The mylohyoid muscle is a thin, flat muscle that is located in the oral cavity and is an important component of the muscular system in the head and neck region.
Structure
The mylohyoid muscle is a thin, flat muscle with a triangular shape that is located above the front part of the digastric muscle. It is a muscle of the pharynx (derived from the first pharyngeal arch) and is classified as one of the suprahyoid muscles. The mylohyoid muscle is made up of two pairs of muscles, which together form a muscular floor in the oral cavity of the mouth.
Nerve supply
The mylohyoid muscle is innervated by the mylohyoid nerve, which is a branch of the inferior alveolar nerve. The inferior alveolar nerve is a branch of the mandibular nerve, which is itself a branch of the trigeminal nerve (CN V). The trigeminal nerve is the largest of the cranial nerves and is responsible for the sensation of the face and the movement of the muscles of mastication (chewing).
Development
The mylohyoid muscle develops from the first pharyngeal arch during fetal development. The first pharyngeal arch is one of the three pairs of arches that form during the early stages of development and give rise to various structures in the head and neck region, including the muscles of the face and neck.
Variations
There are several variations that can occur in the structure of the mylohyoid muscle. One variation is the presence of additional heads of the muscle, which can occur on either side of the main body of the muscle. Another variation is the presence of accessory mylohyoid muscles, which are small, additional muscles that can be found in the oral cavity. These variations are relatively uncommon and do not typically affect the function of the muscle.
Location
The mylohyoid muscle is located in the oral cavity, specifically in the floor of the mouth. It is positioned between the tongue and the mandible, and extends from the mandible to the hyoid bone in the neck.
Function
The mylohyoid muscle plays an important role in various functions of the oral cavity, including swallowing and speech. During swallowing, the mylohyoid muscle helps to elevate the hyoid bone and larynx, allowing the bolus of food to pass through the pharynx and into the esophagus. The mylohyoid muscle also helps to stabilize the mandible during speech, allowing for the proper movement and positioning of the tongue for clear and precise articulation.
In addition to its role in swallowing and speech, the mylohyoid muscle also helps to support the mandible and maintain the proper position of the teeth.
Clinical significance
The mylohyoid muscle is an important muscle for maintaining proper function of the oral cavity, and any dysfunction of the muscle can lead to issues with swallowing and speech. Dysfunction of the mylohyoid muscle can also cause issues with the position of the mandible and teeth, leading to issues with oral hygiene and dental health.
In some cases, the mylohyoid muscle may be involved in the development of certain oral conditions, such as temporomandibular joint disorders (TMJ) and bruxism (teeth grinding). The mylohyoid muscle may also be affected by certain medical conditions, such as Bell’s palsy, which is a condition that causes temporary paralysis of the muscles in the face.
