Many first-time orthodontic patients, the most common question is whether orthodontics will cause the teeth to become loose and reduce the service life of teeth, in fact, orthodontic treatment is a kind of tooth movement in the physiological range, except for a very small number of patients with special physical characteristics will cause obvious root resorption due to treatment, will not have a significant impact on dental health, temporary loosening of teeth in the treatment process is inevitable and normal, treatment will be completed The temporary loosening of teeth during treatment is inevitable and normal, and will disappear naturally after treatment is completed. However, orthodontic treatment increases the burden on teeth and makes oral cleaning more difficult due to the presence of orthodontic attachments. If oral hygiene is not maintained well, it will promote and aggravate gingivitis and periodontitis, or secondary dental caries. If oral hygiene is not maintained properly, it will have irreversible effects on dental health. Some patients are hesitant to have orthodontic extractions because they are concerned about the adverse effects of a reduced number of teeth or the inability to close the extraction gap. In fact, many malocclusions occur because the jawbone cannot accommodate the existing teeth. Tooth extraction is to create a gap to align the teeth, adjust the occlusal relationship, and recover the protruding teeth to improve the lateral appearance, in order to achieve aesthetic and functional perfection, which is beneficial to oral health and does not leave a gap.