The orbicularis oris is the muscle that surrounds your mouth and allows you to pucker and close your lips. Why should you know about this muscle's location and purpose? Understanding the parts of our mouth and the functions associated with them can provide a better understanding of how we eat, talk and breathe.
The "Kissing Muscle" and Facial Anatomy
Also referred to as the "kissing muscle" because of its role in puckering the lips, the orbicularis oris is a ring of muscle that encircles the mouth. The fibers of the muscle are arranged in various directions rather than uniform circular rings. According to Anatomy Next, this muscle originates near the middle of the face at the maxilla (the upper jawbone that connects to your skull) and mandible (lower jawbone), surrounding the mouth at its corners. This muscle is anchored in the lips.
Orbicularis Oris Function
Anatomy Next explains that this muscle has two parts: the marginal part that aids in closing the mouth, and the labial part that pushes the lips forward. The two parts of this key lip muscle allow us to pucker up for a smooch and make facial expressions. This ring of muscle also helps with the task of forcibly releasing air from the mouth, allowing us to do everything from spitting watermelon seeds to playing musical instruments, such as the trumpet.
Your lip muscles are able to move and feel temperature and pain thanks to the seventh cranial nerve facial nerve (cranial nerve VII) moving through them. This same nerve helps you taste, produce tears and saliva and move other parts of your face, according to Family Practice Notebook.
Conditions That Affect Facial Muscles
Certain genetic and developmental disorders can affect the function of the muscles surrounding your lips. One type of developmental disorder that can affect the overall growth and maturation of the orbicularis oris muscle is a cleft lip or palate. In a person with a cleft palate, the bones that form the mouth do not fully develop or grow together properly. Unusual bone growth can affect the attachment of the facial muscles.
Constitutional Facial Acupuncture discusses how oral habits like smoking can cause the development of aging lines and wrinkles around the orbicularis oris. These wrinkles, sometimes called "lipstick lines," are caused by the action of sucking on cigarettes to inhale. Wrinkles won't harm your oral health, but quitting the tobacco habit is the best way to prevent these lines from forming and help keep your mouth healthy at the same time.
According to the U.K. National Health Service at University Hospital Southampton, diseases that damage or paralyze the facial nerves — such as Bell's palsy, Ramsay Hunt syndrome, Lyme disease and Guillain-Barré syndrome — may affect the muscles in the lower part of the face. Some of these conditions are temporary, others permanent. These diseases may be treated with surgery, physical therapy or medications, such as steroids, antibiotics or antivirals, depending on the diagnosis.
It's important to consult your doctor or dentist if you begin to notice weakness, tingling, numbness, pain or difficulty controlling any of the muscles in your head and neck. Early diagnosis and treatment can help keep all the parts of your face in good working order.