Mejilla

Mejilla is the term used in anatomy to describe the cheek, the lateral region of the face between the eye and the mouth. It extends from the infraorbital margin and zygomatic arch to the lower border near the mandible, forming the external contour of the midface.

Structure and components: The mejilla consists of skin and subcutaneous tissue overlying muscle and fat. The buccal fat pad occupies a major portion of the mid-cheek, contributing to volume and contour. Deep to the subcutaneous tissue lie the muscles of facial expression, notably the buccinator, along with the zygomaticus major and minor, risorius, and related fibers, which insert around the mouth and contribute to expressions. The cheek is bounded internally by the mucosa of the oral cavity.

Innervation and vascular supply: Motor control of the cheek muscles is provided by the facial nerve (cranial nerve VII). Sensory input from the skin of the cheek is supplied by branches of the trigeminal nerve, primarily the infraorbital nerve (V2) and buccal branches of V3. Blood supply comes mainly from the facial artery and its branches, with drainage to the facial vein and related venous pathways.

Function: The mejilla plays a key role in facial expression, articulation and speech, mastication, and protection of underlying structures. It contributes to the contour and symmetry of the face and to the seal of the oral vestibule.

Clinical notes: Cheek injuries, infections such as cellulitis, and trauma can affect appearance and function. Reconstructive procedures may target contour restoration or adjustment of the buccal fat pad, and facial nerve injury can lead to asymmetry in cheek movement.