According to Tortora & Derrickson, Bell’s Palsy causes the side of a person’s face to drop. It prevents a person to wrinkle their forehead as well as close their eyes and pucker their lips. Apart from these, the person may also experience difficulty in swallowing and even drooling. With these, we can derive that the following muscles, in accordance to their actions, are affected:
|
MUSCLE |
ACTION |
|
Frontal belly |
Wrinkles forehead skin horizontally |
|
Corrugator supercilii |
Wrinkles forehead skin vertically |
|
Orbicularis oculi |
Closes the eye |
|
Mentalis |
Elevates and protrudes lower lip and pull skin of chin up or pouting |
|
Orbicularis oris |
Closes and protrudes lips–kissing; compresses lips against teeth; shapes lips during speech |
Tortora, G. J., & Derrickson, B. (1975). Principles of Anatomy & Physiology. http://ndl.ethernet.edu.et/bitstream/123456789/1717/1/36%2c2012.pdf.pdf