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This action causes the muscle to keep food pushed back on the occlusal surface of the posterior teeth, as when a person chews. By keeping the food in the correct position when chewing, the buccinator assists the muscles of mastication. [4] It aids whistling and smiling, and in neonates it is used to suckle.
The zygomaticus major muscle is a muscle of the face. It arises from either zygomatic arch ; it inserts at the corner of the mouth. It is innervated by branches of the facial nerve (cranial nerve VII). It is a muscle of facial expression, which draws the angle of the mouth superiorly and posteriorly to allow one to smile. Bifid zygomaticus ...
The facial muscles are just under the skin (subcutaneous) muscles that control facial expression. They generally originate from the surface of the skull bone (rarely the fascia), and insert on the skin of the face. When they contract, the skin moves. These muscles also cause wrinkles at right angles to the muscles’ action line. [2]
These muscles move the skin, creating lines and folds and causing the movement of facial features, such as the mouth and eyebrows. These muscles develop from the second pharyngeal arch in the embryo. The temporalis, masseter, and internal and external pterygoid muscles, which are mainly used for chewing, have a minor effect on expression as ...
The risorius muscle is a highly variable muscle of facial expression. It has numerous and very variable origins, and inserts into the angle of the mouth. It receives motor innervation from branches of facial nerve (CN VII). It may be absent or asymmetrical in some people. It pulls the angle of the mouth sidewise, such as during smiling.
The zygomaticus minor muscle is a muscle of facial expression. It originates from the zygomatic bone, lateral to the rest of the levator labii superioris muscle, and inserts into the outer part of the upper lip. It draws the upper lip backward, upward, and outward and is used in smiling.
Lip lines and forehead lines can also develop from laughing and smiling or chewing and puckering — like if you smoke cigarettes or drink most of your water out of a straw. Wrinkles on the ...
The orbicularis oris is not a simple sphincter muscle like the orbicularis oculi; it consists of numerous strata of muscular fibers surrounding the orifice of the mouth, but having different direction. It consists partly of fibers derived from the other facial muscles which are inserted into the lips, and partly of fibers proper to the lips.