ANATOMY

Mentalis Muscle is a paired central muscle located at the tip of the Chin. It is a muscle for the Lower Lip. The muscle originates from the Mandible to provide stability to lower lip. Its fibers start from the Incisive Fossa of Mandible coursing downward to insert in the Chin. It is named so because of its association to the emotional and thoughtful facial expressions.

BLOOD SUPPLY

Blood supply to the Mentalis Muscle is provided by the Facial Artery.

INNERVATION

The muscle gets its innervations from the Zygomatic Facial Nerves.

FUNCTION

The main function of Mentalis is to perform Pouting by causing the protrusion of the lower lip and the elevation of the skin of Chin. The exaggeration of the emotional facial expressions like sadness or displeasure is carried out through this muscle.

CLINICAL SIGNIFICANCE

Geniospasm is one of the disorders associated with Mentalis. Geniospasm is a rare Genetic Disorder which causes the involuntary quivering of lower lip and chin usually under stress in childhood.

To make the Skin smaller by surgery is called Mentoplasty and to make it bigger is called Genioplasty, in both cases the Mentalis Muscle is detached during the surgery and when reattached becomes damage. For avoiding the damage to the muscle Botox is used.

Mentalis Muscle is also strained due to the deformity of Chin.