The temporalis muscle is also known as the temporal muscle. It is a fan shaped muscle that lies against the temporal bone. The word temporal is derived from Latin for time. It is thought that this bone and muscle are named for the fact that this is where gray hair shows up first, thus showing the passage of time. The temporalis is one of many muscles that helps us move our jaw. This muscle is responsible for helping us close our mouth when it is open and with a movement called retraction (pulling in) when the jaw is protruded (sticking out). In other words, when you stick out your lower jaw the temporalis helps bring it back into alignment.
Some cool trivia:
The temporalis passes underneath a bone called the zygomatic arch which is part of your cheek bone.
Why we care about this muscle as your chiropractor:
This is a clinically important muscle to me when I am treating temporomandibular joint (TMJ) or when I am working to rehab people with Bell’s palsy. The temporalis directly moves the TMJ, if there are problems with muscle fibers not firing correctly or if there are myofascial trigger points (colloquially know as knots) in the temporalis then the jaw won’t open and close smoothly. This will then cause pain in the TMJ because the joint can no longer move smoothly. Over time this can cause wear and tear in the joint, so getting muscle mechanics addressed as soon as possible for the TMJ patient is ideal.
When doing rehab for Bell’s palsy the temporalis being loose is important because the temporal branch of the facial nerve lies over the temporalis. Keeping the temporalis muscle loose and adhesion free can help speed the progression of recovery.