Search results
Results from the WOW.Com Content Network
The depressor anguli oris arises from the lateral surface of the mandible. [1] Its fibers then converge. It is inserted by a narrow fasciculus into the angle of the mouth. [1] At its origin, it is continuous with the platysma muscle, and at its insertion with the orbicularis oris muscle and risorius muscle.
The four classical muscles of mastication elevate the mandible (closing the jaw) and move it forward/backward and laterally, facilitating biting and chewing. Other muscles are responsible for opening the jaw, namely the geniohyoid , mylohyoid , and digastric muscles (the lateral pterygoid may play a role).
It passes anterior-ward deep to the platysma and depressor anguli oris muscles. It provides motor innervation to muscles of the lower lip and chin: the depressor labii inferioris muscle, depressor anguli oris muscle, and mentalis muscle. [1] It communicates with the mental branch of the inferior alveolar nerve. [citation needed]
The hyoglossus is a thin and quadrilateral extrinsic muscle of the tongue. It originates from the hyoid bone; it inserts onto the side of the tongue. It is innervated by the hypoglossal nerve (cranial nerve XII). It acts to depress and retract the tongue.
The depressor labii inferioris muscle helps to depress and everts the lower lip. [1] It is the most important of the muscles of the lower lip for this function. [1] It is an antagonist of the orbicularis oris muscle. [1] It is needed to expose the mandibular (lower) teeth during smiling. [1]
Levator labii superioris alaeque nasi muscle; Depressor labii inferioris muscle; Levator anguli oris; Buccinator muscle; Mentalis; The platysma is supplied by the facial nerve. Although it is mostly in the neck and can be grouped with the neck muscles by location, it can be considered a muscle of facial expression due to its common nerve supply.
This is a branch of the mandibular nerve (CN V 3), itself a branch of the trigeminal nerve (CN V). [1] It emerges from the mental foramen in the mandible. [2] It divides into three branches beneath the depressor anguli oris muscle. One branch descends to the skin of the chin. Two branches ascend to the skin and mucous membrane of the lower lip.
Muscle Action Risorius: Smirk Buccinator: Aids chewing by holding cheeks flat Levator labii superioris: Elevates upper lip Levator labii superioris alaeque nasi muscle: Snarl Levator anguli oris: Soft smile Nasalis: Flare nostrils Orbicularis oris muscle: Purse Lips Depressor septi nasi: Depresses nasal septum Procerus: Moves skin of forehead