Teeth are an important part of our mouth and jaw system, and they are responsible for the important functions of chewing, swallowing, speech, expression and breathing, and they are also closely related to the beauty of our face, psychological state and mental factors. There may be some misconceptions about “missing teeth”, so what exactly does “missing teeth” mean? People with different educational backgrounds and different professions have different interpretations of missing teeth. In the field of dentistry, a tooth is a whole including the crown and the root. The part of a tooth exposed in the mouth is called the crown, the part buried in the jawbone is called the root, and the part between the crown and the root is called the cervical part of the tooth. Although our teeth are hard, there are many reasons why they can be broken and missing. However, in the eyes of the general public, a tooth is considered missing as long as the crown is gone. Therefore, what the average reader calls missing teeth may include the following cases: 1. complete or most of the crown is missing, with the root still present; 2. single tooth is missing; 3. multiple teeth are missing; 4. the whole mouth is missing. In order to facilitate consultation and consultation, it is important to state the condition accurately and understand the meaning of the diagnosis. The reader has in mind the following diagnosis for each of the above cases of missing teeth in the dental clinic: 1, “the crown is completely or mostly missing and the root is still present”, which is diagnosed in the dental clinic as “severe tooth loss” or “residual crown, residual root”; 2, “missing tooth”; 3, “missing tooth”; 4, “missing tooth”; 5, “missing tooth”; 6, “missing tooth”; 7, “missing tooth”. 2. “Single missing tooth” or “multiple missing teeth”, which is diagnosed as “tooth loss” in the dental clinic; 3. 3. “Total tooth loss”, diagnosed as “missing teeth” in the dental clinic.