First, it affects the digestive function. Food is chewed in the mouth to promote the secretion of digestive juices. And when there are dental diseases and missing teeth, can not fully chew, swallowing, gastric juice secretion is reduced, gastrointestinal peristalsis slowed down, thus increasing the burden on the gastrointestinal tract, leading to disease, affecting the intake of food and nutrient absorption. Secondly, it affects the face shape and pronunciation. Diseases and defects of the anterior teeth will directly affect the patient’s cosmetic dental arch exists to maintain the performance of the face, especially the lower 1/3, and the cuspids support the corners of the mouth to ensure the fullness of the face. Once defective, the lips and cheeks will lose support and deflate and collapse, the nasolabial folds will deepen, the distance of the lower 1/3 of the face will shorten, wrinkles will increase, and the face will look older. And the pronunciation is produced by the airflow with the cooperation of tongue and teeth, so once the teeth are missing, it cannot be expressed clearly. Thirdly, the missing teeth can cause the adjacent missing teeth to tilt and shift to the missing area, so that the surviving teeth lose the normal adjacent relationship, causing food embedding, and then secondary to caries and periodontal disease; missing teeth can cause the elongation of the opposite jaw teeth, causing misalignment of bite, and serious cases can cause temporomandibular joint disease; fourthly, it affects the mental health. Because of the pale face and ambiguous pronunciation, many elderly people will have a great sense of psychological frustration, coupled with the discomfort of the digestive system, these changes will directly affect the physical and mental health of the elderly and accelerate aging.