Prevalence of suspected periodontal pathogens identified using ELISA in adolescents of differing ethnic origins

Abstract The aim of this study was to determine the prevalence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia in a group of adolescents and investigate the association of these organisms with various clinical parameters. A total of 527, 11-13-year-old children, of whom 333 (63%) were white Caucasian, 187 (35%) Indo-Pakistani and 7 (1%) Afro-Caribbean, participated in the study. Subgingival plaque samples, collected from the mesio-buccal of both upper first permanent molars using sterile paper points, were stored in phosphate buffered saline with 0.01% thiomersal and analysed for the presence of A. actinomycetemcomitans, P. gingivalis and P. intermedia using ELISA. The mesio-buccal sites of both upper 1st permanent molars were also examined and the presence/absence of supragingival plaque, subgingival calculus, bleeding on probing and pocket depths greater than 3 mm were recorded. The % of white Caucasian children in whom the monoclonal antibody identified at least 1 site with A. actinomycetemcomitans, P. gingivalis and P. intermedia were 4%, 3% and 2%, respectively, and for Indo-Pakistanis were 3%, 17% and 2%. The difference for P. gingivalis was statistically significant (p < 0.001). The associations between the clinical parameters and the 3 organisms were considered separately for both upper first molar sites. The prevalence of P. gingivalis was higher for sites with subgingival calculus, pockets >3 mm and bleeding on probing (p < 0.001).     

Occurrence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia in juvenile periodontitis

Abstract The occurrence of Actinobacillus actinomycetemcomitans, Porphyromanas gingivalis and Prevotella intermedia in subgingival plaque in 24 juvenile periodontitis patients was determined using DNA probe. 36 samples of subgingival plaque from 36 pockets having ≥6 mm depth, ≥3 mm of loss of attachment, and Weeding on probing anchor suppuration were taken from 18 patients with localized juvenile periodontitis (LJP, age range 12-24 years); and 12 samples from-6 patients with generalized juvenile periodontitis (GJP, age range 23–26 years). As control, an equal numbers of samples from health sites in the same patients were studied. P. gingivalis was found in 17 of 18 LJP patients, and in 31 of 36 diseased sites in those patients. P. intermedia was found in 15 out of the 18 LJP patients and in 28 of the 36 diseased sites. A, actinomycetemcomitans was present in 7 of the 18 LJP patients, and in 9 of the 36 diseased sites, and was not found in any GJP patients. All GJP patients had P. gingivalis 1 out of 12 diseased sites) and P. intermedia (all of the diseased sites). None of the three bacterial species was detected in healthy sites of GJP patients, and were found in healthy sites in only 2 of 18 LJP patients. The high prevalence and high levels of P. gingivalis and P. intermedia found in the LJP and GJP patients studied, suggest that there are populations affected by juvenile periodontitis in which this type of periodontitis is more associated with these species than with A. actinomycetemcomitans.     

Subgingival temperature: relation to gingival crevicular fluid enzymes, cytokines, and subgingival plaque micro-organisms

Abstract There have been no reports on the relationship of subgingival temperature to specific gingival crevicular fluid (GCF) components. Therefore, the purpose of this cross-sectional study was to determine whether there was any relationship between subgingival temperature and GCF levels of neutrophil elastase (NE), myeloperoxidase (MPO), beta-glucuronidase (BG), interleukin-1 α (IL-l), and interferon α (IFN). Furthermore, another objective was to confirm an association of subgingival temperature with clinical parameters and specific subgingival plaque micro-organisms as has been reported earlier. 27 human subjects each having healthy (n=50), gingivitis (n=59) and periodontitis (n=53) sites were evaluated. The plaque index (PI), subgingival temperature, probing depth, attachment loss, bleeding index and gingival index were measured. GCF was sampled following the measurement of the PI and removal of the supragingival plaque. GCF samples were assayed for the enzymes NE, BG, MPO and the cytokines IFN-α and IL-1 α. A sterile Gracey curette was utilized at each sampled site to collect subgingival plaque. The plaque samples were evaluated using an immuno-assay. Subgingival temperature was found to directly correlate with all clinical parameters (p<0.001). Significant, albeit not large, correlations were found between subgingival temperature and NE (r= 0.35, p<0.001), MPO (r= 0.26, p<0.001)and BG (r= 0.23, p<0.01). Temperature was found to correlate positively with E. corrodens (r= 0.33, p<0.02) and F. nucleatum (r= 0.25, p<0.05) but not with P. intermedia (r= 0.02, p= 0.9), P. gingivalis (r= 0, 20, p=0.1) and A. actinomycetemcomitans (r=0.01, p0.9). In conclusion, subgingival temperature is correlated with the GCF enzymes, NE, MPO and BG as well as the clinical parameters and specific plaque micro-organisms associated with periodontal disease.     

Site progression of loss of attachment over 5 years in 14-to 19-year-old adolescents

Abstract The aims of this study were (1) to monitor the progression and patterns of progression of loss of attachment ≥1 mm on a site basis over a 5-year period in adolescents, and (2) to relate the presence of oral deposits and inflammation to the subsequent development and progression of loss of attachment on a site basis. 167 subjects were examined at ages 14, 16 and 19 years. Loss of attachment ≥1 mm, plaque, subgingival calculus, gingival bleeding and gingival colour change were assessed on the mesiobuccal sites of the 1st molars, 1st premolars and central incisors. Each site was treated separately in the analysis to avoid the problem of within-subject site dependence. Sites were classed as progressing, non-progressing or fluctuating according to the probing attachment level measurements at each of the 3 examinations. During the 5 years of this study, a total of 542 sites in 128 subjects progressed: 1136 sites in 162 subjects did not progress; 43 sites in 30 subjects had fluctuating attachment level measurements. Sites which subsequently progressed had significantly more plaque, subgingival calculus and gingival inflammation than non-progressing sites at the baseline examination and throughout the study (p<0.001). Between 55-57% of the maxillary 1st molars and 46-49% of the mandibular incisors progressed. In contrast, there was no progression of loss of attachment on over 80% of the maxillary central incisors and mandibular 1st premolars.     

Risk indicators for periodontal disease in a racially diverse urban population

Abstract A cross-sectional study of 117 subjects from a dental clinic serving a diverse population (i.e., Whites. African-Americans. Native-Americans, and Asians) was performed to evaluate risk indicators of periodontal disease. Gingival crevicular fluid (GCF) and subgingival plaque were taken at the same visit from 4 posterior sites of the most diseased sextant in each subject. Age, smoking packyears. β-glucuronidase (βG). neutrophil elastase (NE). myeloperoxidase (MPO). Fusobacterium nucleatum (F. nucleatum), and Porphyromonas gingivalis (P. gingivalis) were significantly (p <0.05–0.005) correlated with attachment loss. Probing depth was significantly correlated with smoking packyears, βG, NE, MPO. F. nuclealum and Prevotella intermedia (P. intermedia) (p < 0.05–0.005). Mean NE value of Whites was lower than the mean NE values of African-Americans, Native-Americans and Asians (P < 0.05). Whites had a lower mean βG value compared to African Americans, and a lower mean MPO value compared to African Americans and Native Americans. The %s of patients positive for F. nucleatum. P. intermedia and Eikenella corrodents (E. corrodents) were higher in Native Americans compared to Whites. Step-wise multiple regression analysis was performed to construct models for the estimation of probing depth and attachment loss. The most parsimonious regression models which had the best R ² values included the following variables and accounted for the indicated % of variability: models 1 and 2: βG. race, and F. nucleatum accounted for 50% of the variability in mean probing depth and 39% of the variability in a single site (first molar) for probing depth, respectively: model 3: age. βG. and F. nuclealum accounted for 53% of the variability in mean attachment loss: model 4: age. NE. and F. nuclealum explained 35% of the variability in a single site (first molar) for attachment loss. The results suggest that age. race, smoking packyears, βG, NE. MPO. F. nuclealum, P. gingivalis and P. intermedia are risk indicators for periodontal disease in this racially diverse urban population. Regression models which include multiple variables (i.e., demographic factors, GCF enzymes and periodontopathic bacteria) can be used to estimate periodontal disease status.     

Natural distribution of 5 bacteria associated with periodontal disease

Abstract The purpose of this study was to determine the prevalence and distribution of 5 bacterial pathogens in subgingival plaque, their relationship with each other and probing depth. Plaque was collected from 6905 sites in 938 subjects. A bacterial concentration fluorescence immunoassay and bacterial specific monoclonal antibodies were used to determine the presence and level of P. gingivalis (Pg), A. actinomycetemcomitans (Aa), P. intermedia (Pi), E. carrodens (Ec) and F. nucleatum (Fn) in each plaque sample. The prevalence in subjects was lowest for Pg (32%) and highest for Ec (49%). The site-based frequency distribution of these bacterial species ranged from 10.3% for Pg to 18.7% for Ec. Pi and Ec were the bacterial combination most often found together in a subject (27.2%). While 64.0% of the sites were without any of the 5 bacterial species evaluated, 20.2% had only 1 of the 5 bacterial species evaluated. The remaining 15.8% of sites had at least 2 bacteria species present. There was a general linear association of the detection level of bacterial species and probing depth. The odds ratios were 3.9 (Pg). 3.0 (Aa), 4.0 (Pi). 2.7 (Ec) and 2.8 (Fn) of finding high levels of these bacterial pathogens at > 5 mm probing depth (p≤ 0.01). Mean probing depth at molar sites without a specific bacteria was greater (p≤ 0.01) in subjects wish a specific bacterium compared to molar sites in subjects without the bacteria. The observation that these 5 bacterial species frequently inhabit the subgingival environment, yet are not associated with advanced disease, suggest that a susceptible host is required, in addition to a “pathogenic bacteria”, before disease progression may occur.     

Actinobacillus actinomycetemcomitans,Capnocytophaga and Porphyromonas gingivalis in subgingival plaque of adolescents with Down's syndrome

Levels of Actinobacillus actinomycetemcomitans, Capnocytophaga and Porphyromonas gingivalis were determined in subgingival plaque samples from 37 adolescents with Down's syndrome and 37 healthy controls matched with respect to age and sex. Gingival inflammation, supra- and subgingival calculus, periodontal pockets (>4 mm) and alveolar bone loss were registered. Alveolar bone loss was more frequent in Down's syndrome subjects (32%) than in the controls (3%). A. actinomycetemcomitans was detected in the subgingival plaque in 35% of the Down's syndrome adolescents and in 5% of the controls. On site level, A. actinomycetemcomitans and Capnocytophaga were more frequent in the subgingival plaque samples of Down's syndrome children than in those of controls. Comparing Down's syndrome subjects positive or negative for A. actinomycetemcomitans and Capnocytophaga, no significant differences were found in terms of gingival inflammation, periodontal pockets (>4 mm) or number of sites with alveolar bone loss. The results indicate an altered microbial composition of the subgingival plaque of Down's syndrome subjects compared with healthy controls, with higher frequency of A. actinomycetemcomitans.     

The effect of plaque control in subjects with shallow pockets and high prevalence of periodontal pathogens

Abstract In a previous study, it was shown that professional tooth cleaning 3X a week had a significant influence on the subgingival microbiota of shallow pockets. The purpose of this investigation was to study the effect of a single episode of full-mouth supragingival cleaning and oral hygiene instructions in subjects with minimal periodontal disease but high prevalence of putative periodontal pathogens. 10 subjects from Arabic countries, aged between 22 and 48 years, which had previously not been exposed to any dental care other than extractions and fillings, were selected for this trial. DNA probe analysis of subgingival samples, taken in the deepest pocket of each quadrant, showed presence of Porphyromonas gingivalis and Prevotella intermedia in all patients, and presence of Actinobacillus actinomycetemcomitans in 5 individuals. 85% of all samples were P. gingivalis-positive, 83% were positive for P. intermedia and 43% were A. actinomycetemcomitans-positive. 4 weeks after treatment, subgingival microbiological samples were again taken in the same sites. In 8 patients. P. gingivalis could still be detected after treatment. However, the number of P. gingivalis positive samples was reduced from 85% to 38%, and the bacterial counts in positive samples were markedly lower than at baseline. P. intermedia-positive samples were obtained from 7 patients after treatment. 33% of all samples were still positive, but showed markedly reduced bacterial counts. 4 patients still yielded A. actinomycetem comitans-positive samples after treatment. Here, the number of positive samples was reduced to 15%, and the bacterial counts were barely exceeding the detection limit. Concomitantly, the % of pockets deeper than 3 mm was reduced from 13% to 3% and the percentage of sites bleeding upon probing was reduced from 68% to 20%. This study demonstrated a considerable, although not maximal clinical and microbiological effect of supragingival plaque control in subjects with high prevalence of periodontal pathogens but minimal periodontal disease.     

Investigation and quantification of key periodontal pathogens in patients with type 2 diabetes

Field CA, Gidley MD, Preshaw PM, Jakubovics N. Investigation and quantification of key periodontal pathogens in patients with type 2 diabetes. J Periodont Res 2012; 47: 470–478. © 2012 John Wiley & Sons A/S Background and Objective: Diabetes is a recognized risk factor for periodontitis. There are conflicting data regarding whether healthy diabetic patients or diabetic patients with chronic periodontitis have an altered subgingival microbiota compared with nondiabetic individuals. The aim of the present study was to detect quantitative differences in selected periodontopathogens in the subgingival plaque of diabetic patients using TaqMan quantitative PCR. Material and Methods:  Type 2 diabetes mellitus patients with (n = 9) or without chronic periodontal disease (n = 15) were recruited and matched to nondiabetic control subjects (n = 12 periodontally healthy, n = 12 chronic periodontitis). Subgingival plaque samples were collected from deep (> 4 mm probing depth) and shallow sites (≤ 3 mm probing depth) using paper points, and Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum and Porphyromonas gingivalis were quantified. Results: Forty‐eight subjects (69 samples) were recruited. Marked differences were seen in the levels of all three bacterial species, relative to the total bacterial population, according to periodontal health status. Using real‐time quantitative PCR, bacterial counts for P. gingivalis were significantly higher in deep pockets of diabetic and nondiabetic subjects compared with periodontally healthy subjects (p < 0.05) but did not differ significantly between diabetics and nondiabetics. A. actinomycetemcomitans was detected in all groups in low quantities, and counts did not differ significantly between groups (p > 0.05). F. nucleatum was abundant in all groups, with no clear significant differences between groups. P. gingivalis was found in higher quantities in periodontitis than in periodontally healthy subjects (p < 0.05). Statistically significant positive correlations were identified between pocket depth and counts for all three species tested (p < 0.05). Conclusion: A. actinomycetemcomitans, F. nucleatum and P. gingivalis were present in significantly different quantities and proportions in subgingival plaque, according to periodontal disease status. No significant differences were identified between the subgingival microbiota of type 2 diabetes mellitus patients compared with nondiabetic subjects.     

Clinical and microbiological changes associated with the use of 4 adjunctive systemically administered agents in the treatment of periodontal infections

Abstract. The purpose of the present investigation was to assess the effects of periodontal surgery and 4 systemically administered agents, Augmentin, tetracycline, ibuprofen or a placebo on clinical and microbiological parameters of periodontal disease, 98 subjects were monitored at 2-month intervals at 6 sites per tooth for clinical parameters. Subgingival plaque samples were taken from the mesial surface of each tooth at each visit and evaluated for their content of 14 subgingival species using DNA probes and a colony lift method. 40 subjects who exhibited loss of attachment >2.5 mm at 1 or more sites during longitudinal monitoring were treated using modified Widman flap surgery at sites with probing pocket depth >4 mm, subgingival scaling at all other sites and were randomly assigned 1 of the 4 agents. Treatment was completed within 30 days during which time the subject took the assigned agent. Overall, subjects exhibited a mean attachment level “gain” of 0.34±0.10 mm (SEM) and a mean pocket depth reduction of 0.62±0.09 mm 10±4 months post-therapy. However, certain subjects in each treatment group showed a poor response. Subjects receiving antibiotics exhibited significantly more attachment level “gain” (0.57±0.15 mm, SEM) than subjects receiving either ibuprofen or a placebo (0.02±0.10). The differences between Augmentin and tetracycline groups were not significant, nor were the differences between ibuprofen and placebo, 10 months post-therapy, there was a reduction in the number of sites colonized in any subject group by detectable levels (10³) of P. gingivalis. Species showing similar reductions were B. foraythus, P. intermedia and P. micros. Subjects receiving systemically administered antibiotics had a significant increase in the proportion of sites colonized by C. ochracea coupled with a greater decrease in the number of sites colonized by P. gingivalis. B. forsythus, P. intermedia and P. micros post-therapy than subjects not receiving antibiotics. The results of this investigation indicate that adjunctive systemic antibiotics increase periodontal attachment “gain” and decrease the levels of some suspected periodontal pathogens in subjects with evidence of current disease progression.     

Short-term effect of full-mouth extraction on periodontal pathogens colonizing the oral mucous membranes

Abstract In this study, we investigate the prevalence of selected periodontal pathogens on the oral mucous membranes before and after full-mouth tooth extractions in patients with severe periodontitis. 8 patients were microbiologically examined 2 × before and 2 × after extraction; several locations on the oral mucous membranes, saliva, supra- and subgingival plaque, were sampled. Besides their presence in subgingival plaque, we detected before extraction on the mucous membranes Actinobacillus actinomycetemcomitans in 2 patients (mean 0.03%), Porphyromonas gingivalis in 6 patients (mean 9%), and Prevotella intermedia (mean 2%) and other Prevotella species (mean 7%) in all patients. At 1 and 3 months after extraction, A. actinomycetemcomitans and P. gingivalis could not be detected in any of these patients on the oral mucous membranes and in saliva, while from all patients still P. intermedia (mean 3%) and the other blackpigmented Prevotella species (mean 4%) could be isolated. These results indicate that the preferable habitat for A. actinomycetemcomitans and P. gingivalis is dental plaque in subgingival lesions. P. intermedia and the other blackpigmented Prevotella species can colonize the oral mucous membranes of edentulous patients irrespective of the presence of a subgingival microflora. We speculate that in periodontal patients the colonization of mucous membranes with P. gingivalis and A. actinomycetemcomitans is transient in nature and most likely the result of dissemination from the subgingival microflora. Thus it seems unlikely that edentulous patients constitute a reservoir of infection of P. gingivalis A. actinomycetemcomitans.     

A relationship between proteinase activity and clinical parameters in the treatment of periodontal disease

Abstract. The objective of this research was to determine the effectiveness of a biochemical assay which measures proteolytic enzyme activity in gingival crevicular fluid (GCF) and to relate this enzyme activity to clinical parameters traditionally utilized for periodontitis detection. A clinical trial was conducted on 8 periodontitis subjects with ≥4 sites exhibiting a loss of attachment of ≥5 mm and probing depths of ≥5 mm with bleeding on probing. On each subject, a plaque index was performed, followed by GCF sampling at those sites which exhibited a loss of attachment and probing depths. GCF was analyzed for activity against benzoyl-L-arginine-p-nitroanilide in the presence (BAPNA w/gly-gly) and the absence (BAPNA w/o gly-gly) of glycyl-glycine and against MeOSuc-Ala-Ala-Pro-Val-pNA and Suc-Ala-Ala-Pro-Phe-pNA for neutrophil serine proteinases activity (elastase and cathepstn G, respectively). Subsequently, a gingival index was performed, attachment levels and probing depths were recorded using a constant force probe with bleeding on probing being noted. A split-mouth design was employed and half mouths were randomly assigned to the following treatment groups: group A, half of the mouth received scaling/root planing and polishing: group B, half of the mouth received no treatment (control). Subjects were treated, then instructed on toothbrushing and interdental cleaning. After 4 weeks, subjects returned to receive a plaque index; GCF sampling, gingival index, attachment levels, probing depths and bleeding on probing as described above. Using a patred Student t-test, the findings suggest that BAPNA w/gly-gly was significantly less in treatment sites than in non-treated control sites (p=0.05). No such correlation was found for other activities, including neutrophil serine proteinases which were shown to occur in GCF in free, proteolytically active forms. In addition, significant treatment effects were detected for probing depths (p= 0.03) which reduced by 1.3 mm and attachment levels (p=0.02) which gained 0.7 mm. The reduction of P. gingivalis from treated periodontitis sites as detected by a significant decrease in BAPNA w/gly-gly may prove to be a valuable marker for periodontal disease activity.     

The effect of sibling relationship on the periodontal condition

Abstract The purpose of this investigation was to study clinically as well as microbiologically the effect of sibling relationship on the periodontal condition in a young population with a relatively high prevalence of periodontal disease and deprived from regular dental care. In this study, 23 family units consisting of 3 more siblings were evaluated. In all, 78 subjects aged 15 to 25 years were included in the study, The mean interproximal amount of Joss of attachment in this population was 0.29 mm. The individual mean ranged from 0 to 1.27 mm. In 33% of the subjects, 1 sites with a probing depth of 5 mm or more in conjunction with 2 mm of attachment loss were present. The results show a significant sibship effect for: plaque, calculus, loss of attachment, spirochetes on the tongue and in the pocket, Porphyromonas gingivalis on the gingiva and in the saliva and Prevotella intermedia in the saliva. These results support the hypothesis that periodontitis aggregates in families.     

Response to periodontal therapy in patients with high or low levels of P. gingivalis, P. intermedia, R nigrescens and B. forsythus

Abstract In a previous study, subjects receiving either adjunctive tetracycline or Augmentin showed, on average, more attachment level gain 10 months post-therapy than subjects receiving either Ibuprofen or a placebo, although some subjects in each treatment group showed loss of attachment posttherapy. Since differences in treatment response might have been due to differences in the sub-gingival microbiota, the response to different therapies in subjects with different pretherapy subgmgival microbiotas was evaluated. 29 subjects exhibiting loss of attachment >2.5 mm at t or more sites during longitudinal monitoring were treated by modified Widman flap surgery at deep sites, subgingival scaling at all other sites and were randomly assigned one of the following agents: Augmentm. tetracycline. ibuprofen or a placebo. Treatment was completed within 30 days, during which time the subject took the assigned agent. Subgingival plaque samples were taken from the mesial surface of each tooth a! each visit and evaluated for their content of 14 subgingival species including P. gingivalis. P. nigrescens. P. intermedia and B. forsythus using DNA probes. 18 subjects with mean counts >10⁵ of 2 or more of these 4 species comprised the high test species group: 11 subjects with mean counts >10⁵ of 0 or 1 of the species, the low lest species group. Because this was a post-hoc analysis, the number of subjects in some of the treatment/test species groups was small. However, the 8 high test species subjects who received tetracycline showed the most attachment level gain (G.83±0.20 mm), while the 3 tetracycline-treated. low test species subjects showed minimal gain (0.05±0.28 mm) 10 months post-therapy. Low test species subjects receiving Augmentin (n=2) showed a mean gain in attachment of 0.67 (±0.59) mm. The mean % of sites showing either attachment gain or loss ≥2 mm was computed for each treatment/test species group. High test species subjects receiving tetracycline exhibited the best ratio of gaining to losing sites (16.2), followed by low test species subjects receiving Augmentin (14.1). Periodontal pockets <7 mm pre-therapy in low test species subjects treated with Augmentin and high test species subjects treated with tetracycline showed attachment gain more frequently than attachment loss. The greatest proportion of gaining sites was seen at pockets >6 mm, particularly in subjects receiving adjunctive tetracycline. Overall, the data indicated that a gain in mean attachment level post-therapy was significantly associated (p<0.001) with an increase in C. ochraceu accompanied by a decrease in B. forsythus, P. gingivalis. P. intermedia and P. nigrescens. The 4 test species were decreased more in subjects receiving tetracycline. In contrast, Augmentin appeared to be effective in decreasing the % sites colonized by A. actinomycetemcomitans and in increasing the proportion of sites colonized by C. ochracea. Knowledge of the baseline microbiota should improve the choice of an appropriate adjunctive antibiotic for periodontal therapy.     

Clinical and microbiological features of subjects with adult periodontitis who responded poorly to scaling and root planing

Abstract In a previous report, it was shown that scaling and root planing (SRP) decreased mean pocket depth and attachment level in subjects with adult periodontitis, as well as the levels and prevalence of Bacteroides forsythus, Porphyromonas gingivalis and Treponema denticola. However, a subset of subjects in that study exhibited mean loss of attachment following SRP. The purpose of the present investigation was to seek clinical and microbiological differences between subjects who responded well or poorly to SRP. 57 subjects with adult periodontitis were treated by full-mouth SRP under local anaesthetic. Clinical assessments of plaque, redness, suppuration, BOP, pocket depth and attachment level were made at 6 sites per tooth prior to and 3 months post-SRP. Attachment level measurements were repeated at each visit and differences in means between visits used to assess change. 18 subjects showed mean attachment loss 3 months post-SRP (poor response group), while 39 showed mean attachment level gain (good response group). The prevalence and levels of 40 subgingival taxa in subgingival plaque samples from the mesiobuccal site of each tooth (maximum 28 sites) in each subject prior to and 3 months post-SRP were assessed using checkerboard DNA-DNA hybridization. The prevalence of each species was computed for each subject and averaged across subjects in the 2 treatment-response groups at each visit. Differences between groups were sought using the Mann-Whitney test. There were no statistically significant differences between the 2 response groups in any clinical parameter prior to therapy. Subjects in the good response group showed more attachment level gain at sites with baseline pocket depths of < 4 mm, 4–6 and > 6 mm than poor response subjects. Of 40 species evaluated. A. naeslundii genospecies 2 (A. viscosus), T. denticola, C. gracilis and C. rectus were significantly higher and more prevalent pre-therapy in the good response subjects. Mean attachment level change post SRP could be predicted using multiple linear regression with A. naeslundii genospecies 2 (A. viscosus) and T. denticola as the predictor variables (r²=0.373, p < 0.00001). Sites that gained ≥ 2 mm of attachment post therapy showed a significant decrease in the counts of P. gingivalis (7.5±3.5 to 0.2±0.2×10⁵), T. denticola (8.2±3.5 to 1.8±1.1×10⁵) and B. forsythus (11.1 ± 5.7 to 0.3±0.2×10⁵). The data of the present investigation indicate that SRP is most effective in subjects and sites with high levels of the subgingival species that this therapy affects.     

Levels of Selenomonas species in generalized aggressive periodontitis

Gonçalves LFH, Fermiano D, Feres M, Figueiredo LC, Teles FRP, Mayer MPA, Faveri M. Levels of Selenomonas species in generalized aggressive periodontitis. J Periodont Res 2012; 47: 711–718. © 2012 John Wiley & Sons A/S Background and Objective: To compare the levels of Selenomonas sputigena and uncultivated/unrecognized Selenomonas species in subgingival biofilms from periodontally healthy subjects and from subjects with generalized aggressive periodontitis. Material and Methods: Fifteen periodontally healthy subjects and 15 subjects with generalized aggressive periodontitis were recruited and their clinical periodontal parameters were evaluated. Nine subgingival plaque samples were collected from each subject and all were individually analyzed for the levels of 10 bacterial taxa, including cultured and uncultivated/unrecognized microorganisms, using the RNA‐oligonucleotide quantification technique. Between‐group differences in the levels of the test taxa were determined using the Mann–Whitney U‐test. Results: Subjects with generalized aggressive periodontitis showed significantly higher mean counts of Porphyromonas gingivalis, S. sputigena and the Mitsuokella sp. Human Oral Taxon (HOT) 131 (previously described as Selenomonas sp. oral clone CS002), while higher mean counts of Actinomyces gerencseriae and Streptococcus sanguinis were found in periodontally healthy subjects (p < 0.01). Selenomonas sp. HOT 146 was only detected in the generalized aggressive periodontitis group. In the generalized aggressive periodontitis group, the levels of P. gingivalis and S. sputigena were higher in deep sites (probing depth ≥ 5 mm) than in shallow sites (probing depth ≤ 3 mm) (p < 0.01). Furthermore, in subjects with generalized aggressive periodontitis, sites with probing depth of ≤ 3 mm harbored higher levels of these two species than sites with the same probing depth in periodontally healthy subjects. There were positive correlations between probing depth and the levels of P. gingivalis (r = 0.77; p < 0.01), S. sputigena (r = 0.60; p < 0.01) and Selenomonas dianae (previously described as Selenomonas sp. oral clone EW076) (r = 0.42, p < 0.05). Conclusion: S. sputigena and Mitsuokella sp. HOT 131 may be associated with the pathogenesis of generalized aggressive periodontitis, and their role in the onset and progression of this infection should be investigated further.     

Quantitative analysis of microbiota in saliva, supragingival, and subgingival plaque of Chinese adults with chronic periodontitis

Objective

The aim of this study was to determine the profiles of periodontopathogenic bacteria in a Chinese population using quantitative real-time polymerase chain reaction (qRT-PCR).

Materials and methods

Twenty-four periodontally healthy Chinese subjects and 60 patients with chronic periodontitis (CP) were enrolled in this cross-sectional study. qRT-PCR was used to quantify Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis, and Prevotella intermedia as well as total bacterial counts from 252 samples collected from the saliva, supragingival plaque, and subgingival plaque of all 84 subjects.

Results

The detection frequency of A. actinomycetemcomitans was less than 50%. F. nucleatum was detected in all subjects and CP patients had higher bacterial loads than healthy subjects. The median proportion of F. nucleatum was significantly higher in subgingival plaque than in supragingival plaque and saliva. P. gingivalis and P. intermedia had higher detection frequencies and bacterial loads in CP patients than in healthy subjects. The median proportion of P. gingivalis was significantly different among the three intraoral locations in the CP group and its proportion in subgingival plaque was 9.01%. Moreover, strong positive Spearman’s correlations were found in A. actinomycetemcomitans, P. gingivalis, and P. intermedia counts across the three intraoral locations.

Conclusion

The presence and bacteria loads of these four bacteria in this Chinese population are similar to those from other populations.

Clinical relevance

Examination of bacterial detection frequency and loads in Chinese adults may assist microbial studies of periodontal disease and will shed light on periodontal disease diagnosis and treatment using antibiotics in the Chinese population.     

Subgingival microbiota in healthy, well-maintained elder and periodontitis subjects

Abstract. This investigation compared the site prevalence of 40 subgingival species in 30 periodontally healthy (mean age 36±9 years). 35 elders with a well-maintained periodontium (mean age 77±5) and 138 adult periodontitis subjects (mean age 46± 11). Subgingival plaque samples were taken from the mesial aspect of each tooth (up to 28 samples) in the 203 subjects at baseline. The presence and levels of 40 subgingival taxa were determined in 5003 plaque samples using whole genomic DNA probes and checkerboard DNA-DNA hybridization. Clinical assessments including dichotomous measures of gingival redness, bleeding on probing, plaque accumulation and suppuration, as well as duplicate measures of pocket depth and attachment level, were made at 6 sites per tooth. The % of sites colonized by each species (prevalence) was computed for each subject. Differences in prevalence and levels among groups were sought using the Kruskal-Wallis test. Commonly detected species, such as Actinomyces naeslundii genospecies 2, Streptococcus sanguis and Streptococcus oralis did not differ significantly among subject groups. After adjusting for multiple comparisons, 4 species were significantly elevated and at greater prevalence in the periodontitis group. Mean % of sites (±SEM) colonized by Bacteroides forsythus was 10±3, 12±2 and 40±2 (p<0.001) for healthy, elder and periodontitis groups respectively. The odds ratio was 14.4:1 that a subject had periodontitis when B. forsythus was detected at ≥5% of sampled sites. Mean prevalence for Porphyromonas gingivalis in healthy, elder and periodontitis subjects was 4±2, 5±2 and 23±2 respectively (p<0.001); for Treponema denticola 12±4, 10±3 and 30±2 (p<0.001) and for Selenomonas noxia 6±2, 7±2 and 19±2 (p<0.01). Similar differences among subject groups were observed when only sites with PD 0-4 mm were analyzed. The data suggest an etiologic role for B. forsythus, P. gingivalis, T. denticola and S. noxia in adult periodontitis.     

Composition of supra- and subgingival biofilm of subjects with healthy and diseased implants

Objectives: The purpose of this study was to compare the microbial composition of supra‐ and subgingival biofilm in subjects with and without peri‐implantitis. Material and methods: Forty‐four subjects (mean age 48.9 ± 13.51 years) with at least one implant restored and functional for at least 2 years were assigned to two groups: a peri‐implantitis group (n=22), consisting of subjects presenting peri‐implant sites with radiographic defects >3 mm, bleeding on probing and/or suppuration; and a control group (n=22), consisting of subjects with healthy implants. The clinical parameters evaluated were plaque index, gingival bleeding, bleeding on probing, suppuration, probing depth and clinical attachment level. Supra‐ and subgingival biofilm samples were taken from the deepest sites of each implant and analyzed for the presence of 36 microorganisms by checkerboard DNA–DNA hybridization. Results: Higher mean counts of Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia were observed in the peri‐implantitis group, both supra‐ and subgingivally (P<0.05). The proportions of the pathogens from the red complex were elevated, while host‐compatible beneficial microbial complexes were reduced in diseased compared with healthy implants. The microbiological profiles of supra‐ and subgingival environments did not differ substantially within each group. Conclusion: Marked differences were observed in the composition of supra‐ and subgingival biofilm between healthy and diseased implants. The microbiota associated with peri‐implantitis was comprised of more periodontal pathogenic bacterial species, including the supragingival biofilm.     

Utility of 5 major putative periodontal pathogens and selected clinical parameters to predict periodontal breakdown in patients on maintenance care

Abstract The predictive utility of 5 major putative periodontopathic microbial species, “superinfecting” organisms, and several clinical periodontal parameters were assessed relative to periodontitis recurrence over a 12-month period in 78 treated adult patients participating in a 3-month maintenance care program. At baseline, pooled subgingival microbial samples were collected from each patient, and whole-mouth evaluations of probing depth, relative periodontal attachment level, furcation involvement, and indices of plaque and gingival inflammation were carried out. 67 (85.9%) subjects were culture-positive at baseline for presence of either Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia. Campylobacter rectus or Peptostreptococcus micros, with 48 (61.5%) subjects yielding one or more of these species at or above designated threshold proportions of ≥0.01% for A. actinomycetemcomitans, ≥0.1% for P. gmgivalis, ≥2.5% for P. intermedia, ≥2.0% for C. rectus, and ≥3.0% for P. micros. Subgingival yeasts were recovered from 12 subjects, staphylococci from 7, and enteric rods/pseudomonads from 6; however, no subjects revealed 21.0% baseline proportions of these “superinfecting” organisms in subgingival specimens. Periodontitis recurrence in subjects was defined as any periodontal site exhibiting either a probing depth increase of 2:3 mm from baseline, or a probing depth increase of 22 mm from baseline together with a loss in relative periodontal attachment of 22 mm from baseline. 15 (19.2%) study subjects showed periodontitis recurrence within 6 months of baseline, and 25 (32.1%) within 12 months. The mere baseline presence of the 5 major test species and “superinfecting” organisms were not significant predictors of periodontilis recurrence over 12 months. However, a 2.5 relative risk for periodontitis recurrence over 12 months was found for subjects yielding one or more of the 5 major test species at or above the designated baseline threshold proportions (p=0.022. Mantel-Haenszel %2 test). The positive predictive value for periodontitis recurrence of a microbiologic analysis encompassing the 5 major test species at or above the designated threshold proportions improved with increasing time from baseline, up to approximately 42% at 12 months. Baseline variables jointly providing in multiple regression analysis the best predictive capability for periodontitis recurrence in subjects over a 12-month period were recovery of one or more of the 5 major test species at or above designated threshold proportions, the proportion of sites per subject with 25 mm probing depth, and the mean whole-mouth probing depth. These findings indicate that one or more of 5 major putative periodontal pathogens in elevated subgingival proportions together with increased probing depth predispose adults on maintenance care to recurrent periodontitis.