Subgingival microorganisms and bacterial virulence factors in periodontitis

Considerable information has come forth in recent years on the pathogenic organisms in human periodontilis and the sequence of events by which they produce periodontal disease. Important pcriodontopatliogens include Bactcroidcs gingivalis, Bactcroidcs intcnnedius and Actinobacillus actinomycetemcomitans. Virulence factors of B. gingivalis and B. intermcdius may mainly involve enzymes with potential to interfere with host defenses and to disintegrate periodontal tissues. Pathogenic properties of A. actinomycetemcomitans appear predominantly to be exerted by leukotoxin and other noxious products.     

Subgingival microorganisms and bacterial virulence factors in periodontitis

Considerable information has come forth in recent years on the pathogenic organisms in human periodontitis and the sequence of events by which they produce periodontal disease. Important periodontopathogens include Bacteroides gingivalis, Bacteroides intermedius and Actinobacillus actinomycetemcomitans. Virulence factors of B. gingivalis and B. intermedius may mainly involve enzymes with potential to interfere with host defenses and to disintegrate periodontal tissues. Pathogenic properties of A. actinomycetemcomitans appear predominantly to be exerted by leukotoxin and other noxious products.     

Subgingival distribution of periodontal pathogenic microorganisms in adult periodontitis.

The association between specific plaque microorganisms and periodontal diseases has been the subject of much recent interest due to its potential importance in the diagnosis and classification of these diseases. In order to optimize microbiological tests in periodontal therapy, it is important to know how many subgingival plaque samples must be assayed from a single patient in order to ascertain infection with a periodontal pathogen. To answer this question the present study assessed the distribution of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Bacteroides forsythus, and Prevotella intermedia in multiple subgingival plaque samples. The samples were quantitatively assessed for specific bacteria by indirect immunofluorescence, a technique previously found to correlate well with cultural assessment of these same organisms. Subgingival plaque from the mesial pockets/sulci of all teeth except third molars was sampled in 12 patients with adult periodontitis, 22 to 28 sites/patient for a total of 315 samples. These patients demonstrated an average mesial probing depth and loss of attachment of 3.7 +/- 1.2 mm and 3.1 +/- 1.5 mm, respectively (mean +/- SD). P. gingivalis, P. intermedia, and B. forsythus were demonstrated in one or more sites from all patients, while A. actinomycetemcomitans was found in one or more sites in 8 of 12 patients. The proportion of positive sites per subject varied, but it was, on average, similar for the 3 black-pigmented organisms and ranged from 44% to 54%. In contrast, A. actinomycetemcomitans was identified, on average, in only 11.4% of the sites in these same patients.(ABSTRACT TRUNCATED AT 250 WORDS)     

牙周炎患者牙周袋内硫化物水平与牙周临床指标的相关分析

目的评价牙周炎患者牙周袋内硫化物（pS）与口气挥发性硫化物（VSC）及牙周临床指标的相关性。方法全口洁治后1周，对20例慢性牙周炎伴口臭的患者龈下刮治和根面平整（SRP）前后用Halimeter检测口气中VSC，用金刚探针检测pS，并对牙周袋内pS及菌斑指数、出血指数、探诊深度、临床附着水平纵向观察6个月。结果口内pS〉0的位点数（r=0．592，P〈0．001）和ps值（r=0．506，P〈0．001）与口气VSC均呈显著正相关；治疗后6周、3个月、6个月，pS与出血指数呈低度相关，r值分别为0．183、0．411、0．350（P〈0．05）；SRP后6周，pS及各临床指标较基线水平显著改善（P〈0．001），并在第3、6个月时进一步改善或保持稳定。结论pS值可以特异性地反映牙周袋内硫化物的水平，可作为牙周疗效判断的客观指标，反映和监测维护期的牙周组织炎症状况。     

Subgingival microflora in Turkish patients with periodontitis

BACKGROUND: No information exists on periodontitis-associated subgingival microbiota from Turkey. We determined the occurrence, interspecies relationships, and clonal characteristics for a group of periodontal bacteria in a Turkish study population. METHODS: Subgingival microbial samples were obtained from patients with localized (LAgP, N = 18) or generalized (GAgP, N = 17) types of aggressive periodontitis, generalized chronic periodontitis (GCP, N = 14), and non-periodontitis subjects (N = 20). Culture methods were used to recover 6 periodontal bacterial species and yeasts, and a polymerase chain reaction technique was used to detect Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis. Intraspecies characterization of A. actinomycetemcomitans was carried out by serotyping and genotyping. RESULTS: All species, except for Micromonas micros (formerly Peptostreptococcus micros) occurred more frequently (P < 0.05) in periodontitis than non-periodontitis subjects. Detection frequencies for Tannerella forsythensis (formerly Bacteroides forsythus) and Campylobacter rectus differed among the periodontitis subgroups; the lowest frequency occurred in LAgP. The mean proportions of A. actinomycetemcomitans, P. gingivalis, and C. rectus were higher (P < 0.008) in GAgP than in non-periodontitis subjects. Significant positive associations were seen between 7 of the 22 possible combinations (P < 0.05). A. actinomycetemcomitans serotype c (34%) and non-serotypeable isolates (34%) were the most common antigenic types among the 305 strains analyzed. Eleven arbitrarily primed (AP)-PCR genotypes were distinguished among 273 isolates from 29 subjects. Yeasts were found in 23% of the 69 subjects. CONCLUSIONS: The results on the Turkish study population were generally in line with earlier reports on the occurrence and interspecies relationships of certain bacteria in periodontitis. However, A. actinomycetemcomitans was not overrepresented in LAgP, and the serotype distribution resembled that reported from the East. The high frequency of non-serotypeable isolates suggests local characteristics of the species.     

Subgingival microbial consortia and the clinical features of periodontitis in adolescents

This study aimed to investigate the association between microbial consortia and the clinical features of periodontitis using a multilevel modeling approach. A total of 958 sites in 87 adolescents with periodontitis (cases) and 73 controls were microbiologically sampled and clinically examined. Associations between each of the clinical parameters clinical attachment, probing depth, supragingival plaque, calculus, bleeding on probing, and each of 18 bacterial species; and between the same clinical parameters and each of two microbial consortia identified, were investigated using mixed-effects regression modeling. Higher counts of Tannerella forsythia, Campylobacter rectus, and Porphyromonas gingivalis were all statistically significantly associated with higher values of clinical attachment level, probing depth, and bleeding on probing in the sampled site, when both case status and between-subject variance were accounted for. Higher counts for the consortium comprising the putative periodontopathogens were statistically significantly associated in a dose-response manner with both higher clinical attachment levels and with increased pocket depth. The counts for the consortium predominantly comprising the early-colonizer species were statistically significantly negatively associated with the presence of supragingival calculus, but positively associated with the presence of supragingival plaque. The study demonstrates a relationship between the counts of putative periodontopathogens and clinical attachment levels and probing pocket depths, even for low levels of these clinical parameters.     

Juvenile periodontitis – pattern of progression and relationship to clinical periodontal parameters

Abstract – The present investigation was carried out 1) to identify subjects with juvenile periodontitis (JP) in a group of schoolchildren from a community with a high prevalence of periodontal diseases and with no access to preventive dental care, and 2) to study the clinical features of the disease and the progression pattern during a period of 1 yr, and the relationship of JP to clinical periodontal parameters. The periodontal condition of a group of 502 Iraqi schoolchildren (260 girls and 242 boys) was assessed radiographically and clinically at baseline. Children showing 3 mm arc-shaped angular radiographic bone loss at the proximal surfaces of two or more first molars and who showed clinical attachment loss at the same sites were regarded as JP patients. A second group of children with no signs of JP were randomly chosen from the study material. One year later, the JP and the non-JP groups were re-examined radiographically and clinically to assess plaque, gingivitis and presence of calculus. The results showed that nine children (1.8%) had JP. The ratio of girls to boys was 3.5:1, and of localized to generalized forms 2:1. Mesial surfaces of first molars were more often affected than distal surfaces. Clinical assessments showed a more profound loss than was depicted radiographically. All JP patients exhibited evidence of periodontal disease progression during the following year. There were no differences between JP and non-JP children with respect to gingival inflammation, dental plaque, or calculus deposits on teeth. It was concluded that the present findings are consistent with the view that plaque and plaque-retaining factors may predispose to the high rate of periodontal support loss usually seen in JP patients.     

Subgingival temperature and microbiota in initial periodontitis

Abstract. The association between subgingival temperature, other clinical characteristics, and the subgingival microbiota was examined in adult subjects with initial periodontitis and differing levels of gingival inflammation, 43 subjects were measured at 6 sites per tooth for pocket depth, attachment level, presence of plaque, gingival redness, bleeding on probing and subgingival temperature at 3-month intervals for 1 year. Subgingival plaque was sampled from 15 initial active periodontitis sites (10 subjects), 121 gingivitis, sites (20 subjects) and 202 healthy sites (13 subjects), and included the 5 hottest and 5 coldest sites in each subject. Plaque samples were analyzed for 13 subgingival species using whole-genomic DNA probes. The major influences on the subgingival microbiota were the clinical status of sites, pocket depth, and the presence of supragingival plaque. No significant association between species and site temperature was observed. Initial active sites were associated with Bacteroides forsythus and Campylobacter rectus. and had a higher mean subgingival temperature and deeper mean pocket depth than inactive sites, A weak association between pocket depth and site temperature was noted. The major influence on subgingival temperature of sites was the anterior to posterior anatomical temperature gradient in the mandible and maxilla.     

Subgingival temperature in smokers and non-smokers with periodontal disease

Abstract The purpose of this study was to compare subgingival temperature in a group of smokers to that of a group of non-smokers with similar levels of periodontal disease. 40 adult subjects. 20 cigarette smokers and 20 non-smokers with evidence of adult periodontitis were examined. Subgingival temperature was measured at 6 sites around each of 4 maxillary anterior teeth. Probing depth, and the presence or absence of bleeding was also recorded. In addition, the sublingual temperature was recorded. All sites were classified as diseased or healthy. Healthy sites did not bleed and had a probing depth of ≥ 4mm. diseased sites were any site which had a probing depth ≥ 5 mm. or which bled on probing. Mean sublingual and site temperatures were calculated for smokers and non-smokers. Mean temperature differentials (ΔT) between the sublingual temperature and the site temperature were calculated for each site. Smokers had a warmer mean sublingual temperature than non-smokers. A significant difference in subgingival site temperature was demonstrated between the smokers and non-smokers, with the mean site temperature being 0.4°C warmer in smokers (p < 0.01). When healthy or diseased sites were compared between smokers and non-smokers, smokers also had warmer mean site temperatures than non-smokers for both healthy and diseased sites (p < 0.01). When the mean temperature differentials (ΔT) between healthy and diseased sites were compared across each group, significant differences were also found. For healthy sites, the smokers had a mean ΔT 0.2°C lower (p < 0.01) than the non-smokers, representing warmer sites. In diseased sites however. ΔT was 0.3°C higher (p < 0.01) in smokers, representing cooler sites.     

Crevicular fluid level of β-glucuronidase in relation to clinical periodontal parameters and putative periodontal pathogens in early-onset periodontitis

Abstract. Analysis of β-glucuronidase (βG) in the gingival crevicular fluid (GCF) provides an indication of neutrophil influx into the crevicular environment. The aim of this study was to test the hypotheses that: (1) βG is significantly elevated in individuals with early-onset periodontitis (EOP) and that βG activity correlates with disease severity: and (2) βG level may reflect the local bacterial challenge in the gingival crevice. The study subjects consisted of a sub-sample of individuals examined in the National Survey of Oral Health of United States Children, which was undertaken during the 1986/87 school year. A total of 249 individuals were selected based on presence or absence of clinical attachment loss at baseline. The individuals were examined a second time 6 years later and the clinical attachment loss was assessed, and subgingival plaque and GCF were collected. The subjects were classified into 3 types of EOP and a control group, βG activity in the GCF and the levels of 7 putative micro-organisms in the pocket were assessed. The generalized EOP group had the highest βG activity, followed by the localized and incidental EOP groups, and the controls, respectively. There was a significant increase in βG activity with the increase in probing depth. Also, sites with bleeding on probing had a significantly higher βG activity than sites without bleeding. However, the effect of gingival inflammation on βG activity was more evident in the generalized and localized EOP groups. Sites harboring high levels of one or more of the micro-organisms tended to have high βG activity. There were moderate differences between the organisms with respect to their effect on βG activity, but sites with high numbers of Porphyromonas gingivalis, Prevotella intermedia, or Treponema dentieola also had the highest βG activity. The present findings suggest that βG activity in GCF from patients with EOP can be of value in the early identification of individuals at higher risk of developing EOP, The findings also suggest that host mechanisms leading to higher βG activity in EOP represent systemic responses and are only partly related to the presence of local factors at the site-level.     

不同牙周状态下龈下菌斑中人类巨细胞病毒的检测

目的 :研究人类巨细胞病毒 (HCMV)与慢性牙周炎及其活动性的相关性。方法 :采集 62例慢性牙周炎患者 (男性 2 7例 ,女性 3 5例 )的牙周炎活动部位 ,牙周炎静止部位 ,以及轻度龈炎部位的龈下菌斑 ,使用SeekVi ralDNAkit试剂盒提取DNA ,采用巢式PCR法检测HCMV ,比较同一患者不同牙周状态的检出率并加以分析。结果 :慢性牙周炎患者牙周炎活动部位、牙周炎静止部位、轻度龈炎部位的HCMV检出率为分别为 3 8.7%、14 .5 %、12 .9% ;HCMV在牙周炎活动部位的检出率高于牙周炎静止期部位 (P <0 .0 5 ) ,以及轻度龈炎部位 (P <0 .0 5 ) ;牙周炎静止部位与轻度龈炎部位的HCMV检出率的差异无统计学意义 (P >0 .0 5 )。结论 :提示HCMV感染与慢性牙周炎及其活动性的有一定的相关性。     

慢性牙周炎患者的龈下微生物与吸烟状况

目的　评价慢性牙周炎患者的吸烟状况与龈下牙周致病微生物的百分比。方法　 112例慢性牙周炎患者 ,根据吸烟状况分为 :①重度吸烟组 >10支 /天 (n =32 ) ;②轻度吸烟组≤ 10支 /天 (n =18) ;③戒烟者组 (n =2 4 ) ;④非吸烟组 (n =38)。观察者口内每个象限 ,选取探诊最深的 1或 2个位点 ,纸捻法取龈下菌斑 ,厌氧培养 ;并测量该位点的探诊深度 (ProbeDepth ,PD)、附着丧失 (AttachmentLoss,AL)和探诊后出血 (Bleedingofprobe ,BOP)。结果　①取样位点临床指标的均值为PD :6 .3mm、AL :6 .5mm及BOP :89% ,各组间无显著性差异。②组间菌落形成单位和龈下微生物伴放线放线杆菌 (Actinobacillusactinomycetemcomitans,A .a)、牙龈卟啉单胞菌 (Porphyromanasgingivalis,P .g)、中间普氏菌 (Prevotellaintermedia ,P .i)、核梭杆菌 (Fusobacteriumnucleatum ,F .n)和微消化球菌(Peptostreptococcusmicros,P .m)的百分比均无差异。③方差分析显示仅轻度吸烟组福赛类杆菌 (Bacteroidesforsythus,B .f)的百分比略高于其它组 (P <0 .0 4 )。结论　慢性牙周炎患者 ,探诊深度和附着丧失相似的位点 ,吸烟组、戒烟组和非吸烟组的龈下牙周致病微生物百分比 (B .f除外 )无显著差异。     

Subgingival Epstein-Barr and cytomegalovirus occurrence in pregnancy gingivitis

Background: Although recent studies focused on the role of human herpesviruses in various types of periodontal disease, there was a lack of information in these reports regarding the role of pregnancy gingivitis. The aim of this study is to determine the correlation between pregnancy and the subgingival virus presence and their relationship with clinical parameters. Methods: Seventy pregnant and 40 non‐pregnant women were examined for gingival and plaque indices, bleeding on probing (BOP), and clinical probing depths (PDs) from the whole dentition. Subgingival plaque samples were obtained from sites showing signs of gingivitis and healthy sites. The polymerase chain reaction methodology was used to detect cytomegalovirus (CMV) and Epstein‐Barr virus (EBV) from plaque samples. Results: Our results show that gingivitis lesions in 27 (38.6%) and 10 (14.3%) pregnant patients were positive for EBV and CMV, respectively. In the non‐pregnant group, EBV and CMV were detected in six (15%) and eight (20%) lesions, respectively. A statistically significant difference (P <0.01) was found between the subgingival occurrence of EBV in the two groups. In gingivitis sites, clinical PDs were affected by gestation (P <0.001) and the occurrence of EBV (P <0.001). In healthy sites, clinical PDs were affected by gestation (P <0.05), and BOP was affected by the occurrence of CMV and EBV (P <0.001). Conclusion: Our data indicate that pregnancy increased the risk of the presence of subgingival EBV in pregnant women by 3.647 times more than in non‐pregnant women.     

人巨细胞病毒与牙周炎相关性的研究进展

牙周炎是病因复杂的炎症破坏性疾病,其发病与微生物、宿主和环境等多种因素有关.牙周炎的病因及发病机制目前未完全明了.近年来,国内外学者发现人巨细胞病毒与多种类型牙周炎的发生和发展存在一定的相关性.本文就该病毒与牙周炎的相关性及在牙周炎发病中的机制进行综述.     

Effects of scaling and root planing on clinical parameters and bacterial flora in periodontal pockets. 1. Changes in clinical parameters and subgingival bacterial flora after treatment

The purpose of this study was to clinically and microbiologically evaluate the effects of supragingival plaque control, scaling and root planing on periodontal therapy. Six patients affected with moderate or severe periodontitis were selected. The clinical status of each patient was recorded with such clinical parameters as probing pocket depth (PD), probing attachment level (PAL), gingival crevicular fluid flow (GCF), gingival index (GI), gingival bleeding index (GBI), suppurative index (SI), and mobility (Mo). After the patients had learned to perform their own oral prophylaxis, they were treated by scaling and root planing. Microbiological status was assessed by phase contrast microscopy and bacterial forms were classified into following six groups: coccoid cells, rods, filaments, fusiforms, motile rods, spirochetes. The number and the relative proportion of each group were compared statistically. Clinical and microbiological status from baseline to 5 months after scaling and root planing were re-examined. The results obtained were as follows. 1. The most significant change in clinical and microbiological status was observed one month after scaling and root planing. In particular, the total number of the microorganisms and the number and relative proportion of motile organisms were reduced. 2. Thereafter clinical and microbiological status was maintained during experimental period by means of supragingival plaque control.