5 affected muscles and its actions
- Frontalis
Action: It is responsible for raising the eyebrows and gives wrinkles to the forehead horizontally
- Zygomaticus Major
Action: It lifts the corner of the mouth and it helps you smile
- Orbicularis Oculi
Action: Closes the eyelid and it helps when you blink and wink
- Buccinator
Action: It pushes the cheek against the teeth that enables us to chew and blow air
- Platysma
Action: It depresses or lowers the corners of the mouth that contributes to frowning
Mechanism of Muscle Weakness
Bell's palsy often happens because the seventh cranial nerve which controls the facial muscles becomes swollen and inflamed. Also, inflammation can be caused by certain illnesses like viral infections but many cases of Bell's palsy have no clear cause or idiopathic.
Other Symptoms