1. write a composition with teeth
teeth
I am a tooth, born in the mouth of a little girl. I am really glad that my master is a little girl who loves cleanliness very much. She brushes her teeth every morning and evening, making my body shiny and flawless, which makes me win enough face in front of my partners. Although I am young, I have tasted the joys and sorrows of the world.
in my opinion, the young master has a big shortcoming, that is, he likes to eat sour food. The young master's taste is very special, and he loves sour food, such as oranges and hawthorn, and almost all the sour food in the world is in his mouth. I'm in great trouble. Every time I get so sore that I feel weak all over, it takes a lot of effort to bite something else. Alas! However, in order to satisfy my young master, I have to submit to humiliation.
The young master, like other children, has a soft spot for sweetness. Sweet biscuits, sweet plums ... She can't live without them every day. It can be said that without sweets, it wouldn't be a day for her. Every time the young host eats sweets, the Chinese website (Thn21) creates original works. Just like a fireman, I picked up my toothbrush and rubbed it on my body with delicious toothpaste. Numerous small bubbles circled around my body, and it felt very comfortable. Therefore, no matter how many sweets the young master eats, it won't hurt my health.
speaking of bitterness, I have tasted a lot. Whenever the young master is ill, he always takes a lot of medicine. As the saying goes, "Good medicine tastes bitter". But for the sake of the young master, I can only hold back and act as a "hero to save the United States".
The young master prefers spicy food. No matter what he eats, he likes to sprinkle a lot of spicy powder. It always makes me tremble with spicy food. But for the sake of my health, the young master is still very temperate.
Looking at my white body, I am really proud of my little master. Ah, I am so lucky to have such a good host. 2. Write a composition on the topic of Tooth
The Five Senses
Every one of us carries the five senses at any time and place and never leaves. The five senses on a head all have different postures and different personalities.
The position of the nose on the face is really unique. He lives in the center of the whole face, with eyebrows, eyes and mouth to protect him for 24 hours. Just like the emperor, he enjoys a carefree life. However, as an important organ of the five senses, the nose also risks its life. He had to endure the stench in toilets and sewers for a long time, and the suffocating smell emitted by disinfectant and waste gas discharged from factories was only absorbed by him alone. He needs to identify whether the food has gone bad. Natural and man-made disasters often hit him, just say the most common cold! Almost without exception, a cold will have symptoms such as stuffy nose and runny nose, and it is nothing more than the nose that suffers.
the mouth is under the nose. The contribution of the mouth is self-evident. It can make you taste the delicious food in the world and express your feelings in words. However, I think that the mouth is not born to enjoy life. Although the food is always tasted by him first, the words are always expressed by him. However, from the words "illness comes from the mouth, disaster comes from the mouth", we can understand the helplessness of the mouth. The mouth has to bear a lot of accidents, for example, if any part of the body is unwell, it is up to him to taste the bitter pill.
Although the nose is prominent and the mouth tastes delicious, God did not give people the most important role when he created them, just like how can you have your cake and eat it?
The most important thing in a person's face is the eyes. As others say, the eyes are the windows to the soul. We can see the beautiful world outside through him, and others can feel our hearts through him. I can't imagine what kind of disaster his disappearance will bring us.
Seeing all the way and listening to all directions, it can be seen that the importance of ears is second only to eyes. Sweet and elegant music rushes into our lives through ears, which gives people spiritual comfort after a meal. Ear is also the only place in the five senses where a beautiful lady chooses to wear jewelry, but beauty comes at a price. Putting holes in the ears and hanging earrings can really make the five senses look more beautiful, but the pain when piercing will make the ears very painful.
Bro with eyebrows is the smallest and most inconspicuous of the five senses, and his position is also the lowest among the five senses. At best, his function is to draw thrush and make the five senses look more beautiful, that's all.
I only think that the five senses on the face are different in function and status, and they are neither beautiful nor ugly nor noble. They live on people's heads, enjoy the supreme position and control the normal work of their limbs. They have their own strengths and weaknesses.
not bad, I hope you can adopt it. 3. Write a composition on observing teeth
In the human body, teeth have grown twice in one's life, and the first ones are called "deciduous teeth", and by the age of two, there are twenty * * *. Around the age of six, deciduous teeth gradually fall off and grow "permanent teeth", * * * 32. According to the shape, it can be divided into incisors, fangs and molars. The function of incisors is to cut off food, bicuspids are used to mash food, and molars can grind food.
From the appearance of a tooth, a tooth consists of three parts: a crown, a root and a neck.
A crown is the part of the outer layer of a tooth that is covered by enamel, and it is also the main part of the chewing function. Under normal circumstances, most of the crown is exposed in the mouth, which is called a clinical crown. The part we can usually see in the mouth is the crown. Dental crowns have different shapes according to their chewing function.
The root is the part of the outer layer of the tooth covered by cementum, and it is also the supporting part of the tooth. Some teeth are single teeth, some are multiple teeth, and the tip of each root is called root tip; Each root tip has a small hole that passes through the blood vessels and nerves of the pulp, which is called the apical foramen; Under normal circumstances, the root of the tooth is completely embedded in the alveolar bone and fixed by the alveolar fossa. Morphology and number also vary with different functions, which can be divided into single tooth and multiple teeth. Most incisors and fangs are one root. A few mandibular premolars have two roots and most of them have one root. Most maxillary premolars have two roots, and a few have one root. Generally, molars have 2-3 roots. There is a small hole at the end of each root, which is called apical foramen.
The junction of crown and root presents an arc curve, which is called the tooth neck, also known as the neck edge or neck line.
from the longitudinal section of the tooth, the tooth body is composed of enamel, cementum, dentin and pulp.
enamel, commonly known as enamel, is the surface layer of the crown, which is translucent white hard tissue and the hardest tissue with high calcification. Its hardness is second only to that of diamond. Recent research shows that enamel is a natural nano-material. Fully hardened enamel contains only 4% organic matter, while inorganic matter can reach as high as 96%. Generally speaking, it is a living tissue without feeling and its metabolic process is slow.
Dentin is the main part of the tooth, which is located in the inner layer of enamel and cementum, and is also the side wall of pulp cavity and root canal. It is yellowish in color, containing about 3% organic matter and water and 7% inorganic matter, and its hardness is lower than that of enamel. If observed with a microscope, we can see that there are many small tubules in the dentin, which are called dentin tubules. There are nerve fibers in the tubules. When the dentin is exposed, it can feel the cold, hot, sour and sweet outside, causing pain. There is a cavity in it called pulp cavity.
cementum is a yellow hard tissue that constitutes the surface layer of root. It wraps around the outer layer of the root, is thin and yellow, contains about 45%-5% inorganic matter, has hardness similar to that of bone tissue, and has the characteristics of continuous regeneration.
Dental pulp is a honeycomb tissue filled in dental pulp cavity and root canal, which contains blood vessels, nerves and lymph. It is mainly composed of connective tissue, blood vessels and nerves, and the latter two are connected with the blood circulation system and nervous system of the body through apical foramen. The function of dental pulp tissue is to form dentin, which has the ability of nutrition, sensation and defense. The pulp nerve is particularly sensitive to external * * *, which can produce unbearable and severe pain. It is the only soft tissue in tooth tissue.
Periodontal tissue structure
Periodontal tissue is composed of periodontal ligament, alveolar bone and gum (commonly known as tooth flower meat). Its main function is to support, fix and nourish teeth.
Periodontal membrane: a dense fibrous tissue, one end of which is embedded in cementum and the other end is connected with alveolar bone. In fact, the teeth are suspended in the alveolar fossa through periodontal membrane, so that the teeth can be firmly fixed in the alveolar fossa of the jaw, which has certain elasticity and is beneficial to buffering the chewing force borne by the teeth.
alveolar bone: It surrounds the protruding part of the jaw around the root, forming an alveolar fossa, in which the root stands upright, so that the teeth and alveolar bone are tightly connected, not loose, and easy to chew.
Gum: It covers the surface of alveolar bone, wraps around the neck of teeth, and the edge is arc-shaped. The gum between two teeth is wedge-shaped, which is called gum. Normal gums are pink, tough and slightly elastic, so they can chew pressure and tolerate food friction.
The nerves and blood vessels of dental pulp are connected with those of alveolar bone and periodontal ligament through apical foramen. Nutrients are supplied to dental pulp through blood to nourish teeth, so teeth are closely related to periodontal tissue. 4. Write a composition to protect teeth.
To protect teeth, we must first understand the structure of teeth. Teeth are the hardest organs in the human body. They have the functions of biting, tearing, grinding food and assisting pronunciation. There are two pairs of teeth in a person's life: one is deciduous teeth, 2 are * * *, and 1 are upper and lower jaws. They begin to sprout at about half a year after birth and come out at about two and a half years old. The other pair is permanent teeth, ***32, with 16 upper and lower jaws respectively. Since the age of 6, deciduous teeth have been gradually replaced, and all permanent teeth erupt around the age of 12 except the third molar, which usually erupts after the age of 2, also known as wisdom teeth. Wisdom teeth can last for life, so 28~32 permanent teeth are normal. Teeth are divided into crown, neck 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 Shi Ying. The root of the tooth is embedded in the alveolar process of the upper and lower jaws. The surface of the root is covered with a layer of cementum. The neck of the tooth is a slightly thin part between the crown and the root, which covers the gums. The tooth is mainly composed of dentin, and the internal cavity is called the tooth cavity. The living tooth cavity is filled with connective tissue, nerves and blood vessels. Together, it is called pulp. Blood vessels and nerves enter and exit from the apical foramen of teeth. When suffering from dental caries, when bacteria corrode enamel and dentin and enter the pulp cavity, the pain is unbearable. (See Figure 37) Students should protect their teeth and do the following: 1. Develop a good habit of brushing their teeth. Rinse your mouth with warm water after meals and brush your teeth once in the morning and evening. Too many times of brushing your teeth will damage your teeth. [14]? Back to the mother pepper m: nuclear spoon rebellion? Pan ⅲ? ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ ⑼ 934 What about Li Fu? 2. Pay attention to dental hygiene and protect your teeth. Eat less candy at ordinary times, especially before going to bed, to prevent dental caries. In addition, pay attention to your usual hygiene habits, do not bite your fingers, do not bite foreign objects such as pencils, and do not lick your teeth with your tongue. 3. If your teeth are sick, you should seek medical advice in time. In case of decayed teeth, you should repair or pull them out. It is not difficult to do the above. The key is to persevere. 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 symbol of health and beauty. Teeth enable us to enjoy a variety of foods! 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, and they participate in the digestion process, which has a bactericidal effect on teeth. In addition to genetic factors, the color and hardness of our teeth also depend on dental health care and eating habits. To keep teeth healthy: a balanced diet! A balanced diet and proper distribution of meals in a day (in order to avoid eating snacks, four meals should be arranged in a day: breakfast, lunch, dinner and snacks) are very beneficial to strong teeth. In fact, it is beneficial to our teeth to better resist enamel erosion, dental caries ... fresh foods, such as carrots, red radish or apples, rub on the tooth surface when they are chewed. 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 ...) or acidic foods (soda water, fruits, juices), usually increase dental caries. Acid may destroy the enamel on the surface of teeth. If possible, clean your teeth carefully after eating food every time. If there is no condition, you can also rinse your mouth seriously or chew a piece of sugar-free gum. In fact, Any increase in saliva flow reduces the risk of dental caries. It should be pointed out that excessive drinking of coffee, tea and smoking may make teeth yellow. Four kinds of dairy products make teeth stronger. They are the best sources of calcium and phosphorus we need, the main mineral materials for tooth enamel and root supporting bone. Mineralization of deciduous teeth begins in the fourth month of pregnancy, and mineralization of stone teeth begins in the first year of birth. After tooth formation, Enamel is renewed and maintained all the time. 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, casein, the main protein in milk, can limit the excessive discharge of inorganic salts in tooth enamel. In the past, people did a good job: they usually ate cheese after dessert, and with the help of the restriction of casein and the lipids in milk, Reduce the acid secreted by carbohydrates. Drink more mineral water, which is the natural source of fluorine. Natural mineral water meets the human demand for fluorine. Fluorine can increase the enamel of teeth, strengthen teeth and protect teeth from microbial erosion. Most mineral water contains .3 mg of fluorine per liter, but some of them contain as much as 8 mg per liter. We can also see fluoride salts on the dining table. For pregnant women and children, there are tablets made of fluorine (according to age, .5 mg to 1 mg). Fluoride is also contained in tea, sea fish and some vegetables (spinach, red radish, etc.). However, excessive intake of fluoride (more than 2 mg per day) may make teeth black. Taking advantage of chocolate and sugar-free chewing gum, in fact, cocoa contains tannic acid, fluoride and calcium phosphate. These three substances are all involved in protecting teeth. In "sugar-free" chewing gum, But it doesn't cause dental caries: xylitol plays a bactericidal role, which helps to reduce dental plaque, and sorbitol (sugar synthesized from glucose or fructose is used as artificial sweetener). Therefore, a 2.2-gram sugar-coated chewing gum only contains 3.8 calories. 5. Writing about teeth < P