After entering old age, the condition of the teeth and other organs tend to age in terms of structure and function. As the gateway to the digestive system, the mouth plays an important role. Nutrient-rich foods need to be chewed by the teeth to be easily absorbed. After the human body obtains nutrients, it can improve health, overcome diseases, and prolong life. However, once there is tooth loss or damage, many health problems will arise. Tooth loss affects digestive function. Chewing food in the mouth promotes the secretion of digestive juices. After tooth loss, the food cannot be chewed sufficiently, leading to swallowing without proper digestion, reduced gastric juice secretion, and slowed gastrointestinal peristalsis, thereby increasing the burden on the gastrointestinal tract, causing diseases, and affecting food intake and nutrient absorption. Tooth loss affects facial shape and pronunciation. The existence of the dental arch maintains the appearance of the face, especially the lower one-third, while the canines support the corners of the mouth, ensuring facial fullness. Once there is damage, the lips and cheeks will lose support, becoming flat and collapsed, with deepened nasolabial folds, shortened lower one-third distance of the face, increased wrinkles, and a more aged appearance. Pronunciation is produced under the coordination of airflow, tongue, and teeth. Therefore, once there is tooth loss, clear expression becomes difficult. Tooth loss affects mental health. Because of the aged appearance and unclear pronunciation, the elderly may experience significant feelings of frustration. Combined with discomfort in the digestive system, these changes will directly affect the physical and mental health of the elderly and accelerate aging. Tooth loss affects the lifespan of surrounding healthy teeth. After tooth extraction without restoration, it leads to alveolar bone loss and atrophy, causing a decrease in the height of the jawbone and eventually resulting in the loss of other healthy teeth.