With increasing age, the elderly body will experience many changes (ageing changes), such as gradual aging of the body, degeneration of organ functions, decreased resistance to diseases, etc.. These will also cause obvious changes in the oral tissues of the elderly: for example, enamel wear on the biting surface of teeth; dentin elasticity decreases and brittleness increases; pulp cavity calcification becomes smaller, pulp tissue degeneration and atrophy; tooth neck exposure and wear; alveolar bone resorption, gum atrophy and root exposure; saliva secretion decreases, oral mucosa is dry and elasticity decreases. These are the factors that lead to the increase of the incidence of caries and periodontal disease in the elderly. But this does not mean that oral health care for the elderly is useless. And it is very necessary to understand this physiological change, adjust the mentality and strengthen oral health care with optimistic and positive attitude to promote the whole body health. The root surface of the teeth of the elderly is the site of good caries. Due to the gingival atrophy, the contact part of the adjacent teeth turns from point to surface to make the contact relaxed, so that the gap between teeth is easy to occur food embedment, accumulation of plaque, not easy to remove and lead to the occurrence of root surface caries, accompanied by periodontal disease, which is the main cause of tooth loss of the elderly. Many elderly people have developed incorrect brushing method, which not only can’t achieve the effect of cleaning teeth, but also can cause damage to periodontal, therefore, we should remind the elderly people to correct the wrong brushing method for the sake of health. The correct method of brushing is to use the vertical rotation method of brushing, using the horizontal sawing method of brushing is wrong. In addition, people who wear dentures should focus more on cleaning the tooth surface of the carabiner area. For those with exposed root surfaces, it is important that the bristles of the toothbrush are not too hard, generally medium hardness is sufficient. In order to effectively remove plaque from the adjacent surface of the teeth, you can use oral hygiene aids such as interdental brushes, dental floss and toothpicks. For those who wear dentures, they should also pay attention to the cleaning of dentures. Emphasize that it is necessary to go to the hospital for oral examination regularly if available. Once the problem is found, it should be dealt with as early as possible so that minor problems do not drag out into major problems, making it more difficult to treat and increasing the financial burden on yourself. Pulp cavity calcification becomes smaller, pulp tissue degeneration, atrophy; tooth neck exposure, wear; alveolar bone resorption, gum atrophy, root exposure; saliva secretion decreases, oral mucosa dry, elasticity decreases. These are the factors that lead to the increase of the incidence of caries and periodontal disease in the elderly. But this does not mean that oral health care for the elderly is useless. And it is very necessary to understand this physiological change, adjust the mentality and strengthen the oral health care with optimistic and positive attitude in order to promote the whole body health. The root surface of the teeth of the elderly is the site of good caries. Due to the gingival atrophy, the contact part of the adjacent teeth turns from point to surface to make the contact relaxed, so that the gap between teeth is easy to occur food embedment, accumulation of plaque, not easy to remove and lead to the occurrence of root surface caries, accompanied by periodontal disease, which is the main cause of tooth loss of the elderly. Many elderly people have developed incorrect brushing method, which not only can’t achieve the effect of cleaning teeth, but also can cause damage to periodontal, therefore, we should remind the elderly people to correct the wrong brushing method for the sake of health. The correct method of brushing is to use the vertical rotation method of brushing, using the horizontal sawing method of brushing is wrong. In addition, people who wear dentures should focus more on cleaning the tooth surface of the carabiner area. For those with exposed root surfaces, it is important that the bristles of the toothbrush are not too hard, generally medium hardness is sufficient. In order to effectively remove plaque from the adjacent surface of the teeth, you can use oral hygiene aids such as interdental brushes, dental floss and toothpicks. For those who wear dentures, they should also pay attention to the cleaning of dentures. Emphasize that it is necessary to go to the hospital for oral examination regularly if available. Once the problem is found, it should be dealt with early, so as not to delay the small problem into a big problem, which makes the treatment more difficult and adds to your financial burden.