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Notes: Background, aims: Polymorphisms in the cluster of IL-1 genes have been significantly associated with the severity of adult periodontitis. The purpose of this study was to compare microbiological parameters in IL-1 genotype negative and positive adult subjects with a range of periodontitis severities.Method: The study included 108 subjects in good general health. Clinical parameters were recorded at 6 sites/tooth excluding 3rd molars and included: plaque accumulation, gingival erythema, bleeding on probing, suppuration, pocket depth and attachment level. Subgingival plaque samples were collected from the mesiobuccal surface of up to 28 teeth in each subject (mean 25.3) providing a total of 2736 samples. The levels of 40 subgingival taxa were determined in each sample using checkerboard DNA-DNA hybridization. Fingerstick blood samples were collected for IL-1A (+4845) and IL-1B (+3954) genotyping using PCR-based methods.Results: The proportion of IL-1 genotype positive subjects that exhibited mean counts of specific subgingival species above selected thresholds was significantly higher than the proportion of genotype negative subjects. Prominent among species that were detected at higher levels in genotype positive subjects were members of the “red” and “orange” complexes and included: Bacteroides forsythus, Treponema denticola, the Fusobacterium nucleatum subspecies, Fusobacterium periodonticum, Campylobacter gracilis, Campylobacter showae and Streptococcus constellatus. Streptococcus intermedius, Streptococcus gordonii and 3 Capnocytophaga species were also detected more frequently at high numbers in genotype positive subjects. Significantly higher mean counts of B. forsythus, Porphyromonas gingivalis, T. denticola, the F. nucleatum subspecies, F. periodonticum, Campylobacter rectus, C. showae, Eubacterium nodatum, S. constellatus, S. gordonii, and S. intermedius were detected at periodontal pockets 〉6 mm in subjects who were genotype positive when compared with genotype negative subjects. The increase was due to increased numbers of cells of these species rather than a major shift in proportion.Conclusion: The data suggest that genotype positive subjects more frequently had higher levels of “red” and “orange” complex species that are known to be strongly associated with measures of periodontal inflammation.

Notes: Previously, we reported that SRP resulted in a decrease inmean pocket depth and attachment level and reduced prevalence and levels of Bacteroides forsythus, Porphyromonas gingivalis, and Treponema denticola at 3 and 6 months post-SRP in 57 subjects with adult periodontitis. 32 of the 57 subjects were monitored at 9 and 12 months. Thus, the purpose of the present investigation was to evaluate the microbial and clinical effects of SRP in 32 (mean age 48±11) subjects over a 12-month period.Method: Clinical assessments of plaque, gingival redness, suppuration, bleeding on probing, pocket depth and attachment level were made prior to SRP and at 3, 6, 9, and 12 months post-therapy. Subgingival plaque samples were taken at each visit and analyzed using the checkerboard DNA-DNA hybridization technique for the presence and levels of 40 subgingival species. Each subject also received maintenance scaling at each of the subsequent monitoring visits. Differences in clinical parameters and prevalence and levels of bacterial species were analyzed pre- and post-therapy using the Wilcoxon signed ranks test. The Quade test for related samples was used for analysis of multiple visits.Results: Mean pocket depth (mm±SEM) decreased from 3.2±0.3 at baseline to 2.9±0.3 at 12 months (p〈0.01). Mean attachment level showed significant reduction at 6 months, but did not diminish further. Bleeding on probing and plaque were significantly reduced at 12 months (p〈0.001, p〈0.05, respectively). P. gingivalis, B. forsythus and T. denticola decreased in prevalence and levels up to the 6-month visit and remained at these lower levels at 9 and 12 months. Significant increases in levels and prevalence were noted at 12 months for Actinomyces naeslundii genospecies 2, Actinomyces odontolyticus, Fusobacterium nucleatum ss polymorphum, Streptococcus mitis, Capnocytophaga sp, and Veillonella parvula.Conclusions: The data suggest that the maintenance phase of therapy may be essential in consolidating clinical and microbiological improvements achievedas a result of initial therapy.

Notes: Abstract. The purpose of this investigation was to compare the levels of serum IgG2, the frequency of detection of Gm(23)-negative allotype and frequency of detection of FcγRIIa and FcγRIIIb receptor haplotypes in 32 refractory, 54 successfully treated and 27 periodontally healthy individuals. Refractory subjects showed mean full mouth attachment loss and/or 〉 3 sites with attachment loss 〉 2.5 mm within 1 year after both scaling and root planing, and surgery plus systemically administered tetracycline. Successfully treated subjects showed mean attachment level gain and no sites with attachment loss 〉 2.5 mm 1 year post-therapy. Periodontally healthy subjects exhibited no pocket depth or attachment level 〉 3 mm. and no evidence of progressing disease during 1 year of monitoring. Blood was obtained from each subject al baseline. Serum IgG2 and Gm(23) allotype were determined using radial immunodiffusion. DNA was extracted from whole blood and the FcγR genotypes determined using PCR and allele specific oligonucleotide probes. Significance of differences among clinical groups were sought using the Kruskal-Wallis or chi-square tests. Associations between 2 or more variables were tested using regression analysis. Refractory subjects exhibited higher mean attachment loss and pocket depth than successfully treated or periodontally healthy subjects. Smoking status did not differ significantly among groups. No significant differences in serum IgG2 levels and frequency of detection of Gm(23)-negative allotype were observed among the clinical groups. Serum IgG2 level was positively associated with the number of serum antibody responses to subgingival species (r-0.51.P〈0.001). Subjects with the Gm(23)- negative allotype exhibited lower mean levels of serum lgG2 (3.06±0.3 versus 3.9±0.2. p〈0.01) and mean number of serum antibodies to subgingival species (17.7±1.7 versus 23.3±1.4, p〈0.05) than allotype positive individuals. No significant differences in FcγR haplotype distribution were observed among the 3 clinical groups. Associations of serum IgG2 level. Gm(23) allotype. FcγRIIa and FcγRIIIb receptor haplotypes and smoking status were weakly related or not related to clinical status. This lack of relationship may have been due to a reality of no relationship, or the inadvertent pooling of subjects where these factors were of primary importance with subjects in whom these factors played a less important role.

Notes: Abstract. The purpose of the present investigation was to use baseline clinical and laboratory parameters to distinguish subjects refractory to conventional periodontal therapy. Baseline clinical, microbial and host parameters were compared in 61 successfully-treated and 27 refractory subjects. Refractory subjects showed mean full-mouth attachment level (AL) loss and/or 〉3 sites with new AL loss 〉2.5 mm within 1 year after both scaling and root planing and surgery with systemic tetracycline. Successfully-treated subjects showed mean AL gain and no sites with new ALloss〉2.5mmafter either regimen. Gingival redness, bleeding on probing, suppuration, supragingival plaque accumulation, pocket depth and AL were measured at 6 sites per tooth in each subject. The levels of 40 subgingival taxa were determined in subgingival plaque samples from up to 28 sites in each subject using checkerboard DNA-DNA hybridization. Serum antibody (Ab) to 85 subgingival species was determined using checkerboard immunoblotting. Levels of serum IgG2 and Gm23 allotype were measured using radial immunodiffusion; FcγRIIa and FcγRIIIb receptor haplotypes were determined using PCR and allele specific oligonucleotide probes. Odds ratios of a subject being refractory were determined by comparing measured parameters in the 2 subject groups using univariate and multivariate techniques. 17 of 151 clinical, microbial and immunological variableswere significant using χ2 analysis after adjusting for multiple comparisons. For example, the odds ratios of a subject being refractory were 12.2, 5.4 and 6.9 if the subject had Ab 〉50 μg/ml to 〉9 species; S. constellatus counts 〉2.4% of the total DNA probe count or 〉2.1% of sites with AL 〉6 mm. The 17 significant predictor variables were used in logistic regression and discriminant analyses. Similar variables were selected using both analyses including the number of serum Ab to subgingival species 〉50 mg/ml, % S. constellatus in plaque samples and % sites with attachment loss 〉6 mm. In the logistic regression analysis model, the odds ratios associated with 〉9 species exhibiting 〉Ab 50 μg/ml, 〉2.1% of sites with AL 〉6 mm and〉2.4% S. constellatus in plaque were 8.7, 6.8 and 2.4, respectively, after adjusting for other variables in the model. Discriminant analysis using these variables provided sensitivity, specificity, positive and negative predictive values of 0.66, 0.92, 0.80 and 0.85 respectively. Refractory periodontitis subjects could be distinguished using a subset of clinical, microbiological and immunological parameters.

Notes: 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.

Notes: Abstract. The purpose of this investigation was lo compare the clinical parameters and the site prevalence and levels of 40 subgingival species in successfully treated and refractory periodontitis subjects. 94 subjects received scaling and root planing and if needed, periodontal surgery and systemically administered tetracycline. 28 refractory subjects showed mean full mouth attachment loss and/or 〉3 sites showing attachment loss 〉2.5 mm within 1 year post-therapy. 66 successfully treated subjects showed mean attachment level gain and no sites with attachment loss 〉2.5 mm. Baseline subgingival plaque samples were taken from the mesial aspect of each tooth and the presence and levels of 40 subgingival taxa were determined using whole genomic DNA probes and checkerboard DNA-DNA hybridization. The mean levels and % of sites colonized by each species (prevalence) was computed for each subject and differences between groups sought using the Mann-Whitney test. Most of the 40 species tested, including Actinobacillus actinomycetemcomitans. Porphyromonas gingivalis, Treponema denticola and Bacteroides forsythus, were equally or less prevalent in the refraclory group. Prevotella nigrescens was significantly more prevalent in successfully treated subjects, while refractory subjects harbored a larger proportion of Streptococcus species, particularly Streptococcus constellatus. The odds of a subject being refractory was 8.6 (p〈0.001) if S. constellatus constituted ≤3.5% of the total DNA probe count. Since few microbiological differences existed between treatment outcome groups using DNA probes to known species, the predominant cultivable microbiota of 33 subgingival samples from 14 refractory subjects was examined, 85% of the 1649 isolates were identified using probes to 69 recognized subgingival species. The remaining unidentified strains were classified by analyzing 16S rRNA gene sequences. Many sequenced isolates were of taxa not considered a common part of the oral microbiota such as Acinetobacter baumanni, Gemella haemolysans, Enterococcus faecalts, Staphyhcoccus warneri, Pseudomonas aeruginosa and novel species in the genera Bartonella, Ralstonia, Neisseria, Eubacterium, Rothia, Gordona, Gemella, Corynebacterium, Leptotrichia, and Actinomyces. Refractory subjects constituted a heterogeneous group based on their subgingival microbiota. As a group, they did not harbor more of the “classic” periodontopathogens, although elevated proportions of S. constellatus were found.

Notes: The purpose of the present investigation was to examine the effect of SRP on clinical and microbiological parameters in 57 subjects with adult periodontitis (mean age 47± 11 years). Subjects were monitored clinically and micro-biologically prior to and 3, 6 and 9 months after full-mouth SRP under local anaesthesia. Clinical assessments of plaque, redness, suppuration, BOP, pocket depth and attachment level were made at 6 sites per tooth. The means of duplicate attachment level measurements taken at each visit were used to assess change between visits. Clinical data were averaged within each subject and then averaged across subjects for each visit. Subgingival piaque samples were taken from the mesial aspect of each tooth and the presence and levels of 40 subgingival taxa were determined using whole genomic DNA probes and checkerboard DNA-DNA hybridization. The mean levels and % of sites colonized by each species (prevalence) was computed for each subject at each visit. Differences in clinical and microbiological parameters before and after SRP were sought using the Wilcoxon signed ranks test or the Quade test for more than 2 visits. Overall, there was a mean gain in attachment level of 0.11±0.23 mm (range –0.53 to 0.64 mm) 3 months post-therapy. There was a significant decrease in the % of sites exhibiting gingival redness (68 to 57%) and BOP (58 to 52%) as well as a mean (±SEM) pocket depth (3.3±0.06 to 3.1 ±0.05 mm). Sites with pre-therapy pocket depths of 〈4 mm showed a non-significant increase in pocket depth and attachment level. 4–6 mm pockets showed a significant decrease in pocket depth and a non-significant gain in attachment post-therapy, while 6 mm pockets showed a significant decrease in pocket depth and attachment level measurements post-therapy. Significant clinical improvements were seen in subjects who had never smoked or were past smokers but not in current smokers. Mean prevalences and levels of P. gangivalis, T. denticola and B. forsythus were significantly reduced after SRP. while A. viscosus showed a significant increase in mean levels. The mean decrease in prevalence of P. gingivalis was similar at all pocket depth categories, while B. forsythus decreased more at shallow and intermediate pockets and A. viscosus increased most at deep sites, P. gingivalis, B. forsythus and T. denticola were equally prevalent among current, past and never smokers pre-therapy, decreased significantly post-SRP in never and past smokers but increased in current smokers. Clinical improvement post-SRP was accompanied by a modest change in the subgingival microbiota, primarily a reduction in P. gingivalis, B. forsythus and T. denticola, suggesting potential targets for therapy and indicating that radical alterations in the subgingival microbiota may not be necessary or desirable in many patients.

Notes: Fifty-one subjects (16–61 years old) with evidence of prior destructive periodontal disease were monitored clinically and immunologically at bi-monthly intervals for up to 5 yr. Periodontal disease activity, determined as new attachment loss, was detected in 33 of these subjects. Only 4 of 51 subjects failed to show an elevated serum antibody level to any of the 18 subgingival species tested. The antibody level threshold established for periodontally healthy subjects was exceeded most often in diseased subjects with serum antibody to Actinobacillus sp., P. gingivalis, E. corrodens, C. concisus, F. nucleatum and P. intermedia in that order. In general, most serum antibody levels to subgingival species remained relatively consistent for periods as long as 5 yr. However, major increases and decreases in antibody could be detected to at most one or two species in individual subjects. In addition, prolonged, steady increases and decreases in antibody to specific species could be detected in certain subjects. These findings suggest that major changes occurring in serum antibody may reflect fluctuations in the nature of the infection. Differences were observed in the antibody level to specific species when subjects were divided into subsets on the basis of clinical criteria. These included high levels of antibody to A. actinomycetemcomitans Y4 in LJP and RPP subjects and to A. actinomycetemcomitans 29523 in LJP and GJP subjects.

Notes: The ratio of helper (T4+) to suppressor (T8+) T cells was determined in a population of periodontitis patients and in normal subjects. Although patients as a group were found to have the same T4/T8 ratio as normal individuals, that subgroup of patients previously identified as T cell low responders to oral microorganisms exhibited a relative increase in circulating suppressor T cells. Conversely, unusually low T4/T8 ratios were predictive of low level T cell proliferative responses generated against 7/12 oral microorganisms tested. Patients with low T4/T8 ratios had significantly more redness and bleeding on probing than did those with high T4/T8 ratios, but did not differ with respect to plaque, pocket depth, attachment loss, or episodes of disease activity. These results extend previous observations concerning the relationship between the in vitro T cell response to oral microorganisms and gingival inflammation.