Definition of sixth age teeth. When a child reaches 6 years of age, the tooth that erupts at the end of the dental row, i.e. behind the second molar, is the first permanent molar, the embryonic first permanent molar begins to form around 3-4 months of age, calcification begins at birth, crown calcification is completed around 2-3 years of age, and erupts in the mouth at 6-7 years of age, one on each side, so it is customarily called “sixth age Because it erupts around 6 years old, it is customarily called “six-year-old teeth”. The role of the sixth age teeth in the oral cavity. It is the earliest permanent tooth to erupt and will be with you for the rest of your life, it plays a very important role in the mouth. The sixth tooth is the strongest of the permanent teeth. It has the largest crown, the most cusps, and the widest chewing area, and is responsible for more biting forces and chewing functions than other permanent teeth. It is particularly strong because of the large angle of bifurcation of its roots. It is located in the middle of the entire dental arch and becomes the main pillar of the dental arch, which is important for maintaining the normal alignment of the upper and lower jaw teeth, maintaining the correct occlusal relationship and ensuring the normal development of the jaw and face. The importance of six-year-old teeth. 1. Non-replaceable. The “sixth-aged teeth” are the four large teeth that erupt around the age of 6, which are medically called the “first permanent molars” (teeth that accompany the whole life). It is the first molar to erupt, and many parents mistake it as “milk tooth, think it can be replaced”, so they do not pay attention to its decay and do not actively treat it, resulting in serious decay and early loss. 2.Keep the normal facial development. The sixth age tooth is the strongest one in the permanent tooth series. It has the largest crown, the most cusps, the widest chewing area, and the biting force and chewing function are bigger than other permanent teeth. It is particularly strong because of the large angle of bifurcation of its roots. Sixth-aged teeth are located in the middle of the entire dental arch and become the main pillar of the dental arch, which is important for maintaining the normal alignment of the upper and lower jaw teeth, maintaining the correct occlusal relationship and ensuring the normal development of the jaw and face. 3. The strongest chewing ability. After the eruption of the sixth age teeth, these four largest teeth will accompany us for the rest of our lives, and their functions are extremely important and belong to the “hard-working” teeth. Firstly, it is the largest tooth in the occlusal surface area, like a stone mill, which plays a great role in grinding food; secondly, it is subject to the greatest chewing pressure. At the same time, it has many cusps and many sockets between cusps and cusps, and it is deep and narrow, so it is easy to hide dirt and stains, occurring caries (rotten teeth) and even causing premature loss. 4.It is easy to occur tooth decay and induce systemic diseases. Children’s oral disease is mainly caries, the caries rate of 12-year-old permanent teeth is 29%, and 60% of the caries occurs in the first permanent molar (i.e. six-age teeth). Once the sixth-aged teeth are decayed, it not only causes pain, but also affects appetite, chewing and digestive function, which adversely affects the growth and development of children. If tooth decay is not treated in time, it will also lead to pulpitis, alveolar abscess, jaw bone osteomyelitis, etc. In serious cases, it will also induce rheumatoid arthritis, heart disease, nephritis, endocarditis and other systemic diseases. The danger of necrosis of sixth-age teeth. Because there is no loss of milk teeth when the sixth age teeth erupt, it is easy for parents to ignore the decay of the milk teeth that have to be replaced, which can cause the loss or extraction to become permanent missing teeth, and its early loss will not only greatly reduce the chewing function of children and cause malnutrition, but also affect the development of jaw bone and cause the inclination of neighboring teeth and the elongation of jaw teeth to cause the disorder of bite relationship, which has a very negative impact on the physical and mental health of children. It has a negative impact on the physical and mental health of children. Because the first permanent molar eruption is the earliest, the mineralization degree is poor, and the sulcus of the joint surface is deep, it is easier to get caries, and the caries progresses quickly, when the sixth age teeth erupt and the caries has not yet occurred, we can take preventive measures in hospital, and the common method is sulcus closure method. It is very necessary to maintain good oral hygiene and regular oral examination. When brushing the teeth, focus on brushing the lifting and cheek surfaces of the six-year-old teeth. Some caries can only be found with the help of oral apparatus, and timely filling and early treatment can help the health of teeth. The special significance of the sixth age teeth for children is manifested in three aspects: firstly, it is the earliest permanent tooth to erupt, which will accompany us for a lifetime with its superb chewing function and biting force and play its chewing function; secondly, the sixth age teeth have a positioning role for the eruption and arrangement of other permanent teeth of children; finally, it has an important influence on whether children’s teeth can bite together normally and the normal development of upper and lower jaws and face.