Mar 17, 2025 · Depressor labii inferioris is a paired facial muscle located in the chin region of the face. Due to its quadrangular shape, it is also called quadratus labii inferioris. It belongs to a broad group of muscles of facial expression, called the buccolabial group.

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]

The depressor labii inferioris (DLI) muscles move the lower lip downward to show the bottom teeth during smiling. Often, patients with facial paralysis have too much activity in this muscle on the unaffected side of their face.

Apr 30, 2023 · What Is the Depressor Labii Inferioris? The depressor labii inferioris, also called the quadratus labii inferioris because of its quadrilateral shape, is a facial muscle. It is a paired facial...

Aug 8, 2018 · Depressor labii inferioris is a paired facial muscle located in the chin region of the face. It is also called quadratus labii inferioris.

The depressor labii inferioris (DLI) muscle helps to lower and turn the lower lip outward and receives innervation from the marginal mandibular branch of the facial nerve. Paralysis of this muscle is a rare but potential complication of chin augmentation injections.

Jan 16, 2025 · The depressor labii inferioris muscle is found in the lower lip and is located deep to the orbicularis oris muscle, which encircles the mouth. It is located inferior to the labium superius oris muscle, which is responsible for raising the upper lip.

When you pull your lower lip down or to the side, you activate your depressor labii inferioris. This facial muscle originates from the outer surface of the mandible (lower jaw) and stretches upward to attach to the skin of the lower lip.

Jul 22, 2020 · The depressor labii inferioris, sometimes referred to as the quadratus labii inferioris, is a facial muscle whose function is to assist in the downward motion of the lower lip. A significant amount of fat is interspersed between the fibers of this muscle.

Explore the origin, insertion, and action of the depressor labii inferioris muscle, its innervation and arterial supply.