Depressor labii inferioris

The depressor labii inferiois muscle is a quadrilateral facial muscle located in the jaw area that draws the lower lip down and to the side as in an expression of irony. Originating on the oblique line of the mandible, it inserts on the skin of the lower lip and blends with the orbicularis oris muscle. It extends the fibers of the platysma muscle while its own fibers are combined with yellow fat. Also known as the quadratus labii inferioris and the quadratus menti, the depressor labii inferioris allows for facial expressions, the playing of the trumpet, and kissing. It is aided by the other muscles that lower the lip -- the risorius, the depressor anguli oris and the mentalis. Innervated by the facial nerve, ailments affecting the depressor labii inferioris include myalga, stroke, myopathy, strains, Bell's palsy, lacerations, contusions, infectious myositis, tears, atrophy and neuromuscular diseases. Symptoms related to these ailments include decreased movement of the lip, loss of muscle control, paralysis, and muscle spasms.

Written and medically reviewed by the Healthline Editorial Team
Co-developed by:

In Depth: Depressor labii inferioris

Debugging Tools

Level: 2
Frame: 1
Toggle Hotspot
VP Data Tool
HexTable json from Steve
Steve's ajax layer update call:
[still on original layer]

Ad values:

adModel.dfpAdSite: hn.us.hl.bm.x.x.rfs
adParams['k1']: othermusculoskeletaldisorders,structure_of_depressor_labii_inferioris_muscle_(body_structure),8964739

More on BodyMaps

Take a Video Tour

Learn how to rotate, look inside and explore the human body. Take the tour

BodyMaps Feedback

How do you like BodyMaps? How can we improve it? Tell us what you think
Advertisement
Advertisement