Location
The transverse muscle of the chin, also known as the mentalis muscle, is a small muscle located in the face just below the lower lip. It is responsible for movements of the lower lip and chin, including puckering and protrusion.
Structure
In terms of structure, the transverse muscle of the chin is a thin, triangular muscle that originates from the inner surface of the lower jaw bone (the mandible) and inserts into the skin and underlying connective tissue of the chin. It is innervated by the mental nerve, a branch of the trigeminal nerve, which supplies sensory and motor fibers to the face.
Function
The main function of the transverse muscle of the chin is to assist in the movement of the lower lip and chin. When the muscle contracts, it pulls the lower lip and chin forward, allowing for protrusion and pouting movements. It also helps to keep the lower lip and chin in a forward-facing position, which is important for activities such as speaking and eating.
Clinical significance
In terms of clinical significance, the transverse muscle of the chin can be affected by various conditions or injuries. For example, it can be damaged during facial surgery or trauma, resulting in weakness or paralysis of the lower lip and chin. This can cause difficulties with speaking, eating, and facial expression. In addition, the transverse muscle of the chin can be affected by conditions such as Bell’s palsy, which is a neurological disorder that causes paralysis or weakness of the facial muscles.
