Final answer:
The surface away from the midline of the mouth on the right involves the buccinator muscles and mucous membranes of the cheeks, which play an important role in the movement and function of the jaw, as well as the overall structure of the oral cavity.
Step-by-step explanation:
The surface away from the midline of the mouth on the right is related to the lateral structures of the oral cavity. When we talk about lateral excursion, we refer to the side-to-side movement of the mandible away from the midline, toward the right or left side. This is part of the normal range of motion for the jaw, which is essential for various functions like chewing and speaking.
The oral cavity is composed of several structures, including the cheeks, tongue, and palate, which all frame the mouth. The outer covering of the cheeks is skin, transitioning to a mucous membrane on the inside. This mucous membrane is made up of non-keratinized, stratified squamous epithelium. The inner part, closer to the midline, is made up of the gums and teeth, and moving away from the midline, we find the buccinator muscles located within the cheeks, which are responsible for keeping food inside the mouth while chewing. The lips, which cover the orbicularis oris muscle, have a significant role when it comes to the aesthetics and functionality of the mouth, including activities like kissing and articulating speech.
The inner surface of each lip is attached to the gum by the labial frenulum, which is a midline fold of mucous membrane. This entire assembly is essential for maintaining the homeostasis of the oral environment and facilitating complex oral functions. Moreover, during embryonic development, proper fusion of the maxilla bones and overlying muscles at the midline is crucial to avoid birth defects such as cleft lip or cleft palate.