The difference between insect tooth and fire tooth is as follows: 1, the definition is different: caries is commonly known as worm tooth, tooth decay, is a bacterial disease, can be followed by pulpitis, periapical inflammation and even can cause inflammation of jaw bone; if not treated in time, the lesion will continue to develop, and eventually the crown will be completely destroyed and disappear, and the final result is tooth loss; periodontitis is known as fire tooth in folklore; in folklore, some people only know fire tooth but do not know periodontitis, periodontitis is an invasion of Periodontitis is a chronic inflammation invading the gum and periodontal tissue, it is a destructive disease, its main characteristic is the formation of periodontal pocket and pocket wall inflammation, alveolar bone resorption and teeth gradually loosening, it is the main cause of adult tooth loss; 2, the pathogenesis is different: caries causes mainly include bacteria, oral environment host and time; cariogenic food sugar clings to the tooth surface, formed by salivary protein to obtain a membrane, this membrane is not only firmly This film is not only firmly attached to the tooth surface, but also can have enough time to produce acid in the deep layer of plaque under the suitable temperature, invade the tooth to demineralize and destroy the organic matter to produce cavities; while periodontitis is caused by plaque, tartar, food embedment, bad restoration, occlusal trauma, etc. causing gingival inflammation and swelling, while the plaque accumulation is aggravated and the supra-gingival to subgingival expansion; due to the characteristics of subgingival microecological environment, the subgingival plaque breeds a large number of virulent Due to the characteristics of the subgingival microecological environment, a large number of virulent periodontal pathogenic bacteria and spirochetes in the subgingival plaque aggravate and expand the gingival inflammation, resulting in the formation of periodontal pockets and alveolar bone resorption, causing periodontitis.