牙龈卟啉单胞菌PG0717基因与慢性牙周炎的相关性研究

目的检测慢性牙周炎患者和牙周健康者龈下菌斑中牙龈卟啉单胞菌（P.gingivalis）PG0717基因,探讨PG0717基因与牙周临床指数之间的关系。方法选取慢性牙周炎（CP）患者90例和牙周健康者90例,共采集龈下菌斑标本540个;记录临床牙周指数（牙周探诊深度、临床附着丧失和探诊出血）;设计特异性引物检测P.gingivalis阳性龈下菌斑标本的PG0717基因。结果在P.gingivalis阳性龈下菌斑中,CP组PG0717基因检出率显著高于对照组,分别为56.22%和41.27%（掊2=4.50,P＜0.05）;随着牙周探诊深度、临床附着丧失加重和探诊出血趋势的增加,CP组该基因检出率呈现增高趋势。结论PG0717基因与P.gingivalis的致病性有关。     

成人牙周健康状况与fimA基因型牙龈卟啉单胞菌的相关性

目的分析不同fimA基因型牙龈卟啉单胞菌（P.gingivalis）在牙周健康人群和慢性牙周炎人群中的分布,探讨不同fimA基因型P.gingivalis与成人牙周状况的相关关系。方法收集牙周健康组（136例）和慢性牙周炎组（115例）的龈下菌斑样本,采用16S rRNA PCR法检测P.gingivalis,并根据各fimA基因型（Ⅰ～Ⅴ和Ⅰb）的特异性引物检测不同fimA基因型P.gingivalis菌株的分布,计算OR值和95%可信区间。结果牙周健康组和慢性牙周炎组龈下菌斑样本中P.gingivalis阳性率分别为22.1%和81.7%,多数样本中只检测到1种fimA基因型。牙周健康组中ⅠfimA型的检出率最高（占66.7%）;慢性牙周炎组中则为ⅡfimA基因型（占43.6%）,其次为Ⅳ和Ⅰb fimA基因型。慢性牙周炎的发生与P.gingivalis的关系密切（OR=16.36）,Ⅰ、Ⅰb、Ⅱ、Ⅲ、Ⅳ、ⅤfimA基因型P.gingivalis与慢性牙周炎相关性的OR值分别为0.97、13.26、36.62、4.57、22.86、1.19;ⅡfimA基因型P.gingivalis与慢性牙周炎的相关性最强,其次为Ⅳ和Ⅰb型。结论P.gingivalis菌株的fimA基因型存在差异,特异性fimA基因型P.gingivalis可能与成人慢性牙周炎的发生关系密切。     

龈下菌斑中牙龈卟啉单胞菌rgpB基因多态性研究

目的 探讨不同rgpB基因型牙龈卟啉单胞菌在慢性牙周炎发生发展中所起的作用。方法 选择不同牙周状态下的龈下菌斑样本104个，设计引物对牙龈卟啉单胞菌rgpB催化域基因进行扩增，用限制性片段长度多态性分析的方法将牙龈卟啉单胞菌分为4个基因型。结果 慢性牙周炎患者病变重部位rgpB-cdⅣ型检出率最高为52．78％，与Ⅰ、Ⅲ型比较差异有统计学意义（P〈0．05、P〈0．01），病变轻部位rgpB-cdⅡ型检出率为75．86％，显著高于其他型（P〈0．01）。结论rgpB-cdⅣ型可能与慢性牙周炎的关系最密切，在致病过程中起主要作用，而rgpB-cdⅡ型可能与慢性牙周炎无关，为健康人群或牙周健康部位的定居菌。     

不同牙周状态下龈下菌斑中牙龈卟啉单胞菌kgp基因差异研究

目的：探讨不同kgp基因型P.gingivalis在慢性牙周炎发生发展中的作用。方法：选择不同牙周状态下的龈下菌斑样本104个,根据kgp—cd基因序列的不同用限制性片断长度多态性分析的方法将P．gingivalis分为4个基因型。结果：慢性牙周炎患者病变重部位和病变轻部位检出率最高的分别为kgpcdⅡ型（56．25％）和Ⅰ型（51．72％）,对照组仅检出kgp--cdJ型（25％）和Ⅲ型（75％）。结论：kgpcdⅡ型P．gingivalis可能与慢性牙周炎的关系最密切,在致病过程中起主要作用,而kgp—cdⅠ型可能与慢性牙周炎无关,为健康人群或牙周健康部位的定置菌。     

维吾尔族慢性牙周炎中牙龈卟啉单胞菌菌毛fimA毒力基因型的分布

目的:分析维吾尔族慢性牙周炎患者龈下菌斑中牙龈卟啉单胞菌菌毛fimA毒力基因型的分布情况.方法:收集52例维吾尔族慢性牙周炎患者的龈下菌斑,采用16S rRNA PCR法检测牙龈卟啉单胞菌,并根据菌毛fimA毒力基因型的特异引物,用聚合酶链反应(PCR)检测Ⅱ型fimA和Ⅳ型fimA菌株的分布.结果:16S rRNA PCR法检测牙龈卟啉单胞菌在龈下菌斑中阳性检出率是76.9%.牙周袋PPD＞6 mm位点龈下菌斑标本的P.gingivalis检出率高于4＜PPD≤6 mm采样的位点,2组差异有统计学意义(P＜0.05).牙龈卟啉单胞菌菌毛fimA毒力基因型在牙龈卟啉单胞菌感染者的检出率分别是:ⅡfimA型为37.5%,ⅣfimA型为22.5%.结论:维吾尔族慢性牙周炎患者龈下菌斑中牙龈卟啉单胞菌有较高的检出率.牙龈卟啉单胞菌存在fimA毒力基因多态性.     

牙龈卟啉单胞菌毒力岛基因检出与慢性牙周炎的相关性研究

目的:检测慢性牙周炎患者龈下菌斑中牙龈卟啉单胞菌(Porphyromonas gingivalis)毒力岛中PG0836、PG0838和PG0839基因,探讨3个基因与临床牙周指数之间的关系.方法:选取慢性牙周炎(chronic periodoiltitis,CP)患者90例,共采集龈下菌斑标本270个.记录受试位点的牙周探诊深度、临床附着丧失和探诊出血情况.设计特异性引物,检测P.gingivalis阳性龈下菌斑标本的PG0836、PG0838和PG0839基因.采用SPSS 11.0软件包进行统计学分析,采用X2检验对不同牙周临床指数基因的检出率进行比较.结果:在CP患者P.gingivalis阳性龈下菌斑中,PG0836、PG0838和PG0839基因检出率分别为66.17%、24.88%和27.86%.探诊出血阳性位点的PG0839基因检出率(28.35%)显著高于探诊出血阴性位N(14.29%,P<0.05).在牙周探诊深度为4～6mm和>6mm的受试位点,PG0839基因检出率均显著高于牙周探诊深度<4mm的位点(P<0.05).PG0836和PG0838基因在不同牙周指数组检出率无显著差异.结论:PG0839基因的检出与CP病损部位的临床指标呈正相关关系,提示该基因可能与P.gingivalis的致病性有关.     

不同fimA基因型牙龈卟啉单胞菌在慢性牙周炎患者中的分布

目的　分析不同fimA基因型牙龈卟啉单胞菌(P.gingivalis)在慢性牙周炎患者中的分布状况。方法　收集101例慢性牙周炎患者的龈下菌斑,采用常规培养法和16S rRNA PCR检测P.gingivalis,并根据各fimA基因型的特异引物,用聚合酶链反应(PCR)检测不同fimA基因型菌株的分布。结果　16S rRNA PCR检测P.gingivalis阳性检出率为88·1%。大多数受检牙龈下菌斑中只检测出一种fimA基因型菌株(65·1%),各fimA基因型的总检出率: ⅠfimA为24·7%;ⅡfimA为43·8%;ⅢfimA为15·7%;ⅣfimA为40·4%;VfimA为3·4%。结论　慢性牙周炎患者龈下菌斑中的牙龈卟啉单胞菌存在fimA基因多态性,ⅡfimA和ⅣfimA基因型P.gingivalis菌株与慢性牙周炎的发生发展关系密切。     

青春期龈炎龈下菌斑中牙龈卟啉单胞菌kgp基因型的研究

目的 研究青春期龈炎龈下菌斑中牙龈卟啉单胞菌（P.gingivalis）的特异kgp基因型，评估其与疾病严重程度之间的关系。方法检查并记录青春期龈炎组与牙龈健康组各36例的牙周临床指数，收集龈下菌斑样本，提取染色体DNA，采用聚合酶链反应（PCR）方法扩增编码牙龈蛋白酶K（KGP）催化域的序列片段。PCR产物用限制性内切酶Mse I消化。结果 P.gingivalis有毒株W83表现为kgp-A型，而无毒株ATCC33277表现为kgp-B型。所有P.gingivalis阳性个体的龈下菌斑中只检测到一种kgp基因型。kgp-A型在青春期龈炎组P．gingivalis阳性个体中的检出率为79．0％，在牙龈健康组为22．2％，两组kgp基因型的检出率差异有统计学意义（P=0．028）；青春期龈炎组有P.gingivalis定植的个体中，牙周临床指数与kgp的基因型无相关关系（P〉0．05）。结论青春期龈炎个体定植的Pgingivalis的kgp基因型多与有毒株P.gingivalis W83的表现相同，有必要监测kgp-A型阳性的个体，因其个体发展为牙周疾病的危险度可能会增高。     

维吾尔族慢性牙周炎中牙龈卟啉单胞菌菌fimA毒力基因型的分布

目的：分析维吾尔族慢性牙周炎患者龈下菌斑中牙龈卟啉单胞菌菌毛fimA毒力基因型的分布情况。方法：收集52例维吾尔族慢性牙周炎患者的龈下菌斑，采用16SrRNA PCR法检测牙龈卟啉单胞菌，并根据菌毛fima毒力基因型的特异引物，用聚合酶链反应（PCR）检测Ⅱ型fimA和Ⅳ型fima菌株的分布。结果：16SrRNA PCR法检测牙龈卟啉单胞菌在龈下菌斑中阳性检出率是76．9％。牙周袋PPD〉6mm位点龈下菌斑标本的P．gingivalis检出率高于4〈PPD≤6mm采样的位点，2组差异有统计学意义（P〈0．05）。牙龈卟啉单胞菌菌毛．fimA毒力基因型在牙龈卟啉单胞菌感染者的检出率分别是：Ⅱ fimA型为37．5％，ⅣfimA型为22．5％。结论：维吾尔族慢性牙周炎患者龈下菌斑中牙龈卟啉单胞菌有较高的检出率。牙龈卟啉单胞菌存在fima毒力基因多态性。     

反向基因芯片技术检测牙龈卟啉单胞菌致病岛基因

目的：应用反向基因芯片技术检测PG0836、PG0838、PG0839基因在慢性牙周炎患者和牙周健康者牙龈卟啉单胞菌（P.gingivalis）中分布,探讨这些基因与牙周临床指数之间的关系。方法：选取41例慢性牙周炎患者,牙周健康者76例,记录临床指标牙周探诊深度、临床附着丧失、探诊出血及牙齿松动度,取龈下菌斑进行细菌分离培养,以临床采集的样本提取的DNA为探针,以抑制消减杂交技术获得的P.gingivalis W83的特异基因片段PG0836、PG0838、PG0839为目标序列,采用Cy5荧光标记目标序列。应用基因芯片技术检测PG0836、PG0838、PG0839基因在病变部位及非病变部位的牙龈卟啉单胞菌中的分布。结果：PG0836、PG0838、PG0839基因在病变部位和非病变部位中的检出率均有统计学差异（P〈0.05）,并且与牙周临床指数PD、CAL、TM相关。结论：PG0836、PG0838、PG0839基因与P.gingivalis的致病性有关。     

青春期龈炎龈下菌斑中牙龈卟啉单胞菌的检测

目的:检测青春期龈炎患者龈下菌斑中牙龈卟啉单胞菌(Porphyromonas gingivalis,Pg)的存在情况,探讨青春期Pg与牙龈健康状况的关系。方法:14～17岁青春期龈炎患者及牙龈健康者各36例,采用16SrRNA聚合酶链反应(polymerase chain reaction,PCR)检测2组受检者的龈下菌斑样本中Pg的存在,并用电泳凝胶成像分析软件检测各电泳条带的平均灰度值,计算Pg的相对含量;同时检测并记录受检者的各牙周指数测值,观察其与Pg相对含量的相关性。数据用SPSS11.5软件包作统计学分析。2组Pg阳性检出率的比较采用χ2检验;Pg的相对含量以及Pg阳性检出者与阴性检出者的牙龈炎严重度的比较采用Wilcoxon秩和检验;Pg的相对含量与各牙周指数之间的相关关系采用Spearman相关分析。结果:青春期龈炎组与牙龈健康组的龈下菌斑中Pg的阳性检出率分别为47.22%和25.00%,两者之间具有显著性差异(P<0.05);青春期龈炎组与牙龈健康组的Pg在龈下菌斑中的平均相对含量分别为48.02%和21.46%,统计学上有高度显著性差异(P<0.01);在青春期龈炎组Pg阳性个体中,Pg的相对含量与牙龈指数(gingivalindex,GI)、龈沟出血指数(sulcusbleedingindex,SBI)、探诊深度(probedepth,PD)数值的高低呈正相关;青春期龈炎组中,Pg阳性检出者的GI、SBI数值高于阴性检出者,两者之间具有高度显著性差异(P<0.01)。结论:青春期个体的龈下菌斑中有Pg的定植,且与牙龈健康状况有密切关系。     

不同fimA基因型牙龈卟啉单胞菌在牙周健康人群中的分布

目的调查不同fimA基因型牙龈卟啉单胞菌 (P.gingivalis)在牙周健康人群中的分布情况。方法收集136例牙周健康者的龈下菌斑样本,采用16S rRNAPCR法检测P.gingivalis;并根据各fimA基因型特异性引物,用PCR法检测不同fimA基因型P.gingivalis的分布。 结果136例牙周健康者的龈下菌斑样本中携带P.gingivalis的阳性率为22.1%。大多数受检者龈下菌斑中只检测到1种fimA基因型 P.gingivalis菌株(80.0%);5例样本检出了2种fimA型P.gingivalis(16.7%),且均为ⅠfimA型与其它fimA 型P.gingivalis的联合检出。各fimA型P.gingivalis的检出情况:Ⅰ型(66.7%)、Ⅰb型(6.7%)、Ⅱ型(6.7%)、 Ⅲ型(10%)、Ⅳ型(6.7%)、Ⅴ型(16.7%)。Ⅰ型的检出率明显高于其它各型,差异有统计学意义(P<0.05);其它各fimA型 P.gingi-valis间的检出差异均无统计学意义。结论本研究条件下ⅠfimA型P.gingivalis在牙周健康人群中检出例数最高,提示:我 国牙周状况不同人群携带的P.gingivalis菌株fimA基因型可能存在差异。?     

成人正畸患者龈下菌斑中牙龈卟啉单胞菌的变化

目的研究成人正畸患者在固定矫治器戴入后,其牙周临床指标和龈下菌斑中牙龈卟啉单胞菌（P.gingivalis）的早期变化。方法选择成人正畸患者11例,分别在矫治器戴入前,戴入后第1、3个月检查牙周临床指标（包括菌斑指数、龈沟出血指数、探诊深度和附着丧失）,同时采集龈下菌斑样本,利用荧光实时定量聚合酶链反应检测样本中P.gingivalis和总细菌的数量,计算出P.gingivalis的检出率和构成比。分析牙周临床指标和P.gingivalis的检出率、构成比在不同观察时点的变化情况。结果菌斑指数、龈沟出血指数在矫治器戴入后均比戴入前明显升高（P<0.05）。探诊深度在矫治器戴入1个月后升高（P<0.05）,3个月后下降至基线水平。试验中未发现有探诊深度大于2 mm的患者,也未发现有附着丧失的患者。在3次检测中,P.gingivalis检出率均为45.5%,而P.gingivalis构成比的变化也无统计学差异（P>0.05）。结论固定矫治器戴入早期可引发成人正畸患者口内局部菌斑堆积,菌群中P.gingivalis增殖,出现轻度牙龈炎。     

慢性牙周炎患者龈下菌斑中不同基因型牙龈卟啉单胞菌的检测

摘要 目的:建立临床标本中牙龈卟啉单胞菌(P.g)的PCR检测方法,探讨慢性牙周炎患者不同牙位的龈下菌斑中P.g基因型的差异。方法:采用培养法分离鉴定慢性牙周炎患者不同牙位龈下菌斑中P.g,同时采用PCR检测 P.g16SrDNA、prtC和fimA基因。部分扩增产物测定了核苷酸序列。结果:在66例患者的127个龈下菌斑标本中, P.g16SrDNA、prtC和fimA多重引物扩增的阳性率为9814%;PCR阳性率显著高于培养法P.g的检出率(P< 0101)。3010%的患者(18/60)同时感染了不同基因型的P.g菌株。P.g16SrDNA、prtC和fimA扩增片段的核苷酸序列同源性在98162%~100%之间。结论:本文所建立的P.g的PCR检测方法具有较高的敏感性和特异性,适用于P.g的快速临床诊断。同一患者可被不同感染来源的多株P.g同时感染。     

牙周基础治疗对慢性牙周炎患者临床指标及5种牙周可疑致病微生物的影响

目的:观察牙周基础治疗对临床指标及5种牙周可疑致病微生物的影响。方法:选取20例慢性牙周炎患者(40个位点),在治疗前和基础治疗后3个月时检测观测位点的临床指标牙周探诊深度(PPD),临床附着丧失(CAL)和探诊出血(BOP),同时采集龈下微生物样本。采用PCR和反杂交的方法对所采集微生物样本中的牙龈卟啉单胞菌、福赛斯坦纳菌,中间普氏菌、伴放线放线杆菌和齿垢密螺旋体进行半定量检测。结果:通过牙周基础治疗后临床指标PPD及BOP的改善具有统计学意义(P<0.001),而CAL的改善不具有统计学意义。治疗后牙龈卟啉单胞菌、福赛斯坦纳菌和齿垢密螺旋体的检出量显著减少(P<0.05或P<0.001)。治疗前PPD>6mm的位点只有福赛斯坦纳菌在治疗后比治疗前有显著减少(P<0.05),而牙龈卟啉单胞菌和齿垢密螺旋体的变化不具有统计学意义。结论:基础治疗是治疗慢性牙周炎的有效方法,可改善临床指标,减少龈下牙龈卟啉单胞菌、福赛斯坦纳菌和齿垢密螺旋体的数量。但在PPD>6mm的位点基础治疗对于这五微生物的影响作用是有限的。     

Description of the subgingival microbiota of periodontally untreated Mexican subjects: chronic periodontitis and periodontal health

BACKGROUND: Recent studies have suggested that changes in the prevalence and/or proportion of distinct microorganisms characterize the subgingival microbial profiles of populations around the world. At present, no information is available on the subgingival microbiota of Mexican subjects. The purpose of the present study was to determine the microbial composition of subgingival plaque in Mexican subjects with untreated chronic periodontitis. METHODS: A total of 44 chronic periodontitis and 20 periodontally healthy subjects (who were currently non-smokers) were selected. Clinical measurements including plaque accumulation, gingival erythema, bleeding on probing, suppuration, probing depth, and attachment level were recorded at six sites of every tooth. Up to 28 subgingival plaque samples were obtained from each subject and individually analyzed to determine the levels, proportion, and prevalence of 40 microbial species using the checkerboard DNA-DNA hybridization technique. RESULTS: Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythensis were the only species that presented higher mean levels in periodontitis subjects. The proportions of P. gingivalis (P<0.001), T. forsythensis (P<0.01), and red complex species (P. gingivalis, T. forsythensis, and T. denticola; P<0.001) as a group were also significantly higher in periodontitis subjects. Periodontally healthy subjects harbored a significantly larger proportion of Actinomyces species (P<0.05). No significant differences were detected in the percentage of carriers of any of the species tested. CONCLUSIONS: Our results revealed that the subgingival microbiota of untreated chronic periodontitis Mexican subjects was characterized by increases in the level, prevalence, and proportion of classic periodontal pathogens. However, the prevalence and proportion of specific microbial species varied significantly from the results of other reports on subjects from different geographical locations.     

Sequence variations in rgpA and rgpB of Porphyromonas gingivalis in periodontitis

Objective:  The aim of the present study was to determine sequence variations in the active centre of the Arg-X-specific protease encoding genes rgpA and rgpB of clinical Porphyromonas gingivalis isolates and to analyse their prevalence in periodontitis patients before and 3 months after mechanical periodontal therapy.
Background:  Genetic diversity at nucleotides 281, 283, 286 and 331 has been shown to result in amino acid substitutions in the catalytic domain of RgpA and RgpB that affect the substrate specificity and thus may influence the efficacy of Arg-X-protease specific inhibitors.
Methods:  Sequence analysis of rgpA and rgpB genes in clinical P. gingivalis strains isolated from subgingival plaque samples of 82 periodontitis patients before and 3 months after mechanical supra- and subgingival debridement was performed.
Results:  No specific variation within the rgpA sequence was observed. However, the rgpB sequence in the region of the active centre showed five different rgpB genotypes, which were named NYPN, NSSN, NSSK, NYPK and DYPN according to the derived amino acid substitution. Porphyromonas gingivalis genotype NYPN was detected in 27 patients (32.9%) before and in 8 patients (9.8%) after therapy, NSSN in 26 (31.7%) and 10 (12.2%), NSSK in 22 (26.8%) and 2 (2.4%), NYPK in 5 (6.2%) and 1 (1.2%), and DYPN in 1 patient (1.2%) and 0 patients (0%), respectively. Only one patient (1.2%) harboured two P. gingivalis rgpB genotypes (NSSK/NYPN) before treatment; these were no longer detected after therapy.
Conclusion:  The results indicate that five rgpB genotypes are maintained in natural populations of P. gingivalis. These data may be of importance with regard to the development of specific rgpB inhibitors.     

Detection frequency of periodontitis-associated bacteria by polymerase chain reaction in subgingival and supragingival plaque of periodontitis and healthy subjects

The aim of this study was to compare the detection frequencies of 25 bacterial species in subgingival and supragingival plaque of 18 untreated periodontitis subjects and 12 periodontally healthy subjects. Genomic DNA was extracted from subgingival and supragingival plaque samples, and bacterial detection was performed by polymerase chain reaction of the 16S rRNA genes. Fourteen bacteria showed no relationship with periodontitis, and 11 of these 14 species were frequently detected (≥50%) in subgingival plaque in both periodontitis and healthy subjects. Nine bacteria such as Eubacterium saphenum, Prevotella intermedia, and Treponema denticola seemed to be related to periodontitis; their detection frequencies in subgingival plaque samples were higher in periodontitis than in healthy subjects, but these differences were not statistically significant by multiple comparisons (0.002≤ P< 0.05). Two species ( Mogibacterium timidum and Porphyromonas gingivalis ) were detected significantly more frequently in subgingival plaque of periodontitis subjects than of healthy subjects ( P< 0.002), with P. gingivalis being detected only in periodontitis subjects, suggesting that these two species are closely related to periodontitis. There were no significant differences in the detection frequencies of the 25 bacteria between subgingival and supragingival plaque, suggesting that the bacterial flora of supragingival plaque reflects that of subgingival plaque.     

Site-specific development of periodontal disease is associated with increased levels of Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia in subgingival plaque

BACKGROUND: Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia (previously T. forsythensis), which are regarded as the principal periodontopathogenic bacteria, exist as a consortium in subgingival biofilms. We aimed to examine quantitative relationships between P. gingivalis, T. denticola, and T. forsythia in subgingival biofilms and the relationship between the quantity and prevalence of these three bacteria and site-specific periodontal health. METHODS: This study was cross-sectional. The study population consisted of 35 adult subjects who visited the Kyushu Dental College Hospital. Plaque samples were collected from 105 periodontal pocket sites. Quantitative analyses of each of the three periodontopathogenic bacteria were performed using real-time polymerase chain reaction with species-specific primers and hybridization probes. RESULTS: The plaque samples were divided into four groups based on the presence or absence of a periodontal pocket (probing depth [PD] > or =4 mm) and bleeding on probing (BOP), regardless of attachment loss. The proportions of all three target bacteria detected in samples from sites of periodontal disease (with PD and BOP) were markedly higher than those in the other sample groups. Cell numbers of P. gingivalis, T. denticola, and T. forsythia in the subgingival plaque of each sampling site were significantly mutually correlated and were increased in the plaque of sites of periodontal disease with PD > or =4 mm and BOP. CONCLUSION: The symbiotic effects of P. gingivalis, T. denticola, and T. forsythia, which coaggregate and exist concomitantly in subgingival biofilms, may be associated with the local development of periodontitis.     

Progression of chronic periodontitis can be predicted by the levels of Porphyromonas gingivalis and Treponema denticola in subgingival plaque

Introduction:  Chronic periodontitis is an inflammatory disease of the supporting tissues of the teeth associated with bacteria. Diagnosis is achieved retrospectively by clinical observation of attachment loss. Predicting disease progression would allow for targeted preventive therapy. The aim of this study was to monitor disease progression in patients on a maintenance program and determine the levels of specific bacteria in subgingival plaque samples and then examine the ability of the clinical parameters of disease and levels of specific bacteria in the plaque samples to predict disease progression.
Methods:  During a 12-month longitudinal study of 41 subjects, 25 sites in 21 subjects experienced disease progression indicated by at least 2 mm of clinical attachment loss. Real-time polymerase chain reaction was used to determine the levels of Porphyromonas gingivalis , Treponema denticola , Tannerella forsythia , Fusobacterium nucleatum , and Prevotella intermedia in subgingival plaque samples.
Results:  No clinical parameters were able to predict periodontal disease progression. In sites undergoing imminent periodontal disease progression within the next 3 months, significant partial correlations were found between P. gingivalis and T. forsythia ( r  = 0.55, P  < 0.001) and T. denticola and T. forsythia ( r  = 0.43, P  = 0.04). The odds of a site undergoing imminent periodontal disease progression increased with increasing levels of P. gingivalis and T. denticola .
Conclusion:  Monitoring the proportions of P. gingivalis and T. denticola in subgingival plaque has the potential to help identify sites at significant risk for progression of periodontitis, which would assist in the targeted treatment of disease.