In hospitals and dental clinics, we often encounter patients who do not understand the importance of taking radiographs before extraction (especially in older patients), and always believe that the radiographs are a disguised increase in fees and medical costs. Is this really the case? Why do doctors recommend that we have a radiograph? What problems can be solved by taking them? In fact, the role of radiographs is very important. From small dental films to large surface tomography films and even CT films, their role cannot be ignored. Through these imaging examinations, we can learn: 1, the direction of tooth growth, the number of roots, whether the roots are curved, whether there is expansion, whether there is a lesion at the apical part of the root and the size of the lesion; 2, the maxillary molar we need to know its relationship with the maxillary sinus, and the mandibular molar we need to know its relationship with the mandibular canal; 3, whether there are rational volar teeth, multiple teeth, cysts, etc. in the jawbone: 4, children in the mixed dental row The relationship between the permanent tooth germ and the milk tooth in the period. In addition, the imaging examination is also an important basis to determine whether the disease is healed or not. In short, the film has an important role for the dentist to diagnose the dental disease, design the treatment plan, take treatment measures and judge the healing situation. Diagnosis is the first and the most critical step in the treatment of any disease, and radiographs are an important tool to assist in the diagnosis. Therefore, I hope you will ask more questions before your next extraction: “How is my condition? Is it possible to keep the tooth? What should I do after the tooth is extracted?” instead of “What is the purpose of taking an X-ray for a tooth extraction? When you ask me a question online, it is better to attach a clear picture, so that I can have a better understanding of your condition and provide you with better service.