Costalonga Massimo, Herzberg Mark C
Division of Periodontology, Department of Developmental and Surgical Sciences, School of Dentistry, University of Minnesota, Minneapolis, MN 55455, United States.
Department of Diagnostic and Biological Sciences, School of Dentistry, University of Minnesota, Minneapolis, MN 55455, United States; Mucosal and Vaccine Research Center, Minneapolis VA Medical Center, Minneapolis, MN 55417, United States.
Immunol Lett. 2014 Dec;162(2 Pt A):22-38. doi: 10.1016/j.imlet.2014.08.017. Epub 2014 Nov 8.
The composition of the oral microbiome differs from one intraoral site to another, reflecting in part the host response and immune capacity at each site. By focusing on two major oral infections, periodontal disease and caries, new principles of disease emerge. Periodontal disease affects the soft tissues and bone that support the teeth. Caries is a unique infection of the dental hard tissues. The initiation of both diseases is marked by an increase in the complexity of the microbiome. In periodontitis, pathobionts and keystone pathogens such as Porphyromonas gingivalis appear in greater proportion than in health. As a keystone pathogen, P. gingivalis impairs host immune responses and appears necessary but not sufficient to cause periodontitis. Historically, dental caries had been causally linked to Streptococcus mutans. Contemporary microbiome studies now indicate that singular pathogens are not obvious in either caries or periodontitis. Both diseases appear to result from a perturbation among relatively minor constituents in local microbial communities resulting in dysbiosis. Emergent consortia of the minor members of the respective microbiomes act synergistically to stress the ability of the host to respond and protect. In periodontal disease, host protection first occurs at the level of innate gingival epithelial immunity. Secretory IgA antibody and other salivary antimicrobial systems also act against periodontopathic and cariogenic consortia. When the gingival immune response is impaired, periodontal tissue pathology results when matrix metalloproteinases are released from neutrophils and T cells mediate alveolar bone loss. In caries, several species are acidogenic and aciduric and appear to work synergistically to promote demineralization of the enamel and dentin. Whereas technically possible, particularly for caries, vaccines are unlikely to be commercialized in the near future because of the low morbidity of caries and periodontitis.
口腔微生物群的组成因口腔内不同部位而异，这在一定程度上反映了每个部位的宿主反应和免疫能力。通过关注两种主要的口腔感染——牙周病和龋齿，出现了新的疾病原理。牙周病会影响支撑牙齿的软组织和骨骼。龋齿是牙体硬组织的一种独特感染。这两种疾病的起始都以微生物群复杂性的增加为特征。在牙周炎中，诸如牙龈卟啉单胞菌等致病共生菌和关键病原体的比例比健康状态下更高。作为关键病原体，牙龈卟啉单胞菌会损害宿主免疫反应，并且似乎是导致牙周炎的必要但不充分条件。从历史上看，龋齿一直被认为与变形链球菌有因果关系。当代微生物群研究表明，无论是龋齿还是牙周炎，单一病原体都不明显。这两种疾病似乎都是由局部微生物群落中相对次要成分之间的扰动导致生态失调引起的。各自微生物群中次要成员形成的新兴菌群协同作用，对宿主的反应和保护能力造成压力。在牙周病中，宿主保护首先发生在固有牙龈上皮免疫水平。分泌型IgA抗体和其他唾液抗菌系统也对牙周病和致龋菌群起作用。当牙龈免疫反应受损时，当中性粒细胞释放基质金属蛋白酶且T细胞介导牙槽骨吸收时，就会导致牙周组织病变。在龋齿中，有几种细菌产酸且耐酸，它们似乎协同作用促进牙釉质和牙本质的脱矿。虽然从技术上来说是可行的，特别是对于龋齿，但由于龋齿和牙周炎的发病率较低，疫苗在不久的将来不太可能实现商业化。
