Gums have receded, resulting in gaps between teeth that are not retractable. Gum recession refers to the recession of the gums in the supporting tissues (periodontal tissues) around the roots of the teeth, exposing the roots. Gum recession can lead to gaps between the teeth. These gaps are spaces given up by soft tissue recession, and there is no substantial damage to the tooth, so there is no way to retract them. This condition can lead to wider and wider gaps if gum recession is not treated in a timely manner. The main causes of gum recession are periodontal disease and localized trauma. Gum recession is usually accompanied by resorption of the alveolar bone, which can lead to loose, shifting or even loss of teeth. If gum recession is suspected, you should go to the hospital for examination and take appropriate treatment or health care measures according to the doctor’s advice. Therefore, as the gap between teeth cannot be retrieved due to gum recession, patients should protect their teeth, pay attention to keeping teeth clean and hygienic, and have regular oral checkups.