The mouth, also known as the oral cavity, serves as the initial gateway to both the digestive and respiratory systems. This complex structure facilitates daily functions like eating, speaking, and breathing, by preparing food for digestion and enabling clear communication.
Your Teeth
Teeth are hard structures anchored within the jaw, for the mechanical breakdown of food. Adults possess 32 permanent teeth, each shaped for specific functions. Incisors, the eight front teeth, have sharp edges for biting and cutting food, while the four pointed canines, located next to them, are designed for tearing. Premolars, or bicuspids, situated between canines and molars, feature ridges that help crush and grind food into smaller pieces. The molars, the largest teeth at the back of the mouth, have broad, flat surfaces with multiple cusps, making them efficient grinders for food preparation before swallowing.
Each tooth consists of a visible crown above the gum line and a root embedded in the jawbone. The crown is covered by enamel, the hardest substance in the human body, providing a durable chewing surface and protection. Beneath the enamel lies dentin, a softer, yellowish layer that forms the bulk of the tooth structure and supports the enamel. At the tooth’s core is the pulp, a soft tissue containing nerves and blood vessels that supply nutrients and sensation. Teeth also play a role in speech, forming sounds by controlling airflow and interacting with the tongue and lips.
Your Tongue
The tongue is a muscular organ for oral functions. Its flexibility and strength allow it to manipulate food during chewing, pushing it between the teeth and forming it into a soft mass for swallowing. The tongue’s surface is covered with small projections called papillae, housing taste buds. These taste buds contain specialized cells that detect the five basic tastes: sweet, salty, sour, bitter, and umami.
Beyond taste and food manipulation, the tongue is for speech articulation. Its movements shape airflow and interact with other mouth structures to produce sounds for language. The tongue’s movement also contributes to oral hygiene by cleaning teeth and removing food debris.
Other Essential Soft Tissues
Soft tissues work with teeth and the tongue to maintain oral health and function. The gums, or gingiva, are the pink tissues that surround the base of the teeth. They protect the tooth roots and the underlying jawbone, forming a tight seal that acts as a barrier against bacteria and mechanical forces during chewing.
The palate forms the roof of the mouth and has two distinct parts. The hard palate, at the front, is supported by bone and separates the oral cavity from the nasal cavity. Behind it, the soft palate, composed of muscle and connective tissue, extends backward. At its rear hangs the uvula, a small, conic projection. Both the soft palate and uvula move upwards during swallowing to prevent food from entering the nasal passages and also contribute to speech sound formation.
The cheeks and lips form the external boundaries of the oral cavity. These muscular structures are important for containing food during chewing and preventing saliva from escaping the mouth. They also contribute to facial expressions, speech sound articulation, and possess sensory receptors that judge food temperature and texture.
The Salivary System
Saliva, a clear fluid composed mainly of water, is produced by several salivary glands within and around the mouth. The three pairs of glands are the parotid, submandibular, and sublingual glands. Saliva plays multiple roles, beginning the digestion of carbohydrates through enzymes like amylase and moistening food to aid in swallowing. It also acts as a protective agent, cleansing the mouth by washing away food particles and neutralizing acids, reducing bacterial growth and tooth decay.