不同程度颈动脉狭窄患者动脉粥样硬化斑块中牙周致病菌的分布研究

目的 检测不同程度颈动脉狭窄患者动脉粥样硬化斑块与龈下菌斑中的牙周致病菌分布。方法 选取需要进行颈动脉内膜剥脱术的患者50例,按照颈动脉狭窄程度分为重度狭窄组(36例)和完全闭塞组(14例)。收集术中分离的颈动脉粥样硬化斑块和龈下菌斑,采用16S rRNA PCR检测伴放线聚集杆菌(Actinobacillus actinomycetemcomitans,A.actinomycetemcomitans)、福赛坦纳菌(Tanerella forsythia,T.forsythia)、齿垢密螺旋体(Treponema denticola,T.denticola)、具核梭杆菌(Fusobacterium nucleatum,F.nucleatum)和牙龈卟啉单胞菌(Porphyromonas gingivalis,P.gingivalis)5种牙周致病菌的分布。结果 P.gingivalis、T.denticola、T.forsythia、F.nucleatum在完全闭塞组颈动脉粥样硬化斑块的检出率分别为71.4%、64.3%、42.9%和14.3%,高于在重度狭窄患者中的检出率,其中两组间...     

Nd: YAP激光治疗牙周炎的疗效评价及其对龈下微生物的影响

目的 比较龈下刮治和根面平整术(scaling and root planning, SRP)联合Nd:YAP激光与单纯SRP治疗对牙周炎患者疗效的差异和龈下微生物的影响。方法 选择符合纳入标准的牙周炎患者。每位患者龈上洁治1周后为本研究基线,随机半口分组。试验侧采用SRP联合Nd: YAP激光治疗;对照侧仅采用SRP治疗。每位患者选择一组同颌同名单根牙,进行龈沟液(gingival crevicular fluid, GCF)和龈下菌斑取样。分别在基线、治疗完成后6周和12周进行探诊深度(probing depth, PD)和探诊出血(bleeding on probing, BOP)的数据采集、龈沟液及龈下菌斑样本的采集。ELISA法检测龈沟液中炎症因子白细胞介素6(interleukin-6,IL-6)的浓度。16S rDNA高通量测序对各龈下菌斑样本的菌群构成进行分析和比较。结果 试验侧与对照侧的各项临床指标较基线时均有显著改善(P＜0.05),但两组间无明显差异。两组的IL-6浓度较基线均显著下降,治疗后6周,试验侧的 IL-6浓度明显低于对照组(P＜0.05)。龈下菌斑α多样性分析,治疗后6周及12周,对照侧的Shannon指数高于基线,Simpson指数低于基线(P＜0.05)。测序结果显示,治疗后6周,试验侧的普氏菌属(Prevotella)和Saccharibacteria_incertae_incerta_sedis的相对丰度较基线显著下降;密螺旋体属(Treponema)的相对丰度低于对照侧,嗜二氧化碳噬细胞菌属(Capnocytophaga)的相对丰度高于对照侧(P＜0.05),12周时无明显差异。结论 在本研究中,Nd:YAP激光联合SRP和单纯SRP治疗牙周炎均有明显效果,而两种治疗方法在临床指标上无明显差异,辅助使用Nd:YAP激光在短时间内更有利于GCF IL-6浓度的降低和部分牙周致病菌的控制。     

牙周致病微生物与药物性牙龈肥大的关系

目的:探讨菌斑微生物在硝苯地平诱导的药物性牙龈肥大中的作用。方法:采用Real-time PCR技术对服用硝苯地平后出现药物性牙龈肥大的高血压患者(A组,23例)、服用硝苯地平后未出现药物性牙龈肥大的高血压患者(B组,23例)、慢性牙周炎者(C组,23例)龈下菌斑内牙龈卟啉单胞菌(Porphyromonas gingivalis,Pg)、中间普氏菌(Prevotella intermedia,Pi)、齿垢密螺旋体(Treponema denticola,Td)和福赛坦氏菌(Tannerella forsythia,Tf)进行相对定量检测,比较3组患者龈下菌斑中4种牙周致病微生物相对含量的差异。结果:Pg、Td、Tf、Pi在A组明显高于B组,两者之间有统计学差异(P<0.05), A组与C组比较无统计学差异。结论:菌斑微生物在硝苯地平诱导的药物性牙龈肥大中起着重要作用。     

慢性牙周炎通过PERK-CHOP信号通路介导睾周脂肪细胞凋亡的研究

目的 探讨慢性牙周炎通过蛋白激酶R样内质网激酶(protein kinase R-like ER kinase,PERK)-C/EBP同源蛋白(C/EBP homologous protein,CHOP)信号通路对大鼠睾周脂肪细胞凋亡的影响。方法 将20只雄性SD大鼠随机分为实验组和对照组。实验组构建大鼠慢性牙周炎模型,对双侧上颌第二磨牙行丝线结扎并龈沟内注射牙龈卟啉单胞菌脂多糖(Porphyromonas gingivalis-lipopolysaccharid,P. gingivalis-LPS);对照组大鼠龈沟内注射等量PBS。建模3个月后处死大鼠,通过测量牙龈出血指数(gingival bleeding index,GBI)及牙周袋探诊深度(probing pocket depth,PPD)评价牙周组织炎症,采用Micro-CT分析大鼠第二磨牙牙槽骨吸收程度。原位细胞凋亡检测法(TUNEL)染色观察睾周脂肪细胞凋亡情况。蛋白质印迹法(Western blot)检测PERK、p-PERK、CHOP、Caspase-12、Cleaved-Caspase-3的蛋白表达水平。结果 实验组大鼠GBI、PPD及釉牙骨质界至牙槽嵴顶距离显著高于对照组(P<0.05),出现明显牙龈软组织炎症和牙槽骨破坏吸收,大鼠慢性牙周炎模型建立成功。实验组大鼠睾周脂肪细胞凋亡率显著增加(P<0.05),p-PERK、CHOP、Caspase-12、Cleaved-Caspase-3蛋白表达水平显著升高(P<0.05)。结论 慢性牙周炎通过PERK-CHOP信号通路介导大鼠睾周脂肪细胞的凋亡。     

不同牙周状态下龈沟液中瘦素水平的比较

目的:检测牙周健康者、慢性龈炎和慢性牙周炎患牙龈沟液中瘦素水平,为牙周炎的早期诊断提供客观指标。方法:选择牙周健康者、慢性龈炎和慢性牙周炎患者3组,治疗前记录牙周各项临床指标,并用Whatman^ 1号滤纸收集颊侧近远中牙周袋内GCF采用ELISA检测瘦素含量;同时收集血清进行瘦素水平的检测。结果:3组中慢性牙周炎组龈沟液中瘦素水平与牙周健康者龈沟液中瘦素水平比较有显著差异(P<0.05),慢性牙周炎组龈沟液中瘦素水平与慢性龈炎龈沟液中瘦素水平及慢性龈炎组龈沟液中瘦素水平与牙周健康者龈沟液中瘦素水平比较均无显著差异;牙周健康者、慢性龈炎和慢性牙周炎患者血液中瘦素水平比较均有显著差异(P<0.05)。血中的瘦素与临床指标PLI (P<0.01,r=0.593)、PD(P<0.05,r=0.920)、BI(P<0.05,r=0.862)、AL(P<0.05,r=0.846)均相关;龈沟液中的瘦素与临床指标PLI(P<0.01,r=0.813)、PD(P<0.05,r=0.962))、BI(P<0.05,r=0.720、AL(P<0.05,r=0.946)均相关。结论:龈沟液中瘦素水平可能是反映牙周组织状况的一项较为客观的指标。     

种植义齿排龈后种植体周围软组织损伤愈后的动物实验研究

目的 通过观察比格犬种植义齿排龈后牙龈指数、龈沟液量和龈沟液中炎症细胞因子肿瘤坏死因子-α（TNF-α）等指标的变化,探讨排龈所致种植义齿周围软组织损伤愈后情况。方法 拔除8只比格犬左侧下颌第四前磨牙（n=8）,严格控制口腔菌斑,2个月后行骨水平种植体植入,3个月后行全冠粘接固位。全冠粘接前使用排龈线排龈5 min,排龈前和排龈后1、3、7、14、28、56 d,分别记录种植体的牙龈指数,测量龈沟液量并用酶联免疫吸附试验检测龈沟液中TNF-α的变化。 结果 种植体牙龈指数、龈沟液量、TNF-α在排龈后第1、3、7天均大于排龈前和排龈后第14、28、56天（P<0.05）,第14、28、56天恢复至排龈前水平,差异无统计学意义（P>0.05）。结论 保持良好口腔卫生的情况下,骨水平种植义齿周围软组织排龈线造成的排龈损伤是可逆性损伤,牙龈指数、龈沟液量、TNF-α在第14天恢复至排龈前水平。     

伴2型糖尿病的慢性牙周炎牙周可疑致病菌的检测

目的 检测伴2型糖尿病(diabetes mellitus,DM)的慢性牙周炎(chronic periodontitis,CP)患者龈下菌斑中牙周可疑致病菌的种类和构成,从微生物学角度探讨牙周炎与DM的相互作用机制.方法 采集伴2型DM的CP患者154例(DM组)、不伴DM的单纯CP患者120例(CP组)及40名全身及牙周健康者(N组)的龈下集合菌斑,传统酚-氯仿法提取菌斑DNA,以牙龈卟啉单胞菌(Porphyromonas gingivalis,Pg),伴放线放线杆菌(Actinobacillus actinomycetemcomitans,Aa),具核梭杆菌(Fusobacterium nucleatum,Fn),中间普氏菌(Prevotella intermedia,Pi),福塞坦氏菌(Tannerella forsythia,Tf),齿垢密螺旋体(Treponema denticola,Td)为目标菌,应用以16SrRNA为基础的聚合酶链反应(PCR)技术对龈下菌群进行检测.结果 Pg、Aa、Fn、Pi、Tf、Td在DM组中均可检出;与CP组相比,在性别、年龄、牙周状况基本一致的情况下,轻度牙周炎者DM组Pi的检出率为35%(8/23),CP组为65%(13/20),两组间差异有统计学意义(P<0.05);重度牙周炎者DM组Pg、Aa、Tf的检出率分别为78%(72/92)、27%(25/92)、67%(62/92),CP组分别为58%(35/60)、17%(10/60)、43%(26/60),DM组均显著高于CP组,差异有统计学意义(P<0.05).同时,DM组Aa、Tf PCR产物的平均灰度值(average gradation,AVG)比值显著高于CP组,Pi的AVG比值明显低于CP组,P<0.05.结论 与单纯CP相比,伴2型DM的牙周炎患者龈下菌斑中Pg、Aa、Tf的数量增多,Pi的数量减少.     

伴2型糖尿病的慢性牙周炎牙周可疑致病菌的检测

目的 检测伴2型糖尿病(diabetes mellitus,DM)的慢性牙周炎(chronic periodontitis,CP)患者龈下菌斑中牙周可疑致病菌的种类和构成,从微生物学角度探讨牙周炎与DM的相互作用机制.方法 采集伴2型DM的CP患者154例(DM组)、不伴DM的单纯CP患者120例(CP组)及40名全身及牙周健康者(N组)的龈下集合菌斑,传统酚-氯仿法提取菌斑DNA,以牙龈卟啉单胞菌(Porphyromonas gingivalis,Pg),伴放线放线杆菌(Actinobacillus actinomycetemcomitans,Aa),具核梭杆菌(Fusobacterium nucleatum,Fn),中间普氏菌(Prevotella intermedia,Pi),福塞坦氏菌(Tannerella forsythia,Tf),齿垢密螺旋体(Treponema denticola,Td)为目标菌,应用以16SrRNA为基础的聚合酶链反应(PCR)技术对龈下菌群进行检测.结果 Pg、Aa、Fn、Pi、Tf、Td在DM组中均可检出;与CP组相比,在性别、年龄、牙周状况基本一致的情况下,轻度牙周炎者DM组Pi的检出率为35%(8/23),CP组为65%(13/20),两组间差异有统计学意义(P<0.05);重度牙周炎者DM组Pg、Aa、Tf的检出率分别为78%(72/92)、27%(25/92)、67%(62/92),CP组分别为58%(35/60)、17%(10/60)、43%(26/60),DM组均显著高于CP组,差异有统计学意义(P<0.05).同时,DM组Aa、Tf PCR产物的平均灰度值(average gradation,AVG)比值显著高于CP组,Pi的AVG比值明显低于CP组,P<0.05.结论 与单纯CP相比,伴2型DM的牙周炎患者龈下菌斑中Pg、Aa、Tf的数量增多,Pi的数量减少.     

2型糖尿病伴慢性牙周炎患者牙周可疑致病菌的定植研究

目的:研究2型糖尿病伴慢性牙周炎患者龈下菌群的定植,进一步探讨牙周可疑致病菌在慢性牙周炎与2型糖尿病关系中的作用.方法:采集90例重度慢性牙周炎及30例牙周健康的2型糖尿病患者的龈下集合菌斑,以牙周可疑致病菌牙龈卟啉单胞菌(Porphyromonas gingivalis,Pg)、放线共生放线杆菌(Aggregatibacer actinomycetemcomitans,Aa)、具核梭杆菌(Fusobacterium nucleatum,Fn)、中间普氏菌(Prevotella intermedi,Pi)、福塞坦氏菌(Tannerella forsythia,Tf)、牙垢密螺旋体(Treponema denticola,Td)为目标菌,应用以16S rRNA为基础的聚合酶链反应(PCR)技术对龈下菌群进行检测,并测定PCR产物电泳条带的灰度值,以计算各种细菌在菌斑中所占的比例.采用t检验、x2检验、Pearson相关等统计方法,分析患者空腹(FBG)及糖耐量实验2h血糖(OGTT 2h BG)水平,血浆总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)及低密度脂蛋白胆固醇(LDL-C)水平与细菌种类和细菌在菌斑中所占比例的关系.结果:Tf阳性患者的TC水平显著高于阴性患者,Tf在菌斑中所占比例与空腹血糖水平显著正相关,P=0.002;Pg在菌斑中所占比例与TC显著正相关,P=0.035;Pi在菌斑中所占比例与空腹血糖和血浆总胆固醇(TC)水平显著负相关,P分别为0.003、0.041.结论:2型糖尿病对某些牙周可疑致病菌的定植有一定影响.     

伴2型糖尿病的慢性牙周炎牙周可疑致病菌的检测

目的 检测伴2型糖尿病(diabetes mellitus,DM)的慢性牙周炎(chronic periodontitis,CP)患者龈下菌斑中牙周可疑致病菌的种类和构成,从微生物学角度探讨牙周炎与DM的相互作用机制.方法 采集伴2型DM的CP患者154例(DM组)、不伴DM的单纯CP患者120例(CP组)及40名全身及牙周健康者(N组)的龈下集合菌斑,传统酚-氯仿法提取菌斑DNA,以牙龈卟啉单胞菌(Porphyromonas gingivalis,Pg),伴放线放线杆菌(Actinobacillus actinomycetemcomitans,Aa),具核梭杆菌(Fusobacterium nucleatum,Fn),中间普氏菌(Prevotella intermedia,Pi),福塞坦氏菌(Tannerella forsythia,Tf),齿垢密螺旋体(Treponema denticola,Td)为目标菌,应用以16SrRNA为基础的聚合酶链反应(PCR)技术对龈下菌群进行检测.结果 Pg、Aa、Fn、Pi、Tf、Td在DM组中均可检出;与CP组相比,在性别、年龄、牙周状况基本一致的情况下,轻度牙周炎者DM组Pi的检出率为35%(8/23),CP组为65%(13/20),两组间差异有统计学意义(P<0.05);重度牙周炎者DM组Pg、Aa、Tf的检出率分别为78%(72/92)、27%(25/92)、67%(62/92),CP组分别为58%(35/60)、17%(10/60)、43%(26/60),DM组均显著高于CP组,差异有统计学意义(P<0.05).同时,DM组Aa、Tf PCR产物的平均灰度值(average gradation,AVG)比值显著高于CP组,Pi的AVG比值明显低于CP组,P<0.05.结论 与单纯CP相比,伴2型DM的牙周炎患者龈下菌斑中Pg、Aa、Tf的数量增多,Pi的数量减少.     

Hand instrumentation versus ultrasonic debridement in the treatment of chronic periodontitis: a randomized clinical and microbiological trial

Aim: To compare the effectiveness of scaling and root planing (SRP) with the use of hand instruments to that of non-surgical treatment with the use of an ultrasonic device, using clinical and microbiological criteria.
Material and Methods: Thirty-three patients with chronic periodontitis participated in this randomized-controlled clinical trial divided into two groups. Patients in the control group received SRP with hand instruments, whereas patients in the test group received ultrasonic debridement (UD). Clinical recordings concerning probing pocket depth, clinical attachment level, plaque index and gingival bleeding index were performed at baseline, 3 and 6 months after baseline. Subgingival samples were analysed using the "checkerboard" DNA–DNA hybridization technique for Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Tannerella forsythia and Treponema denticola .
Results: Both treatments resulted in a significant improvement in all clinical recordings. Three months after treatment, a numerical decrease was observed for P. gingivalis, T. forsythia and T. denticola in both groups, which was statistically significant only for P. gingivalis ( p <0.05). Inter-group differences were observed at 6 months for T. forsythia and T. denticola ( p <0.05), favouring SRP.
Conclusions: Both treatment modalities provided comparable clinical results in the treatment of chronic periodontitis.     

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。     

Association of Eubacterium nodatum and Treponema denticola with human periodontitis lesions

BACKGROUND: The purpose of the present investigation was to compare the levels, proportions and percentage of sites colonized by 40 bacterial species in subgingival plaque samples from periodontally healthy subjects and patients with chronic periodontitis to seek possible pathogens other than the consensus pathogens Porphyromonas gingivalis and Tannerella forsythia. METHOD: Subgingival plaque samples were taken from the mesial aspect of each tooth in 635 subjects with chronic periodontitis and 189 periodontally healthy subjects. The samples were individually analyzed for their content of 40 bacterial species using checkerboard DNA-DNA hybridization (total samples = 21,832). Mean counts, % DNA probe counts and percentage of sites colonized at >10(5) were determined for each species in each subject and then averaged in each clinical group. Significance of difference between groups was determined using the Mann-Whitney test. Association between combinations of species and periodontal status was examined by stepwise logistic regression analysis. Analyses were repeated using a subset of subjects from both clinical groups who had proportions of P. gingivalis plus T. forsythia less than the median (4.42%) found in periodontally healthy subjects. All analyses were adjusted for multiple comparisons. RESULTS: For the 824 subjects the consensus pathogens P. gingivalis and T. forsythia as well as Eubacterium nodatum and Treponema denticola had significantly higher mean counts, proportions and percentage of sites colonized in samples from subjects with periodontitis than from periodontally healthy subjects. There were significantly more Capnocytophaga gingivalis, Streptococcus gordonii and Veillonella parvula in periodontally healthy subjects. E. nodatum, T. denticola, Streptococcus oralis, Streptococcus intermedius, Fusobacterium nucleatum ssp. vincentii all had higher counts and proportions in diseased than healthy subjects who had low proportions of P. gingivalis and T. forsythia. Logistic regression analysis indicated that the same species groups were associated with disease status after adjusting for the proportions of the other species. CONCLUSIONS: This investigation confirmed the strong association of P. gingivalis and T. forsythia with chronic periodontitis and emphasized a strong association of E. nodatum and T. denticola with periodontitis whether in the presence or absence of high levels of the consensus pathogens. Other species, including S. oralis, Eikenella corrodens, S. intermedius and F. nucleatum ssp. vincentii, were associated with disease when P. gingivalis and T. forsythia were present in low proportions.     

光动力疗法对慢性牙周炎龈下牙周致病菌的影响

目的：应用PeriowaveTM光动力杀菌系统对慢性牙周炎患者进行治疗,通过龈下菌斑中牙周致病菌比例的变化,评价光动力疗法（photodynamic therapy,PDT）治疗慢性牙周炎的临床效果。方法：选取60名慢性牙周炎患者,分别给予SRP＋1次PDT（A组）、SRP＋2次PDT（B组）或单纯SRP（C组）治疗。利用real-time PCR技术检测A、B、C三组在治疗前、治疗后6周、治疗后12周龈下菌斑中牙周致病菌P.g、A.a、T.f所占比例的变化。结果：治疗后6周,A、B两组牙周致病菌P.g在总菌中的比例都有非常显著降低（p〈0.01）,C组有显著降低（p〈0.05）;治疗后12周,A、B组仍有非常显著的降低（p〈0.01）,与C组相比有非常显著差异（p〈0.01）,但A、B两组之间没有差异（p〉0.05）;而仅在治疗后12周,B组的A.a相对于总菌的比例与基线相比有显著降低（p〈0.05）,且这一变化显著大于A、C两组（p〈0.05）;在治疗后6周,A、B组T.f相对于总菌含量的下降与基线相比,明显大于C组（p〈0.05）,治疗后12周,A、B两组T.f相对于总菌的含量仍有非常显著的下降（p〈0.01）,但A组和B组之间都没有差异。结论：PDT对P.g、A.a和T.f3种牙周致病菌都有杀灭作用,但P.g、T.f对PDT更为敏感,PDT可以作为治疗慢性牙周炎的辅助方法。     

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.     

Red bacterial complex is associated with the severity of chronic periodontitis in a Thai population

Background:  The distribution of periodontal pathogens differs in various geographic locations and racial/ethnic groups. This study investigated the microbiological features of chronic periodontitis (CP) patients in Thailand.
Methods:  Subgingival plaque samples from 20 non-periodontitis subjects, 20 patients with mild CP, and 20 patients with moderate to severe CP were examined using polymerase chain reaction (PCR) to identify Porphyromonas gingivalis , Tannerella forsythia , Treponema denticola , and Aggregatibacter actinomycetemcomitans .
Results:  In the moderate to severe CP patients, there was high prevalence of P. gingivalis (95%), T. forsythia (95%), T. denticola (80%), as well as the red complex (coexistence of all three species at the same lesion) (75%). A. actinomycetemcomitans was detected in only 35% of the patients in this study group. P. gingivalis was detected in as high as 45% of the non-periodontitis controls. CP and disease severity were significantly related to the presence of T. forsythia together with T. denticola and the red complex. The red complex was not found in any non-periodontitis site.
Conclusion:  Red complex bacteria were predominant periodontal pathogens of the moderate to severe form of CP in this Thai population. The presence of T. forsythia together with T. denticola , and the red complex species at the same site were significantly associated with the disease severity.     

Microbial flora of periodontitis and monitoring of the effect of initial preparation by immunofluorescence microscopy

The effect of initial preparation in adult periodontitis was evaluated by changes in clinical parameters and immunofluorescence microscopic counts of periodontal disease associated bacteria. Subgingival plaque samples were taken with sterilized paper points from 10 sites of 5 periodontally healthy persons and 44 sites of 23 adult periodontitis patients. Twenty-one diseased sites were periodically examined after plaque control and scaling, root planing. The direct immunofluorescence technique was used to detect Bacteroides gingivalis, Eikenella corrodens, Fusobacterium nucleatum and Treponema denticola, Bacteroides intermedius, Actinobacillus actinomycetemcomitans, Bacteroides forsythus and Wolinella recta were counted by the indirect immunofluorescence technique. The proportions of B. gingivalis, B. forsythus, F. nucleatum, E. corrodens, T. denticola and W. recta in periodontitis lesions were significantly higher than those in healthy sites. The proportions of B. gingivalis and T. denticola were significantly related to GI, PlI, BI and PD, those of B. forsythus and W. recta to GI, PlI and BI, E. corrodens to GI and PlI, and F. nucleatum to BI. Reduced proportions of T. denticola were found in samples taken after establishment of proper plaque control. Subgingival scaling and root planing resulted in the reduction of proportions of B. gingivalis, E. corrodens, T. denticola and B. forsythus in the samples. The samples from positive bleeding sites contained higher proportions of B. gingivalis, T. denticola, B. forsythus and W. recta than did resolved sites. The present study shows that the immunofluorescence technique which detects B. gingivalis, T. denticola and B. forsythus is useful in monitoring the efficacy of initial preparation.     

Changes in subgingival microflora and humoral immune response following periodontal therapy

OBJECTIVES: To investigate the effect of scaling and root planing (SRP) on the microflora and humoral immune response in adult periodontitis. MATERIALS & METHODS: Clinical measurements, subgingival plaque samples, gingival crevicular fluid and sera were taken from 4 sites in 28 adult periodontitis patients before and after SRP. Polymerase chain reaction was used to determine the presence of A. actinomycetemcomitans, P. gingivalis, B. forsythus, P. intermedia, and T. denticola. ELISA was used to investigate the systemic and local antibody titres to these organisms, and thiocyanate dissociation for the determination of serum antibody avidity. RESULTS: SRP produced a good clinical improvement. On a subject basis there was little significant change in the microflora. However, on a site basis, there were significant reductions in P. intermedia, B. forsythus and T. denticola. There was little change in systemic and local antibody titres following SRP, although there was a significant reduction in antibody avidity to P. gingivalis and P. intermedia CONCLUSION: Post-therapy clinical improvement was associated with a reduction in bacterial prevalence, but statistical significance was only reached at a site level and this microbial reduction was not significant for all organisms. No significant post-therapy effects on the humoral immune response were noted other than a reduced antibody avidity to P. gingivalis and P. intermedia. The lack of a clear pattern in the humoral immune response may reflect a failure of the host response to produce adequate levels of biologically functional antibodies, and complex interactions between the subgingival flora and the host response.     

Ⅱ型糖尿病合并牙周炎患者龈下菌斑微生物群落分析

目的：本研究旨在比较Ⅱ型糖尿病合并慢性牙周炎患者与无糖尿病的牙周炎患者龈下菌斑微生物构成。方法：12名患者分为糖尿病合并慢性牙周炎组（T2DM＋CP组）与慢性牙周炎组（CP组）2组,各6人。记录所有患者基本信息及牙周临床参数,包括年龄、性别、探诊深度和附着丧失。根据探诊深度和附着丧失取患病位点的菌斑样本。PCR检测7种牙周可疑致病菌。采用DGGE分离扩增的16SrDNA片段。结果：两组结果显示两组牙周参数无显著差异。两组7种细菌检出率相似。所有对象中均检出牙龈卟啉单胞菌、福塞坦氏菌、齿垢密螺旋体和中间普氏菌,而具核梭杆菌在两组中均有一个样本未检出。变黑普氏菌在T2DM＋CP组的2个样本中检出,而CP组有4个样本检出。伴放线共聚菌在所有样本中均未检测到。DGGE分析结果示两组间条带数量及树状聚类分析均无显著差异。结论：Ⅱ型糖尿病合并牙周炎患者龈下菌斑的牙周可疑致病菌的检出情况以及DGGE分析与无糖尿病患者相似。