Recently, when Ms. Fang looked at the mirror, she unintentionally found that the surface of her left lower jaw back tooth was a bit dark, but she did not feel uncomfortable about it. The doctor told Ms. Fang that she was lucky that she found it early, if she came late, the affected tooth formed a cavity or had painful symptoms, it would be very troublesome to treat. The doctor explained to Ms. Fang in detail the causes and hazards of caries, in fact, “caries” is the most common oral disease, its causes are many, in simple terms, after eating, due to not timely or effective oral cleaning, some food, especially the food with high sugar content and sticky, remains on the teeth surface, and some bacteria in the mouth use these food residues to get nutrition and produce a lot of acidic substances to erode our teeth. The early stage of caries is usually only the change of tooth color, which is hard for patients to find out by themselves, and often need professional doctor’s examination to confirm the diagnosis. However, if the caries is not treated in time at the early stage, it will continue to develop and form cavities, and when the food residue falls into the cavity when eating, the patient will have a “transient” pain or even spontaneous pain, so the best time for treatment is often missed! So how to detect caries in early stage and get timely treatment? The stomatologist suggests that you should visit the stomatology department every six months to a year to have a comprehensive oral examination, so that the caries can be treated at the early stage. In the early stage of caries, the treatment is relatively simple and the treatment effect is good, the treatment is to remove the decayed tooth tissue with professional oral instruments and then fill the cavity with professional dental materials to restore the physiological form and normal chewing function of teeth. When the scope of decay becomes bigger and bigger, forming deep cavity, even involving to the pulp tissue, appearing pulpitis or even periapical inflammation, usually rely on simple filling can not solve the problem, need to do other treatment, the treatment is relatively complicated, the effect is not ideal, and even have the risk of tooth extraction. Therefore, once tooth decay is found, you should come to hospital for treatment as soon as possible. How can we pay attention to prevent the occurrence of caries in daily life? First of all, we should do a good job of oral hygiene every day, brush teeth three times a day, insist on three minutes each time, master the correct brushing method, and clean every tooth surface in place; secondly, we should develop good eating habits, try to eat less food with high sugar content and sticky, and drink less drinks, especially carbonated drinks; furthermore, people who are susceptible to caries should go to the hospital regularly to receive fluoride anti-caries treatment, etc.