MICROBIAL ECOLOGY OF PERIODONTAL DISEASES

该项目的长期目标是确定与牙周健康最相容的微生物复合体，从而产生治疗和/或预防策略，以产生所需的菌斑成分。具体目标1将检查牙周健康受试者，以确定其龈下菌斑的成分和菌斑样本中物种之间的关联。这些数据将用于寻找健康受试者之间的细菌谱差异，并检查牙周健康受试者与牙周炎受试者和牙周维护受试者之间的差异。在这项横断面研究中，100名牙周健康受试者将在每颗牙齿的6个牙周部位进行临床评估。龈下菌斑样本将分别从每颗牙齿的近中面采集，并使用棋盘DNA-DNA杂交法单独评估40种细菌的含量。物种在宿主之间的传播对于它们的口内生存很重要。具体目标2将确定索引受试者的家庭成员是否比高红复合物定殖索引受试者的家庭成员被低水平和患病率定殖。 将选择30名高红色复合指数和30名低红色复合指数受试者，并对其配偶、兄弟姐妹、父母或子女进行临床检查和龈下菌斑组成检查（如SA 1所述）。数据将被用来确定是否殖民低或高水平的红色复杂的物种是一个家庭内的特点。特异性目标3将确定是否存在B菌株。P. gingivalis和T.家族中的齿垢显示出选定基因的相同DNA碱基序列，表明家族内传播。该方法将涉及直接从噬菌斑样品中PCR扩增所选基因，然后对产物进行测序。拟议的研究将阐明牙周健康受试者龈下菌斑的组成，确定是否存在一个或多个健康概况，将健康概况与治疗前后疾病受试者的概况进行比较，为检查菌斑中重要的细菌关联提供数据基础，确定高水平或低水平的假定致病性红色复合物的定殖是否是家族内表现出的特征，并确定传播发生在家庭内部。

The long-term objectives of this Project are to define the microbial complexes that are most compatible with periodontal health leading to therapeutic and/or preventive strategies to produce the desired plaque composition Specific Aim 1 will examine periodontally health subjects in order to determine the composition of their subgingival plaque and the associations among species within the plaque samples. The data will be used to seek differences in bacterial profiles among health subjects and examine differences between periodontally healthy subjects and subjects who have periodontitis and who are on periodontal maintenance. In this cross- sectional study, 100 periodontally healthy subjects will be assessed clinically at 6 periodontal sites per tooth. Subgingival plaque samples will be take separately from the mesial aspect of each tooth and evaluated individually for their content on 40 bacterial species using checkerboard DNA-DNA hybridization. The dissemination of species from host to host is important for their intraoral survival. Specific Aim 2 will determine if family members of index subjects colonized by low levels and prevalence than family members of high-red-complex colonized index subjects. 30 high and 30 low red complex index subjects will be chosen and their spouses, siblings, parents or children examined clinically and for subgingival plaque composition (as described for SA1). Data will be used to determine if colonization by low or high levels of red complex species is a trait within families. Specific Aim 3 will determine if strains of B. forsythus, P. gingivalis and T. denticola in families show identical DNA base sequences for selected genes, suggesting transmission within the family. The method will involve PCR amplification of the chosen gene directly from plaque samples, followed by sequencing of the product. The proposed studies will clarify the composition of subgingival plaque in periodontally healthy subjects, determine if one or more healthy profiles exist, compare healthy profiles to profiles of diseases subjects before and after therapy, provide a data base for examining important bacterial associations in plaque, determine if colonization by high or low levels of the presumed pathogenic red complex is a trait exhibited within families and determine how frequently transmission occurs within families.