Just as trees need soil to grow, teeth need a certain environment to grow, namely periodontal tissue, which includes gums, periodontium, alveolar bone and bone. Periodontal disease is a disease that occurs in the periodontal tissues, including lesions involving the superficial gum or the deeper periodontal tissues (periodontium, alveolar bone and bone). Periodontal disease is a common oral disease and one of the main causes of tooth loss in adults, as well as a major oral disease that endangers human teeth and general health. Etiology 1. Local factors (1) Plaque is a microbial group that adheres to the tooth surface and cannot be removed by mouth rinsing or water rinsing. It has been recognized that plaque is the initiating factor of periodontal disease and is the main pathogenic factor causing periodontal disease. (2) Tartar is the mineralized plaque deposited on the tooth surface. Tartar is also divided into supragingival tartar and subgingival tartar according to its deposition site and nature. Supragingival tartar is located on the tooth surface above the gingival margin and can be seen directly by the naked eye. It is deposited more frequently in the cervical region of the teeth, especially in the areas opposite the openings of the large salivary ducts, such as the buccal side of the maxillary molars and the lingual side of the mandibular anterior teeth. Subgingival tartar is located on the root surface below the gingival margin, in the gingival pocket or in the periodontal pocket, and cannot be seen directly by the naked eye; it must be probed with a probe to know the deposition site and the amount of deposition. Subgingival tartar can be formed on any tooth, but is more frequent on the adjacent and lingual surfaces. Tartar is harmful to periodontal tissues, mainly because it constitutes a good environment for plaque attachment and bacterial growth. The tartar itself hinders the maintenance of oral hygiene, thus accelerating the formation of plaque and creating irritation to the gingival tissue. (3) Traumatic occlusion is called traumatic occlusion if the occlusal force is too large or the direction is abnormal, which exceeds the joint force that periodontal tissues can withstand, resulting in damage to periodontal tissues. Traumatic occlusion includes early contact during occlusion, dental interference, nocturnal teeth grinding, etc. (4) Other factors including food embedding, poor restorations, mouth breathing, etc. also contribute to the inflammatory process of periodontal tissues. (2) Systemic factors Systemic factors are promoters in the development of periodontal disease. Systemic factors can reduce or change the resistance of periodontal tissues to external stimuli, making them susceptible to disease, and can promote the development of gingivitis and periodontitis. (1) Endocrine disorders? Such as abnormal secretion of sex hormones, adrenocorticotropic hormones, thyroxine, etc. In particular, many reports have confirmed that diabetes and periodontal disease can interact with each other. (2) Dietary and nutritional aspects? There can be vitamin C deficiency, vitamin D and calcium and phosphorus deficiency or imbalance, malnutrition, etc. (3) The relationship between blood disorders and periodontal tissue is extremely close? Patients with leukemia often have swollen gums, ulcers, bleeding, etc. (4) The long-term use of certain drugs? such as phenytoin sodium can cause fibrous hyperplasia of the gums. Clinical manifestations (1) Gingivitis: The main clinical manifestations are gingival inflammation, bleeding, (2) Periodontitis: In addition to gingival inflammation, there is periodontal pocket formation and alveolar bone resorption in the early stage, and there can be mild chewing weakness at this time, and in the late stage, after deep periodontal pocket formation, the height of alveolar bone is reduced, teeth are loosened and shifted significantly, and acute periodontal abscess can be accompanied, and in severe cases, teeth can fall out by themselves or lead to tooth extraction. Other symptoms include tooth pain, bad breath and other complications. The treatment of periodontitis is based on both the elimination of the cause and the reduction of symptoms. (1) For example, scaling, scraping, root planing, etc. (2) Review the efficacy 1-2 months after basic periodontal treatment, if periodontal pocket ≥ 5mm then periodontal surgery is required, if periodontal pocket ≤ 5mm then maintain oral hygiene and review every 3 months. (3) Fixation of loose teeth in periodontal splints and jaw adjustment to establish a balanced jaw relationship. (At present, periodontal splints are usually used clinically to fix loose teeth, disperse dental forces and improve the patient’s chewing function, which connects multiple loose teeth together or fixes loose teeth on healthy teeth to make them new chewing units.) (4) Early extraction of teeth that really cannot be retained. (5) Treat the underlying disease and quit smoking. Prevention (1) The key is to control and eliminate plaque. The most effective method at present is to insist on correct brushing every day, massage the gums, promote blood circulation of the gums, and enhance the resistance of the gum tissue to disease. Pay attention to physical exercise to enhance the immunity of the body. (2) Remove local stimuli, clean teeth and scrape away periodontal tartar and tartar, correct bad restorations and orthodontic food inlays (3) Supplement foods rich in vitamin C, which can regulate the nutrition of periodontal tissues and facilitate the recovery of periodontitis. (4) Periodontal disease should be actively treated after the onset of the disease, the initial effect is still good, the late effect is poor, can lose teeth.