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，从而制定治疗和/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，以确定他们的牙龈下菌斑的成分以及菌斑样本中不同物种之间的联系。这些数据将被用来寻找健康受试者之间的细菌图谱差异，并检查牙周健康受试者和患有牙周炎并正在进行牙周维护的受试者之间的差异。在这项横断面研究中，100名牙周健康的受试者将在每颗牙齿的6个牙周部位进行临床评估。将分别从每颗牙齿的近中面采集牙菌斑样本，并使用棋盘DNA-DNA杂交法对40种细菌的含量进行单独评估。物种在宿主之间的传播对它们在口腔内的生存非常重要。具体目标2将确定指标对象的家庭成员是否被低水平和高红情结定居的指标对象的家庭成员定植。将选择30名高红色复杂指数受试者和30名低红色复杂指数受试者，并对他们的配偶、兄弟姐妹、父母或子女进行临床检查和牙周下菌斑成分检查(如SA1所述)。数据将被用来确定红色复杂物种的低水平或高水平的定居是科内的一个特征。特指目标3将确定家庭中的福赛瑟斯杆菌、牙龈假单胞菌和齿状芽孢杆菌菌株是否显示所选基因的相同DNA碱基序列，这表明该基因在家族内传播。该方法将包括直接从斑块样本中选择的基因进行PCR扩增，然后对产物进行测序。拟议的研究将澄清牙周健康受试者的牙龈下菌斑的组成，确定是否存在一个或多个健康图谱，将健康图谱与疾病受试者在治疗前后的图谱进行比较，为检查菌斑中重要的细菌联系提供数据库，确定假定致病红色复合体的高水平或低水平的定植是在家庭中表现出来的特征，并确定在家庭中发生传播的频率。

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.