What Muscle Is Used in Smiling? Many people have heard the old wive’s tale that it takes more muscles to frown than to smile but that is not the entire story. While there is one main muscle always in use when smiling — the Zygomaticus Major — there are groups of muscles necessary for both smiling and frowning.
The Muscle Used in Smiling — Zygomaticus Major
Known as the Smiling Muscle, the zygomaticus major is most responsible for our smile. It works in conjunction with up to 43 other facial muscles to provide a wide array of smiles. From a sly grin to a full, toothy smile that lights up the whole face, there are a million different smile configurations.
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Even a fake smile or grimace uses the zygomaticus major. The muscles are all tied to one nerve, called the facial nerve. Branches or nerve bundles split off from the main nerve and work together to form our smiles. We’ll discuss the facial nerve more shortly, but for now, the five primary muscle groups responsible for smiling are:
- Zygomatic
- Temporal
- Mandibular
- Cervical
- Buccal
These groups include the 43 muscles that work together to form our facial expressions.
OMG What Adorable Dimples
Why do some people have dimples and others don’t? Why are some dimples barely perceptible while others are more pronounced? Are dimples a genetic trait? Do people wonder why some people have dimples and others don’t?
We wondered. The main cause of cheek dimples is a difference in muscle structure of the zygomaticus major. In people without dimples, the zygomaticus major travels from the zygomatic bone in one cluster, where it connects to the corner of the mouth.
When the zygomaticus major splits into two bundles before connecting to the mouth the two portions retract separately. This split is known as a bifid zygomaticus major muscle. One bundle connects to the corner of the mouth while the other connects slightly below forming a dimple.
People may have a dimple on one cheek and not the other. Although most people think dimples are a genetic trait, there has not been enough scientific study to determine this as fact.
One thing we know for sure is that dimples are adorable!
Different Types of Smiles Convey Different Meanings
Everyone has a unique smile. Even though there are only 7 basic facial shapes (round, oval, diamond, pear, heart, oblong, and square) our teeth and lips combine to create individual looks. Some resemblance among family members is due to genetics, but our smiles go deeper than bloodlines.
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Some people are always smiling, while others maintain a more stoic look. We see smiles from a smirk to a roaring, open-mouthed guffaw. Each of our facial expressions can convey a different meaning. They can symbolize confusion, joy, and so much more.
Are there specific types of smiles that are easily recognizable? Sometimes, yes, but additional facial configurations can alter the meaning of a smile. For instance, one may be smiling with their mouth while their eyes relay the different message of dissatisfaction.
Although a smile is the movement of the muscles of the mouth, our entire face conveys the actual meaning of each smile.
A closed-lip grin can signify reassurance or dominance, depending on the rest of the facial signs. We can see a goofy smile that assures us the smile is not a threat, while another similar grin may chill us to the bone. Being able to interpret smiles takes a lifetime of study.
The one sure type of smile is the freely offered reward smile. This is the smile we use when we play with a baby. This is the smile that normally offers a “reward” of a return smile. We use it as we hold a door open for a stranger, and they smile back in thanks. We greet family and friends with this smile. It can be an ice breaker at a job interview or a first date. This is the smile that moves the world.
How Facial Muscles Work Together to Smile
Most of the 43 muscles we use to smile are under the control of the seventh cranial nerve. This is also referred to as the facial nerve. It begins at the cerebral cortex, emerging from the skull in front of the ears. From there it separates into five branches known as the primary branches which we discussed earlier.
Each branch connects to a different part of the face, which is why we have such a wide variety of possible expressions. The branches control the movement of the muscles that control the mouth. The specific muscles are:
- Depressor anguli oris
- Zygomaticus major
- Zygomaticus minor
- Levator labii superioris
- Risorius
The muscle of expression, and especially the zygomaticus major and minor works to pull the orbicularis oris upward to form the smile. The orbicularis oris circle the mouth, controlling the movements associated with the mouth and lips. When the branches of the facial nerve produce a smile, they send signals to our brain that releases dopamine.
Our facial muscles work in groups to produce our various expressions. Some smiles use only two muscle pairs, while a hearty smile can use ten muscle pairs. To frown, we commonly use three muscle pairs to drop the lower lip and turn down the corners of the mouth.
Smile and the World Smiles with You
It is often said that smiles are contagious. There is scientifically documented proof of that. Additionally, we witness this phenomenon daily during our interactions with other people.
When you’re feeling a bit down, try smiling. Even the simple act of faking a smile instructs our brain to release dopamine, which is a mood lifter. This is also why we find it almost impossible not to return a smile when someone smiles at us.
Make the world a better place — smile more!
Make Your Smile the Best
People who like their smile tend to smile more. If you are not happy with your smile, it may be time to see Amboy Orthodontics. With either braces or Invisalign, you can discover the smile of your dreams! To request an appointment for a consultation, simply complete and submit the online Appointment Request form.
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