Get to know our oral cavity The structure of the oral cavity: The basic structure of the oral cavity consists of teeth, tongue, mucous membrane, etc. Among the components, teeth are the most important. Tooth structure A tooth is made up of three fundamental ingredients, enamel, dentin, and pulp cavity , as well as other accessory sub-structures. Enamel is the hardest substance in the body, even tougher than the bones. Its primary function is to protect the internal tissue from any injuries. Once this material is damaged, the tooth easily become susceptible to further damages. The second layer just underlying the enamel is dentin. This compartment is slightly softer than the enamel and contains many nerve endings. Once the dental cavities reach dentin, there will be pain sensation in the tooth. At the root region of the tooth, cementum forms the cover. It is slightly softer than the enamel and has dual roles of protecting and stabilizing the tooth. The second layer of the tooth root is dentin, and pulp cavity forms the next inner layer; both of these have identical functions as in the tooth crown. Peridontal ligament surrounds the tooth. This ligament structure attaches to the cementum and anchors the tooth in the bony socket of the jaw. The bony jaw socket provides a space for accommodating and stabilizing the tooth. A B C Superior labial frenulum Incisors Soft palate D E F Oral mucous membrane Tongue tip Tongue root G H I Inferior labial frenulum Canine Molars J K L ¦Ý¾¦«á¹Ô Soft palate Premolars

Tongue:
¦The tongue is a muscle made of interlacing muscle fibers. It houses taste buds and is responsible for the taste sensation. In general, the tip of the tongue is responsible for the sweet sensation, the root is for bitter sensation, the body is for salty sensation, and the perimeter of the tongue is responsible for sour sensation. The other major function of the tongue is sound pronunciation. Almost all phonetic symbols can't be pronounced without the aid of the tongue.

Oral mucous membrane
Oral mucous membrane is a layer of epithelial cells covering bones or muscles, specifically, the gums. Gums are attached to the bones and are a very intricate tissue. In addition to providing a cover for the bones, they also house rich networks of nerves and vessels and provide sensation and nutrients for the periodontal tissue. They can also receive the stimulation exerted by the food or other objects in the oral cavity, sensations such as cold, hot, touch, press, pain, etc. Through this transmission of sensation, gums form the oral cavity defense system along with teeth, and periodontal tissues (periodontal ligament, pulp cavity, alveolar bones).

Commonly seen oral diseases

Caries
There are four factors in cavities formation: host, food, time and bacteria.
When these four factors exist simultaneously, cavities may form. The host means the teeth. When the host receives food with carbohydrates (such as bread, sugar, cookies, etc), and the food remains in the mouth long enough for the bacteria to start growing, the bacteria will secret acidic substances. These substances will corrode the enamel and subsequently invade dentin, pulp cavity, and cavities finally form with the accompanying pain sensation.
Generally speaking, the most common locations for cavities formation are as follows:
1 . Cracks on the occlusion surfaces.
2 . Contact faces between teeth.
3 . Places near the gums, especially at the cracks on the occlusion surfaces of premolars and molars. Food debris and bacteria may easily be trapped at these places and dental plaques can form. Since it's not easy to clean contact faces between teeth, dental plaques may also accumulate here.
As the dental plaque accumulate, the acidic chemicals secreted by the bacteria will start corrode teeth and cause cavities. The cavities near the gums usually are a result of incorrect or forced brushing technique which leads to enamel wear.

Caries prevention
There are six ways to prevent caries:
1 . Educate the children the correct dental hygiene information.
2 . Brush your teeth correctly and effectively; use complementing products such as mouthwash.
3 . Balanced nutrition.
4 . Use of crack sealants to seal any tooth cracks or gaps and to lower accumulation of food debris and bacteria.
5 . Fluorine application.
6 . Regular dental examination.

Periodontal disease
Periodontal disease is a pathological condition in which periodontal tissues, including gums, periodontal ligament, pulp cavity, alveolar bones are affected. The primary cause is the accumulation of dental plaque on teeth or associated tissues. The toxic substance secreted by the bacteria causes inflammation of the gums, or even bleeding during brushing. Furthermore, the dental plaque may become calcified and turn into calculus. There may also be alveolar abscess condition. Periodontal tissues can also be damaged due to the presence of calculus and the action of bacteria. The periodontal damages in turn cause tooth loosening and the eventual tooth falling-off.

Prevention and treatment for periodontal disease
Since the primary cause is the dental plaque, hence the best prevention plan is to brush correctly and maintain good oral hygiene. If any symptoms surface, seek dentists assistance as early as possible. Removal of calculus (tooth cleaning) and drug treatments are some of the ways for preventing the disease from worsening.