Gum recession at 45 years of age is generally pathologic recession of the gums, and the etiology may include periodontitis, improper brushing, and orthodontic and bite forces. Although age-related gingival recession exists, for 45 years of age, it is generally due to pathologic recession of the gums. The possible etiologies are as follows: 1. Periodontitis can lead to resorption of the alveolar bone and loss of support for the gums, resulting in recession. 2. Brushing too hard, with toothbrush bristles that are too hard or horizontally, may lead to recession of the gums. 3. During orthodontic movement, or when there is occlusal trauma, when the teeth are subjected to too much force, the teeth are prone to gum recession where the alveolar bone is thin. If gum recession occurs at the age of 45, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.