Dental Anatomy & Physiology

The human mouth has various structures and organs that work together to help chew food and keep a person healthy, according to "Torres and Ehrlich Modern Dental Assisting." Dental teams must understand the anatomy and physiology of different parts of the oral cavity to use as a reference point for dental procedures and to spot any irregularities during clinical examinations.

Teeth Types

• The teeth in an adult are divided into four categories--incisors, canines, premolars and molars. Incisors are single-rooted teeth with a sharp, thin edge. These teeth are located at the front of the mouth and are designed to cut food. The tongue side of an incisor is shaped like a shovel to help guide food into the mouth. Canines, also known as cuspids, are located at the "corner" of a person's dental arch. The canines cut and tear foods, which requires the application of force. The canines are the longest teeth in the human mouth and thus also are some of the most stable teeth. Premolars, also called bicuspids, are a cross between canines and molars and sit behind the canines. These teeth have pointed cusps on their cheek side that hold the food, while the cusps on the tongue side grind it. Molars are much larger than premolars and chew or grind up food in the back of the mouth.

Teeth Contours

• All teeth have a curved surface except for when the tooth is fractured or worn. Some surfaces are curved outward, or convex, while others are curved inward, or concave. Curvatures on the facial surface--the surface of a tooth closest to the face--and on the lingual surface, which is the surface of the tooth closest to the tongue, provide natural passageways for food. This protects the gum from the impact of foods during chewing. The mesial and distal areas are two other surfaces of teeth. The mesial surface is the surface of the tooth toward the midline of the oral cavity, while the distal surface is the surface distant from the midline. The contours of the mesial and distal surfaces provide normal contact between teeth and help preserve the teeth through self-cleansing.

Tongue

• The tongue is mostly made up of muscles and is covered with a thick layer of mucous membrane and thousands of tiny projections called papillae. Inside the papillae are the sensory organs and nerves for taste and touch. The tongue is an important part of dental anatomy and physiology studies because it helps a person to position food while eating, taste food, swallow food and cleanse the oral cavity. Taste buds are located on the top side, or the dorsum side, of the tongue. Saliva helps to stimulate these organs to detect flavors.

Gingiva

• The portion of the tooth that is visible in the mouth, called the crown, is surrounded by a cuff of gingival tissue. The gingiva, known as the gums, is mucosa--or moist tissue--that covers the jaw areas and surrounds/protects the necks of the teeth. The gingiva is self-cleansing and is both attached and unattached in various parts of the mouth.

Palate

• The hard palate in the roof of the mouth separates the nasal cavity above from the oral cavity below. Behind the top dental arch's central incisors is the incisive papilla, a pear-shaped pad that serves as the site of injection for anesthesia of the nasopalatine nerve prior to procedures such as dental fillings.