the masseter muscle. Being one of the larger muscles of the face, it has a large surface area covering the bony jaw angles. (ramus of the mandible) Despite its important functions of jaw opening and closing and in chewing it is largely ignored unless it becomes too big. Masseter muscle hypertrophy causes noticeable aesthetic bulges over the jaw angles particularly when chewing and makes the lower face wide and more full.
In the January 2018 issue of the journal Plastic and Reconstructive Surgery an article was published entitled ‘The Masseter Muscle and Its Role in Facial Contouring, Aging, and Quality of Life: A Literature Review.’ In this paper the authors performed a literature review of the treatment of masseteric muscle hypertrophy with Botox injections and its outcomes. Their results supported the successful reduction of prominent masseter muscles with improved lower facial shapes with injection into the lower posterior portion of the muscle directly over the bony jaw angles. Besides the aesthetic improvement, it also reduced the symptoms of teeth clenching and grinding. Adverse effects were very few and self-limiting.
Prior to Botox injections the reduction of masseteric muscle hypertrophy was done surgically with a high rate of complications. Besides bleeding the muscle was often left irregular in outer contour. Botox changed all of that to a non-surgical procedure with no significant complications. While not permanent, its effectiveness is undeniable. With size reduction there is also reduced pain for those afflicted with bruxism.
While most commonly used in Asian patients for aesthetic jaw contouring I have treated an equal amount of non-Asian patients with exclusive symptoms of bruxism/clenching and/or unilateral masseter muscle enlargement causing facial asymmetries.
Dr. Barry Eppley