Teeth are divided into three parts: crown, neck and root. The crown is the part we can see, and it is the part where the teeth are exposed outside the gums. The surface of the crown is covered with a layer of enamel, which is the hardest tissue in the human body, and its hardness is similar to that of the time. The root is embedded in the alveolar process of the upper and lower jaws. The root surface is covered with a layer of cementum. The neck of the tooth is a slightly thinner part between the crown and the root of the tooth, which wraps the gum. Teeth are mainly composed of dentin, and the internal cavity is called tooth cavity. The cavity of movable teeth is filled with connective tissue, nerves and blood vessels, which are collectively called dental pulp. Blood vessels and nerves enter and exit from the apical foramen of teeth. When suffering from dental caries, bacteria corrode enamel and dentin and enter the pulp cavity, which stimulates nerves and makes the pain unbearable. (See Figure 37) Students should take the following measures to protect their teeth:
1. Develop good brushing habits. Rinse your mouth with warm water after meals and brush your teeth once in the morning and evening. Don't brush your teeth too often, it will damage your teeth, and don't brush your teeth for too long. Pay attention to the correct brushing method: brush vertically along the teeth, first brush the inside and then brush the outside. Don't brush back and forth horizontally, or you will damage your gums.
2. Pay attention to oral hygiene and protect your teeth. Eat less candy at ordinary times. Especially don't eat sugar before going to bed to prevent dental caries. In addition, we should pay attention to the usual hygiene habits, do not bite fingers, do not bite pencils and other foreign bodies, and do not lick your teeth with your tongue.
3. If your teeth are sick, you should seek medical advice in time. If there are cavities, they should be repaired or pulled out.
It is not difficult to achieve the above points, the key is perseverance. May all students have healthy and beautiful teeth.
Good oral health care is not the only way to have healthy and beautiful teeth. Eating habits also play an important role. Here are some suggestions to help you have a beautiful smile!
Your teeth: the main sign of health and beauty
Teeth enable us to enjoy all kinds of food! Healthy teeth can make us chew hard food, meat, raw food and fruit without scruple ... Good chewing can strengthen the strength of gums and promote saliva secretion. They participate in the digestive process and play a bactericidal role in teeth. In addition to genetic factors, the color and hardness of our teeth also depend on dental care and eating habits.
Keep your teeth healthy: a balanced diet!
A balanced diet and proper dietary distribution throughout the day (in order to avoid snacks, four meals a day: breakfast, lunch, dinner and snacks) are very beneficial to strong teeth. In fact, it helps our teeth to better resist stimulation: enamel erosion, dental caries ... Fresh food, such as carrots, carrots or apples, rubs on the surface of teeth when chewing, which actually plays a role in cleaning teeth. In addition, lipids, some protein (casein of cheese), minerals (phosphorus, calcium, fluorine ...) and vitamin D have antibacterial effects, which limit the discharge of inorganic salts in enamel.
On the contrary, snacks, especially those "soft" foods, carbohydrate foods (candy or sweet drinks, bread, cakes, etc. ) or acidic foods (soda, fruit, juice) usually increase the risk of dental caries. Sugar can be converted into acid, which may destroy the enamel on the tooth surface. If possible, clean your teeth carefully after every meal. If you don't have the conditions, you can also rinse your mouth seriously or chew a piece of sugar-free gum. In fact, any increase in saliva flow will reduce the risk of dental caries. It should be pointed out that excessive drinking of coffee, tea and smoking may make teeth yellow.
Four dairy products make teeth stronger.
They are the best sources of calcium and phosphorus we need, and also the main minerals of tooth enamel and root supporting bone. Mineralization of deciduous teeth began in the fourth month of pregnancy, and mineralization of stone teeth began in the first year of birth. After the teeth are formed, the enamel is renewed and maintained. We should drink milk, and it is better not to drink sweet drinks. Dairy products (yogurt, etc. ) Also bring calcium, phosphorus and vitamin D, which will increase the absorption of calcium and phosphorus. Finally, the main protein casein in milk can limit the excessive discharge of inorganic salts in enamel. People in the past did a good job: they usually ate cheese after dessert and reduced the acid secreted by carbohydrates with the help of casein and lipids in milk.
Drink more mineral water, which is a natural source of fluorine.
Natural mineral water meets the human body's demand for fluorine. Fluorine can increase the enamel of teeth, strengthen teeth and protect teeth from microbial erosion. Most mineral water contains 0.3 mg of fluorine per liter, but some are as high as 8 mg per liter. We can also see fluoride on the dining table. For pregnant women and children, there are also tablets made of fluorine (0.5 mg to 1 mg according to age). Tea, sea fish and some vegetables (spinach, carrots, etc.) also contain fluorine. However, excessive intake of fluoride (more than 2 mg per day) may make teeth black.
Use chocolate and sugar-free chewing gum