RESEARCH.
ZYGOMATIC MAJOR.
The Zygomatic Major is the principal muscle used in the act of smiling.
(
see fig 14 ) It's muscular attachment is approximately
two inches further to the side of the face. From it's cheek-bone
root, the zygomatic major travels diagonally downward to the outer corner
of the mouth. This diagonal path is the direction the smile follows
as it widens. The smile burrows into the face as much, if not more,
than it travels up.
In a broad smile there isn't a single part of the lower face that doesn't
move. The lips in particular are stretched tight around the curves
of the skull. The cheeks and the sides of the chin are mounted high,
pushed up out of the way. Deep creases appear where surfaces collide.
As a result small dents appear through the middle of the cheek. The
lips and jaw become pulled taut. The mouth goes from describing a
lazy curve to a hairpin turn.
Fig . 14 - The Zygomatic Major in action.