The digastric muscle is located in the neck, beneath the jaw. This muscle belongs to the suprahyoid muscle group, and it assists in opening and closing the jaw.
Curved in shape, this muscle extends from the mastoid process at one end to the symphysis menti at the other. The mastoid process is a part of the temporal bone located behind the ear. The symphysis menti is a suture, or seam, located in the front, middle of the lower jaw.
The term ‘digastric’ refers to two bellies within the muscle itself. This includes the posterior and anterior bellies. The posterior is attached to the mastoid process, and it is supplied by the digastric branch of the facial nerve. The anterior extends from the mandible’s lower border. It is situated close to the symphysis. The anterior belly connects to the nervous system via the trigeminal nerve, which is also known as the fifth cranial nerve. The facial artery delivers oxygenated blood to the anterior belly, while the occipital artery supplies the posterior belly.
The digastric muscle also features an intermediate tendon. This serves as the end of both bellies and the tendon connects to the stylohyoideus muscle, located in the neck just below the lower jaw.