I love any name with a silent "P," and that includes "Pterygoid." This jaw muscle and I go way back. In my early years of practice as a Physical Therapist, I worked at a clinic specializing in Temporal Mandibular Joint (TMJ) Dysfunction, commonly known as "jaw pain." Since this muscle is involved with opening and closing the jaw, it can really cause problems when it does not function properly.
There are 2 divisions of the Pterygoid muscle, the internal or medial fibers, and the external or lateral fibers of the Pterygoid. The Internal/Medial pterygoid has 2 heads, one deep and one superficial. The deep head inserts onto the side of the sphenoid bone, which sits behind our eyes. The superficial head originates from the palatine bone on the roof of our mouth and the maxillary tuberosity which is a bump behind the top back teeth. Both of these heads insert onto the inside angle of the jaw bone, or mandible. The medial pterygoid works to close the jaw and move the jaw from side to side for chewing.
The External/Lateral Pterygoid originates from the great wing of the sphenoid bone and pterygoid plate, and inserts on the condyloid process of the mandible, which is the part of the jaw bone that rests inside the joint, beneath a disc made of cartilage, and serves as the hinge point or axis for opening and closing the jaw. When the external/lateral pterygoid contracts, it works to open the jaw, protrude it forward, and move it side to side, along with the internal/medial pterygoid.
What signs or symptoms result from problems with Pterygoid? Headaches, facial pain, ringing in the ear, or ear pain are some common symptoms people experience when their pterygoids are not working properly. Clicking in the joint is common when the disc is sliding inefficiently within the joint space. If the disc gets dislocated, the jaw can get stuck open or closed. The Temporal Mandibular Joint (TMJ) gets swollen from the improper mechanics of the muscles around the area, which adds to the discomfort. People who clench their teeth or grind them at night often have trouble with their pterygoids, and may also have imbalances in some of the other jaw muscles. Chewing, talking, and even kissing can become very difficult for people with TMJ Dysfunction. None of that is very fun, as you can imagine!!
What causes problems with the Pterygoid? Muscular imbalances throughout the head, spine and pelvis can contribute to postural alignment imbalances that affect the position of the head and jaw bones, and put added stress on the pterygoids. People often injure their jaw in car accidents, or with a direct blow to the jaw or face. Some people have stress, tension, and unresolved anger issues and clench their teeth habitually. This puts a lot of stress on the joints and can worsen the symptoms noted above.
How can we feel the Pterygoid working properly? You will feel a subtle muscle contracting inside the jaw joint as you open and then close your teeth gently. You can really feel the pterygoids inside the jaw joint as you move your jaw back and forth from side to side, gently. You can place your fingertips on the outside of the jaw joint just in front of your ears and feel the disc slide along with the lower jaw bone. Notice if you feel one side or the other move forward more quickly or if you feel the disc popping as you move. A normal jaw will open to between 40-50 mm of opening if all goes well.
Here's hoping your Pterygoids are doing well and keeping your mouths and heads happy as you enjoy yummy, nourishing foods and laugh and socialize with your family and friends!