Asikainen S, Chen C
Institute of Dentistry, University of Helsinki, Finland.
Periodontol 2000. 1999 Jun;20:65-81. doi: 10.1111/j.1600-0757.1999.tb00158.x.
The ecological characteristics of the oral cavity are dissimilar for A. actinomycetemcomitans and for P. gingivalis, as judged by differences in their colonization preferences and patterns, associations with periodontal disease parameters, relationships with the subgingival microbiota and the type of periodontitis and their clonal persistence in the oral cavity. These features also suggest that as a periodontal pathogen, A. actinomycetemcomitans is different from P. gingivalis. Probably in most infected individuals, low levels of A. actinomycetemcomitans can persist for years in equilibrium with the host and the resident oral microbiota. However, it is well established that A. actinomycetemcomitans can cause disease in some individuals or in some circumstances when the regulatory mechanisms are unable to maintain homeostasis in the ecosystem. Elevated A. actinomycetemcomitans proportions of the biota can be regarded as a sign of ecological imbalance, leading to increased risk of periodontal destruction. There is also evidence showing elevated pathogenic potential of certain A. actinomycetemcomitans clones. Although A. actinomycetemcomitans seems to be relatively rarely transmitted between cohabiting adults, transmission can occur to periodontally healthy children of A. actinomycetemcomitans-positive parents. Parents and children may share factors that promote successful oral colonization of A. actinomycetemcomitans, or the window of opportunity is in childhood. Therefore, to prevent parent-child transmission of A. actinomycetemcomitans, bacterium-positive parents of young children are optimal targets for enhanced information and treatment. In selected populations, screening for specific clones of A. actinomycetemcomitans has been employed in prevention of peridontitis. Future research aiming at finding the reasons which cause the changes in the oral homeostasis to allow the growth of A. actinomycetemcomitans may give insight into novel prevention strategies for A. actinomycetemcomitans-associated periodontitis. Compared with A. actinomycetemcomitans, P. gingivalis shows a different pattern of coexistence with the host. In periodontal health or in children, P. gingivalis is absent or only rarely detected. When present, P. gingivalis is commonly recovered in high numbers from dentitions exhibiting inflamed periodontitis and poor oral hygiene. Contrary to A. actinomycetemcomitans, the data on the vertical transmission of P. gingivalis are limited. The major infection route of P. gingivalis seems to be between adults, indicating that P. gingivalis commonly colonizes in an established oral microbiota. These characteristics suggest that the degree of tolerance between P. gingivalis and the host is inferior to that between A. actinomycetemcomitans and the host. It appears that the association of P. gingivalis with disease is a rule rather than an accidental incident. On these grounds, it seems that the host-P. gingivalis relationship approaches antibiosis. Since P. gingivalis infection is related to a typical periodontal eco-pathology, the susceptibility to person-to-person transmission of this pathogen may be controlled by periodontal treatment and emphasizing the significance of high standard oral hygiene.
根据伴放线放线杆菌和牙龈卟啉单胞菌在定植偏好和模式、与牙周病参数的关联、与龈下微生物群的关系、牙周炎类型以及它们在口腔中的克隆持续性等方面的差异判断，口腔的生态特征对这两种菌而言是不同的。这些特征还表明，作为一种牙周病原体，伴放线放线杆菌与牙龈卟啉单胞菌不同。在大多数受感染个体中，伴放线放线杆菌的低水平可能与宿主和口腔常驻微生物群处于平衡状态并持续数年。然而，众所周知，当调节机制无法维持生态系统的稳态时，伴放线放线杆菌在某些个体或某些情况下会引发疾病。生物群中伴放线放线杆菌比例升高可被视为生态失衡的标志，会导致牙周破坏风险增加。也有证据表明某些伴放线放线杆菌克隆的致病潜力增强。虽然伴放线放线杆菌在同居成年人之间的传播似乎相对少见，但伴放线放线杆菌呈阳性的父母可将其传播给牙周健康的儿童。父母和孩子可能共享促进伴放线放线杆菌在口腔成功定植的因素，或者机会窗口在儿童期。因此，为防止伴放线放线杆菌的亲子传播，幼儿细菌呈阳性的父母是加强信息宣传和治疗的最佳目标人群。在特定人群中，已采用筛查伴放线放线杆菌的特定克隆来预防牙周炎。未来旨在找出导致口腔稳态变化从而使伴放线放线杆菌得以生长的原因的研究，可能会为伴放线放线杆菌相关牙周炎的新型预防策略提供思路。与伴放线放线杆菌相比，牙龈卟啉单胞菌与宿主的共存模式不同。在牙周健康状态下或在儿童中，牙龈卟啉单胞菌不存在或仅很少被检测到。当存在时，牙龈卟啉单胞菌通常在患有炎症性牙周炎且口腔卫生差的牙列中大量检出。与伴放线放线杆菌相反，牙龈卟啉单胞菌垂直传播的数据有限。牙龈卟啉单胞菌的主要感染途径似乎是在成年人之间，这表明牙龈卟啉单胞菌通常定植于已有的口腔微生物群中。这些特征表明，牙龈卟啉单胞菌与宿主之间的耐受程度低于伴放线放线杆菌与宿主之间的耐受程度。牙龈卟啉单胞菌与疾病的关联似乎是一种常态而非偶然事件。基于这些理由，宿主与牙龈卟啉单胞菌的关系似乎接近抗生现象。由于牙龈卟啉单胞菌感染与典型的牙周生态病理学相关，这种病原体在人际传播中的易感性可能通过牙周治疗以及强调高标准口腔卫生的重要性来控制。
