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Recent studies of the dental plaque bacteria associated with the various forms of early-onset periodontitis confirm the importance of target periodontal pathogens such as Actinobacillus actinomycetemcomitans, Bacteroides forsythus, Prevotella intermedia, and Porphyromonas gingivalis in these diseases. A. actinomycetemcomitans strains exhibit a wide range of variability in leukotoxin production. By virtue of a unique promoter for the leukotoxin (ltx) operon, highly leukotoxic A. actinomycetemcomitans strains (e.g., JP2) express 10- to 20-times greater levels of leukotoxin than minimally toxic strains (e.g., 652). In dot blot hybridization and polymerase chain reaction (PCR) assays, the distribution of leukotoxic A. actinomycetemcomitans was examined among 165 fresh isolates and strains from our culture collection obtained from 91 human patients and non-human primates. Highly leukotoxic A. actinomycetemcomitans strains were found in 22% of the subjects and represented 28% of the isolates examined. This is a much higher prevalence than reported in a similar survey of A. actinomycetemcomitans strains from Northern Europe. Patients harboring the highly leukotoxic strains were much younger (mean age 12.7 years) than those harboring minimally toxic A. actinomycetemcomitans (mean age 25.5 years). In addition, patients with localized juvenile periodontitis were shown to have a substantially higher prevalence of highly leukotoxic strains than healthy individuals or those with adult periodontitis. Fifty-seven percent of the localized juvenile periodontitis patients harbored these strains and 64% of the isolates obtained from these patients were highly toxic A. actinomycetemcomitans. No highly toxic strains were identified from healthy individuals or from patients with adult periodontitis. The polymerase chain reaction assay could readily identify and distinguish the ltx promoters from highly toxic and minimally toxic A. actinomycetemcomitans in whole plaque samples. These data point to the importance of specific A. actinomycetemcomitans strains, as characterized by their expression of high levels of leukotoxin, in the pathogenesis of certain types of early-onset periodontitis and, possibly, other forms of rapidly progressing periodontitis. J Periodontol 1996;67:282-290.

Periodontal regeneration-treatment that results in new alveolar bone, cementum, and a functional periodontal ligament-is successful in class II furcation defects. This article examines one aspect of periodontal regeneration-alveolar bone growth in furcation defects-in trying to answer the question, Can bone lost from furcations be regenerated? The best evidence for bone growth is histology but there is limited histologic evidence for bone growth in human furcation defects. There is more evidence from intraoperative measurements for hard tissue growth in treated furcation defects, but the nature of the hard tissue needs to be determined histologically.

Aim: Oral malodor (halitosis) is a widespread condition caused by oral bacteria, particularly sulfur compound-producing species. This study assessed the effect of a triclosan/copolymer-containing dentifrice and a novel toothbrush with attached tongue cleaner on oral malodor and on the bacteria colonizing the dorsal surface of the tongue. Materials and Methods: 14 adult subjects with oral malodor defined as organoleptic scores ≥ 3 (scale 0 - 5) and mouth air sulfur levels ≥ 250 ppb participated in this study. Subjects were examined at baseline and after 28 days use of the triclosan dentifrice and toothbrush/tongue cleaner for: 1) organoleptic assessment; 2) mouth air sulfur levels; 3) tongue coating; and, 4) dorsal tongue surface microorganisms. Total bacterial numbers were assayed by microscopy. Dot-blot hybridization was used to assess a panel of 20 oral bacteria. Results: After 28 days, all subjects had significantly reduced organoleptic scores and mouth air sulfur levels compared to baseline (p 70% reduction in microbial numbers (p Enterococcus faecalis (p Peptostreptococcus micros (p Prevotella melaninogenica (p Porphyromonas gingivalis (p Solobacterium moorei (p

Aim: To test the hypothesis that antimicrobial agents can be incorporated into bis-acryl resin and that the material will inhibit bacterial growth in vitro. Materials and Methods: 0.5%, 1% and 2% triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol) and 0.05% 0.01% and 0.15% cetylpyridinium chloride were incorporated into bis-acryl resins and molded into 1 mm × 10 mm discs. The discs were placed on bacterial culture media inoculated with Aggregatibacter actinomycetemcomitans strain Y4, Porphyromonas gingivalis strain SUNYaB A7A1-28 or Streptococcus gordonii strain 10558, incubated and examined for growth inhibition. Results: Triclosan-containing bisacryl resin discs produced dose-dependent zones of growth inhibition for A. actinomycetemcomitans but not S. gordonii or P. gingivalis. Cetylpyridinium chloride-containing discs produced dose-dependent zones of growth inhibition for Porphyromonas gingivalis and Streptococcus gordonii but not A. actinomycetemcomitans. Conclusion: Triclosan and cetylpyridinium chloride can be incorporated into bis-acryl resin and can inhibit the growth of plaque bacteria in a dose dependent manner. Bis-acryl resin containing antimicrobial agents may inhibit in vivo plaque accumulation and gingival inflammation.

This study evaluated the antimicrobial activity of two commercially available 0·05% cetylpyridinium chloride (CPC) mouthrinses with or without alcohol and examined its antimicrobial activity on oral bacterial species including fresh clinical isolates compared to a chlorhexidine mouthrinse and a control fluoride mouthrinse without CPC. Two different approaches were used to evaluate antimicrobial activity. First, the minimum inhibitory concentration (MIC) was determined for each mouthrinse against a panel of 25 micro-organisms including species associated with dental caries, gingivitis and periodontitis. Second, supragingival dental plaque obtained from 15 adults was incubated with the four mouthrinses to evaluate antimicrobial activity on micro-organisms in oral biofilms. Both CPC mouthrinses exhibited lower MIC's, that is, greater antimicrobial activity, against oral Gram-negative bacteria especially periodontal pathogens and species implicated in halitosis such as Aggregatibacter actinomycemcomitans, Campylobacter rectus, Eikenella corrodens, Porphyromonas gingivalis, Prevotella intermedia and Solobacterium moorei than the control mouthrinse. Ex-vivo tests on supragingival plaque micro-organisms demonstrated significantly greater antimicrobial activity by the CPC mouthrinses (>90% killing, P 98% killing, P

To cite this article: Int J Dent Hygiene9, 2011; 136–142 DOI: 10.1111/j.1601-5037.2010.00465.x Sreenivasan PK, Haraszthy VI, Zambon JJ.The effect of a microbead dentifrice on microbial load in oral microenvironments. Abstract: Objectives: The human oral cavity contains several microenvironments or ecologic niches. While mechanical plaque control is well known to reduce the number of supragingival dental plaque bacteria, there is little data on antimicrobial effects in other oral ecologic niches. The present study examined the effects of mechanical plaque control using a microbead dentifrice on bacteria colonizing oral ecologic niches. Methods: Twenty-two adults (aged 18–70 years) including nine generalized moderate chronic periodontitis subjects and 13 periodontally healthy subjects having average gingival indices ≥1 and plaque indices ≥1.5 completed a 1 week washout phase and refrained from oral hygiene the morning of baseline sample collection. Microbial samples from supragingival dental plaque, buccal mucosa, dorsal surface of the tongue and whole mixed saliva were obtained. Subjects brushed with a microbead dentifrice and, after 10 min, sampling was repeated. The number of anaerobic bacteria was determined by culture on non-selective media and transformed to log10 for statistical analyses. Results: Mechanical plaque control using the microbead dentifrice resulted in statistically significant reductions in bacterial numbers in each ecologic niche (P

This study compared a rapid, colorimetric DNA probe assay designed to be performed in a dental office within 40 min, with anaerobic culture and indirect immunofluorescence microscopy (IFM) for detection of Bacteroides forsythus and Porphyromonas gingivalis in subgingival plaque samples. The DNA probe assay used the Periodontal Microbial Identification Test (Saigene Corporation, Bothell, Washington, USA). B. forsythus was detected in 46 (52%), 49 (55%) and 39 (44%) of the samples by DNA probe, culture (at levels > or = 10(5)) and IFM, respectively. P. gingivalis was detected in 24 (27%), 18 (20%) and 29 (33%) of the samples by DNA probe, culture (at levels > or = 10(5)) and IFM, respectively. Results from the DNA probe assay were compared to culture. Culture negative, probe positive samples were re-evaluated by IFM, and IFM positive samples were considered positive in "resolved" data. Using resolved data. DNA probe detection sensitivity and specificity values for B. forsythus were 81% and 91% and for P. gingivalis were 80% and 95%, respectively. DNA probe test results were further compared with culture and IFM. For samples negative by both culture and IFM, probe specificity was 92% in 25 B. forsythus samples and 95% in 57 P. gingivalis samples. For samples positive by both reference methods, probe sensitivity was 82% in 27 B. forsythus samples and 73% in 15 P. gingivalis samples. B. forsythus was detected more frequently by culture compared with IFM; the reverse was observed for P. gingivalis. The rapid DNA probe assay for B. forsythus and P. gingivalis was comparable to cultivable and IF analyses.

Dentists and other health care professionals are familiar with the impact of tobacco on oral and general health. However, oral health care professionals do not often provide tobacco-cessation counseling to their patients, thus reflecting a significant disconnect between research and clinical practice. This report demonstrates the benefits of tobacco cessation in resolving oral lesions and improving overall periodontal and oral health.A 51-year-old white male presented to the University at Buffalo, School of Dental Medicine clinic requesting an oral and periodontal examination as part of a presurgical protocol prior to cardiac surgery. A review of the patient's history from a health questionnaire revealed that he was using smokeless tobacco every day. An oral examination revealed several white lesions (5 x 10 mm) on the maxillary right and left labial mucosa. The patient was provided with tobacco-cessation counseling as well as oral hygiene instructions and professional dental prophylaxis.An oral examination 2 weeks after tobacco cessation revealed complete resolution of the oral lesions and overall improvement of periodontal and oral health.Although the findings presented in this article are based only on a single case report, the improvement in the patient's oral health after cessation of tobacco use was dramatic and reinforces the belief that tobacco-cessation counseling should be a routine component of the standard of care for tobacco-using patients.

Background The authors examined the tongue bacteria associated with oral halitosis (bad breath originating from the oral cavity), focusing on noncultivable bacteria—bacteria that cannot be identified by bacterial culture techniques. Methods The authors took samples from the dorsal tongue surface of eight adult subjects with halitosis and five control subjects who did not have halitosis. They identified the bacteria in these samples by using both anaerobic culture and direct amplification of 16S ribosomal DNA, a method that can identify both cultivable and noncultivable microorganisms. They analyzed the resulting microbiological data using χ 2 and correlation coefficient tests. Results Clinical measures of halitosis were correlated highly with each other and with tongue coating scores. Of 4,088 isolates and phylotypes identified from the 13 subjects, 32 species including 13 noncultivable species were found only in subjects with halitosis. Solobacterium moorei was present in all subjects with halitosis but not in any control subjects. Conclusions Subjects with halitosis harbor some bacterial species on their dorsal tongue surfaces that are distinct from bacterial species found in control subjects. This finding is consistent with the hypothesis that halitosis has a microbial etiology. Clinical Implications Like other oral diseases with microbial etiology, halitosis may be amenable to specific and nonspecific antimicrobial therapy targeted toward the bacteria associated with it.

Periodontal regeneration-treatment that results in new alveolar bone, cementum, and a functional periodontal ligament-is successful in class II furcation defects. This article examines one aspect of periodontal regeneration-alveolar bone growth in furcation defects-in trying to answer the question, Can bone lost from furcations be regenerated? The best evidence for bone growth is histology but there is limited histologic evidence for bone growth in human furcation defects. There is more evidence from intraoperative measurements for hard tissue growth in treated furcation defects, but the nature of the hard tissue needs to be determined histologically.

Aims: To determine minimal inhibitory concentrations (MICs) and the percentage of nonsusceptible bacteria – those still cultivable above a threshold concentration – in human supragingival dental plaque and saliva for antiplaque/antimicrobial agents including triclosan (TCS) and trichlorocarbanilide (TCC), and a new potential antimicrobial, 2-t-butyl-5-(4-t-butylphenyl)-phenol (DTBBP). Methods and Results: Broth and agar dilution-based MIC tests were performed using 28 oral and nonoral bacterial strains representing 17 species. MICs for TCS were lowest and more than 100-fold lower than DTBBP (P

Made available in DSpace on 2019-09-12T16:56:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2005 Objectives: Previous studies suggest differences between geographically and racially distinct populations in the prevalence of periodontopathic bacteria as well as greater periodontal destruction associated with infection by highly leucotoxic Actinobacillus actinomycetemcomitans. The present study examined these hypotheses in Brazilians with aggressive or chronic periodontitis. Materials and Methods: Clinical, radiographical, and microbiological assessments were performed on 25 aggressive periodontitis and 178 chronic periodontitis patients including 71 males and 132 females, 15-69 years of age. Results: The prevalence of Porphyromonas gingivalis was similar to that of other South American populations. The prevalence of A. actinomycetemcomitans and its highly leucotoxic subgroup was higher in Brazilians. Highly leucotoxic A. actinomycetemcomitans was more prevalent in aggressive periodontitis (chi(2) = 527.83) and positively associated with deep pockets (46 mm, chi(2) = 18.26) and young age (< 29 years, chi(2) = 18.68). Greater mean attachment loss was found in subjects with highly leucotoxic A. actinomycetemcomitans than in subjects with minimally leucotoxic (p = 0.0029) or subjects not infected (p = 0.0001). Conclusion: These data support the hypothesis of differences between populations in the prevalence of periodontopathic bacteria and of greater attachment loss in sites infected with highly leucotoxic A. actinomycetemcomitans. Detection of highly leucotoxic A. actinomycetemcomitans in children and adolescents may be a useful marker for aggressive periodontitis. SUNY Buffalo, Sch Dent Med, Buffalo, NY 14214 USA; Universidade de Taubaté (Unitau), Sao Paulo, Brazil

In der vorliegenden Studie wurden von 62 Patienten (18 Frauen und 44 Manner) 93 Proben aus verschiedensten Gefasen und Gefasabschnitten wahrend der Gefasoperation entnommen und auf bakterielle 16S rDNS sowie—mittels spezifischen Oligonukleotidprimern—auf die mit Parodontitis assoziierten Keime P. gingivalis, P. intermedia, A. actinomycetemcomitans, C. rectus und B. forsythus untersucht. In 76,34% der 93 untersuchten Gefaswandpraparate waren Bakterien nachzuweisen, in 40,86% einer oder mehrere der parodontalpathogenen Erreger. Diese kamen so gut wie immer (mit einer Ausnahme) zusammen mit anderen Bakterien vor. C. pneumoniae fanden sich in 22,58% der Proben. Ihr Auftreten stand signifikant mit dem Vorkommen von parodontalpathogenen Keimen in Zusammenhang. Herpes-simplex- und Zytomegalieviren kamen in 24,73% bzw. 30,11% der Proben vor, ohne dass ein Zusammenhang mit Parodontalkeimen bestand. Diese Ergebnisse stehen im Einklang mit der Hypothese, dass Mikroorganismen, die mit Parodontitis assoziiert sind, bei der Atiologie und Pathogenese der Arteriosklerose eine wichtige Rolle spielen.

Introduction Recent studies suggest that chronic infections, including those associated with periodontitis, increase the risk for coronary vascular disease. We hypothesize that oral microorganisms including periodontal bacterial pathogens enter the blood stream during transient bacteremias where they may play a role in the development and progression of atherosclerosis. Materials and methods To test this hypothesis, 34 human specimens obtained during carotid endarterectomy or bypass procedures were examined by use of specific oligonucleotide primers for Porphyromonas gingivalis, Prevotella intermedia, Actinobacillus actinomycetemcomitans and Bacteroides forsythus in polymerase chain reaction (PCR) assays. Results Twenty (59%) of the 34 specimens tested positive for bacterial 16S rDNA. Subsequent hybridization of the bacterial 16S rDNA positive specimens with species-specific oligonucleotide probes revealed that 32.4% of the 34 atheromas tested positive for at least one of the target periodontal pathogens. Further analysis of the results in the bacterial positive group (n = 20) shows that 55% of the atheromas tested positive for at least one of the target periodontal pathogens. Conclusion These findings indicate that periodontal pathogens are present in atherosclerotic plaques, where they may play a role in the development and progression of atherosclerosis leading to coronary vascular disease and other clinical sequelae.

Periodontitis is a local inflammatory process mediating destruction of periodontal tissues triggered by bacterial insult. However, this disease is also characterized by systemic inflammatory host responses that may contribute, in part, to the recently reported higher risk for cardiovascular disease (CVD) among patients with periodontitis. Moderate elevation of C-reactive protein (CRP) has been found to be a predictor of increased risk for CVD. Elevated CRP levels in periodontal patients have been reported by several groups. In this study, we examined whether CRP plasma levels are increased in periodontitis and if there is a relation to severity of periodontal disease and to the periodontal microflora.CRP serum levels were assessed using radial immunodiffusion assay in 174 subjects, 59 with moderate mean clinical attachment loss (AL) (2.39+/-0.29 mm) and 50 with high AL (3.79+/-0.86 mm) as compared to 65 periodontally healthy controls (AL, 1.74+/-0.18 mm). Clinical attachment loss, probing depths, and percentage of periodontal pocket sitesor =5 mm were measured. The presence of periodontal pathogens Porphyromonas gingivalis (P.g.), Prevotella intermedia (P.i.), Campylobacter recta (C.r.), and Bacteroides forsythus (B.f.) in subgingival plaque samples was measured by immunofluorescence microscopy.Statistically significant increases in CRP levels were observed in subjects with periodontal disease when compared to healthy controls (P= 0.036). Subjects with high levels of mean clinical attachment loss had significantly higher mean CRP levels (4.06+/-5.55 mg/l) than controls (1.70+/-1.91 mg/l), P= 0.011. The CRP levels were adjusted for factors known to be associated with elevated CRP, including age, smoking, body mass index (BMI), triglycerides, and cholesterol. Age and BMI were found to be significant covariates. The reported range for CRP as a risk factor for CVD, peripheral vascular diseases, or stroke is 1.34 mg/l to 6.45 mg/l and the mean of this range is 3 mg/l. The percentage of subjects with elevated levels of CRPor = 3 mm was significantly higher in the high clinical AL group (38%; 95% Cl: 26.7%, 49.3%) when compared to the control group (16.9%; 95% CI: 9.25%, 24.5%), P= 0.011. The presence of periodontal pathogens P.g., P.i., C.r., and B.f. in subgingival samples was positively associated with elevated CRP levels (P= 0.029).The extent of increase in CRP levels in periodontitis patients depends on the severity of the disease after adjusting for age, smoking, body mass index, triglycerides, and cholesterol. Also, there are elevated levels of CRP associated with infection with subgingival organisms often associated with periodontal disease, including P.g., P.i., C.r., and B.f. Recent investigations emphasized the role of moderate elevated CRP plasma levels as a risk factor for CVD. The positive correlation between CRP and periodontal disease might be a possible underlying pathway in the association between periodontal disease and the observed higher risk for CVD in these patients.

Recent studies suggest that chronic infections including those associated with periodontitis increase the risk for coronary vascular disease (CVD) and stroke. We hypothesize that oral microorganisms including periodontal bacterial pathogens enter the blood stream during transient bacteremias where they may play a role in the development and progression of atherosclerosis leading to CVD.To test this hypothesis, 50 human specimens obtained during carotid endarterectomy were examined for the presence of Chlamydia pneumoniae, human cytomegalovirus, and bacterial 16S ribosomal RNA using specific oligonucleotide primers in polymerase chain reaction (PCR) assays. Approximately 100 ng of chromosomal DNA was extracted from each specimen and then amplified using standard conditions (30 cycles of 30 seconds at 95 degrees C, 30 seconds at 55 degrees C, and 30 seconds at 72 degrees C). Bacterial 16S rDNA was amplified using 2 synthetic oligonucleotide primers specific for eubacteria. The PCR product generated with the eubacterial primers was transferred to a charged nylon membrane and probed with digoxigenin-labeled synthetic oligonucleotides specific for Actinobacillus actinomycetemcomitans, Bacteroides forsythus, Porphyromonas gingivalis, and Prevotella intermedia.Eighty percent of the 50 endarterectomy specimens were positive in 1 or more of the PCR assays. Thirty-eight percent were positive for HCMV and 18% percent were positive for C. pneumoniae. PCR assays for bacterial 16S rDNA also indicated the presence of bacteria in 72% of the surgical specimens. Subsequent hybridization of the bacterial 16S rDNA positive specimens with species-specific oligonucleotide probes revealed that 44% of the 50 atheromas were positive for at least one of the target periodontal pathogens. Thirty percent of the surgical specimens were positive for B. forsythus, 26% were positive for P. gingivalis, 18% were positive for A. actinomycetemcomitans, and 14% were positive for P. intermedia. In the surgical specimens positive for periodontal pathogens, more than 1 species was most often detected. Thirteen (59%) of the 22 periodontal pathogen-positive surgical specimens were positive for 2 or more of the target species.Periodontal pathogens are present in atherosclerotic plaques where, like other infectious microorganisms such as C. pneumoniae, they may play a role in the development and progression of atherosclerosis leading to coronary vascular disease and other clinical sequelae.

A review of periodontal disease as a manifestation of HIV infection suggests a shift in emphasis over the past 5 years. Initially the focus was on newly described forms of periodontal disease (i.e., HIV-associated gingivitis or linear gingival erythema (LGE); HIV-associated periodontitis or necrotizing ulcerative periodontitis (NUP). While the clinical definition of LGE varies from study to study, an association between LGE and Candida infection has been described. Furthermore, the prevalence of NUP is quite low and this disorder is associated with severe immunosuppression. In contrast, the focus today is on the accelerated rate of chronic adult periodontitis occurring in seropositive patients. While the organisms that characterize adult periodontitis in seronegative individuals are present in subgingival plaque from seropositive individuals, reports suggest that atypical pathogens are also present (i.e., Mycoplasma salivarium, Enterobacter cloacae). Recent studies from our laboratory have identified a novel strain of Clostridium isolated from the subgingival plaque of injecting drug users that has pathologic potential. This organism, however, was found in both seropositive and seronegative individuals in this cohort, suggesting an association with lifestyle rather than serostatus. In addition, data has been published examining the local host response in periodontitis in seropositive individuals. Distinctly elevated levels of IgG in gingival crevicular fluid (GCF) have been observed in seropositive patients. Furthermore, data from our laboratory examining inflammatory mediators in GCF (polymorphonuclear leukocyte lysosomal enzyme beta-glucuronidase and the pro-inflammatory cytokine interleukin-1 beta) suggests an altered response in patients with HIV infection. The alteration manifests as the absence of the expected strong correlation between polymorphonuclear leukocyte activity in the gingival crevice and clinical measures of existing periodontal disease, as well as elevated levels of interleukin-1 beta in sites with deeper probing depths. Therefore, it can be concluded that the progression of periodontal disease in the presence of HIV infection is dependent upon the immunologic competency of the host as well as the local inflammatory response to typical and atypical subgingival microorganisms.

This paper describes steps in the process of evaluating subgingival bacteria assays for the diagnosis of periodontal disease. The first step examines the infectious etiology of periodontal disease in pointing to specific oral bacteria as periodontal pathogens. Second is characterization of the laboratory test to detect and quantitate these pathogens as to sensitivity, specificity, and positive and negative predictive value. Third is the role of the laboratory test in the diagnosis of the different forms of periodontal disease which is related to the current clinical rather than microbiological definition of these diseases. The fourth and most important step is an analysis of the significance of subgingival bacterial tests in clinical decision-making.

The present longitudinal study was designed to explore the long-term efficacy of guided tissue regeneration (GTR) in Class II furcation defects and establish the factors that might be responsible for modifying this response. Subjects with two or more mandibular molars, one of which had Class II furcation defects, received the hygienic phase of therapy followed by baseline clinical measurements and subgingival plaque sampling. GTR procedure was performed in furcation defect sites using expanded polytetrafluoroethylene (ePTFE) membranes, while the other non-furcated molars received only scaling and root planning. Twenty-eight subjects (13 females, 15 males) aged 27 to 66 were included in this longitudinal analysis. Post-surgical treatment included routine home care supplemented with daily chlohexidine rinse and systemic tetracycline. Membranes were retrieved 4 to 6 weeks after surgery. During the first year, patients were initially seen bi-weekly and subsequently monthly for professional prophylaxis. At the end of this year, clinical measurements and samples were obtained. For the next 2 years, patients were seen bi-annually for maintenance visits. Clinical measurements and microbiological samples were then repeated. Next, a tighter maintenance protocol was established and patients were seen quarterly for scaling and oral hygiene reinforcement. Final measurements and samples were taken again 1 year later (4 years postoperative). Significant probing reduction (3.00 mm) and gain in horizontal attachment (2.59 mm) were obtained 1 year postsurgery for the GTR sites. These changes were maintained over 4 years with a slight decline at the end of year 3. Changes in probing depth (PD) from year 1 to 4 served to dichotomize the sites into stable (delta PDor = 0.9 mm), and unstable (PD increaseor = 1 mm). Of the 54 sites available for this analysis only 5 (9.3%) were unstable while 49 (90.7%) were stable or even further improved. Sites which exhibited minimal or no plaque (plaque index [PI]or = 1) over the tight maintenance period had a further decrease in mean probing depth (0.43 mm) compared with a slight increase (-0.06 mm) in mean probing depth in sites with PIor = 2 mm (P = 0.0235). The same phenomenon was observed for changes in relative attachment level (RAL): mean gain in RAL was 0.61 mm compared to 0.25 mm for the 2 groups, respectively (P = 0.07). Actinobacillus actinomycetemcomitans was only isolated from 2 sites at year 3, and none at year 4, compared to 21.45% of the sites at baseline. Porphyromonas gingivalis positive sites showed a continual decline over the years: 14.28% at baseline, 10.71% at year 1, and 5.1% at year 4. On the contrary, Prevotella intermedia (Pi) and Bacteroides forsythus (Bf) infected sites remained at approximately the same rate throughout the 4 years of the study (40% to 50% and 30% to 40% for Pi and Bf, respectively). Of these, Pi-infected sites exhibited less favorable clinical results compared to sites which were not infected with this microorganism. In summary, furcation defects treated with membrane barriers can be maintained in health for at least 4 years; however, good oral hygiene and frequent recall visits as part of a complete anti-infective therapy are essential. Finally, once treated, these teeth are comparable to similar molar teeth with no previous history of furcation pathosis.

The purpose of this study was to assess the prevalence of A. actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia, and their association with periodontal disease states in a population sample from Sri Lanka. Based on clinical parameters, a total of 536 sites in 268 male Sri Lankan tea workers were categorized as healthy, or showing gingivitis only, moderate or advanced periodontitis. Bacterial samples were obtained from all sites and the three target bacteria identified by indirect immunofluorescence. P. intermedia, P. gingivalis and A. actinomycetemcomitans were found in 76%, 40% and 15% of the subjects, respectively. Of the 536 periodontal sites, 10.5% were categorized with "no disease", 14% "gingivitis only": 59% with moderate and 16% with advanced periodontitis. The prevalence of P. gingivalis and P. intermedia was significantly higher in sites with moderate and advanced periodontitis than in sites with no disease or gingivitis only. A. actinomycetemcomitans was not found in healthy sites, but occurred with equal frequency in sites with gingivitis, moderate and advanced periodontitis. The association between these three bacteria and periodontal diseases in Sri Lankan tea laborers was similar to that described for other non-industrialized and industrialized countries.

A total of 325 subjects were entered into a double-blind, stratified 2-treatment clinical study that examined the effects of a dentifrice containing 0.3% triclosan, 2% Gantrez copolymer and 0.243% sodium fluoride on supragingival dental plaque and gingivitis. A subset of 159 subjects including 72 men and 87 women participated in the microbiological component of this study, which was designed to detect shifts in supragingival bacterial species in response to triclosan. Subjects were divided into two groups: one performed normal oral hygiene with the triclosan/copolymer dentifrice and a control group used a placebo dentifrice without triclosan. At baseline, 3 and 6 months during treatment and at 6, 12, 18 and 24 weeks post-treatment, supragingival dental plaque was collected from the buccal and lingual surfaces of the 4 first molar teeth and assayed for: 1) bacterial morphotypes by phase-contrast microscopy; 2) select bacterial groups and bacterial species by culture; and 3) target periodontal pathogens including Actinobacillus actinomycetemcomitans, Bacteroides forsythus, Porphyromonas gingivalis and Prevotella intermedia by immunofluorescence microscopy. There were few statistically significant differences between treatment groups in any of the 90 microbiological parameters measured at the 7 different time points. The control group demonstrated significantly higher levels of cultivable Neisseria and higher proportions at the 3-month treatment period of P. gingivalis-infected subjects and mean cells. After 6 months of treatment, the triclosan group demonstrated higher levels of fusiforms. Analysis of triclosan resistance data failed to detect a shift towards increased proportions of bacteria resistant to triclosan, and both treatment groups demonstrated triclosan-resistant strains, predominantly Veillonella dispar. This study confirms the microbiological safety of triclosan-containing dentifrices and suggests that continued use can be associated with beneficial alterations in the bacterial composition of supragingival dental plaque.

This study examined the risk indicators for alveolar bone loss associated with periodontal infection. A cross-section of 1,361 subjects aged 25 to 74 years, from Erie County, NY were evaluated for interproximal alveolar bone loss and potential explanatory variables including age, gender, history of systemic diseases, smoking, and presence of 8 subgingival bacteria. Interproximal alveolar bone loss was measured from the alveolar crest to the CEJ and a mean computed for each subject. The mean bone loss per subject (BL) ranged from 0.4 to 8.8 mm, and this outcome variable was grouped into 4 ordered categories. The degree of association between the explanatory variables and BL was examined utilizing an ordinal stepwise logistic regression model. Factors which were positively associated with more severe bone loss included subgingival colonization with B. forsythus (O.R. 2.52; 95% CI: 1.98 to 3.17) or P. gingivalis (O.R. 1.73; 95% CI: 1.27 to 2.37), race (Native American, Asian, or Pacific Islanders) with an O.R. 2.40 (95% CI: 1.21 to 4.79), and gender with males having higher odds than females. Smokers had greater odds for more severe bone loss compared to non-smokers ranging from 3.25 (95% CI: 2.33 to 4.54) to 7.28 (95% CI: 5.09 to 10.31) for light and heavy smokers, respectively. Individuals at older ages also showed more severe levels of bone loss. History of kidney disease (O.R. 0.55; 95% CI: 0.35 to 0.89) and history of allergies (O.R. 0.76; 95% CI: 0.59 to 0.98) were inversely associated with severity of bone loss.(ABSTRACT TRUNCATED AT 250 WORDS)

This article describes the baseline findings from a study designed to compare the oral manifestations of HIV infection in homosexual men and intravenous drug users. Both seropositive and seronegative persons were studied. A standard examination instrument was developed to record indexes of oral disease as well as to record the presence of oral lesions. The two groups differed in terms of education, race, socioeconomic status, employment status, housing, and smoking experience. The prevalence and type of oral lesions differed in the two seropositive groups. In seropositive homosexual men, white lesions on the tongue (28.4%) predominated; whereas for the seropositive intravenous drug users, oral candidiasis (43.0%) and gingival marginal erythema (33.3%) were most often detected. We also observed that seronegative intravenous drug users displayed a greater number of oral lesions than seronegative homosexual men. For seropositive homosexual men, lesion presence was significantly associated with decreased levels of CD4; positive associations were seen with current smoking, antiviral drug use, and antibiotic use, and a negative association was observed with current employment. In contrast, only exposure to antiviral drugs was significantly correlated with lesion presence for seropositive intravenous drug users. This baseline analysis from our longitudinal study suggests clear differences in oral manifestations of HIV infection between seropositive homosexual men and intravenous drug users and between seronegative homosexual men and intravenous drug users. Among other parameters, it is apparent that lifestyle, access to health care, and the condition of the oral cavity before infection influence the development of oral lesions in persons with HIV infection.

144 subjects completed a 6-month, double-blind study which examined the effects of a 0.3% triclosan/2% copolymer/0.243% sodium fluoride dentifrice on the microflora of supragingival dental plaque. The subjects were randomly assigned to use, in an oral hygiene program, either the triclosan/copolymer/fluoride test dentifrice or a control dentifrice. The latter had the same formulation as the test dentifrice except it did not contain triclosan. Supragingival plaque was collected from the buccal and lingual surfaces of 4 teeth at baseline, 3 months, and 6 months, and microbiological examined by darkfield microscopy, gram stain morphology', immunofluorescence, and selective and non-selective media. Antimicrobial susceptibilities were determined by agar dilution and whole plaque susceptibility methodologies on plaque samples from 136 subjects at each of the above sample periods and at 6-week intervals for an additional 6 months post-therapy. Both dentifrices resulted in highly statistically significant reductions in the total cultivable flora obtained at both the 3 and 6-month samples relative to baseline as well as at 6 months relative to the 3-month sample. The relative decrease in total anaerobic counts and in strict anaerobes, while not statistically significant, was more pronounced at both the 3- and 6-month sample periods in subjects receiving the triclosan dentifrice than for the controls. Neither dentifrice resulted in detrimental shifts in the microbial composition of the normal flora nor led to the emergence of periodontal or opportunistic pathogens. There was no difference in the relative proportions of the microflora resistance to triclosan or in the number of subjects harboring triclosan-resistant micro-organisms regardless of whether the subjects received the triclosan dentifrice or the control. The proportion of the cultivable flora resistant to triclosan was higher at baseline than at any other sample period. This study demonstrates that the extended use of the 03% triclosan/2% copolymer/fluoride dentifrice does not disrupt the normal microflora associated with supragingival plaque, favor the growth or colonization of periodontal or opportunistic pathogens, or promote the acquisition of microbial resistance.

This study evaluated the effect of periodontal therapy on clinical and microbiological parameters in 23 subjects with severe generalized early onset periodontitis. Therapy consisted of oral hygiene instruction and root planing and scaling, followed 3 months later by open flap debridement. Subjects were monitored for both clinical measures and levels of Actinobacillus actinomycetemcomitans and Porphyromas gingivalis as identified by indirect immunofluoresence. Clinical and microbiological evaluations were done at the start of the study, 3 months after the completion of root planing and scaling and 3 months after open flap debridement. Mean probing depth was reduced by both root planing and scaling and open flap debridement and the level of reduction demonstrated by both phases of therapy was similar to reductions found in studies that utilized subjects with chronic adult periodontitis. In contrast, reductions in attachment level due to the two phases of therapy, demonstrated in previous studies of subjects with adult periodontitis were not found in the young adult subjects with severe periodontal disease utilized in this study. Levels of A. actinomycetemcomitans were not significantly affected by root planing and scaling, but were reduced by open flap debridement. P. gingivalis was virtually eliminated by root planing and scaling, demonstrating that the two bacterial types respond differently to periodontal therapy. These changes in microbiological parameters were similar to those found in studies of localized juvenile periodontitis subjects, where surgery or antibiotics have been shown to be necessary to reduce levels of A. actinomycetemcomitans.

Specific risk indicators associated with either susceptibility or resistance to severe forms of periodontal disease were evaluated in a cross-section of 1,426 subjects, 25 to 74 years of age, mostly metropolitan dwellers, residing in Erie County, New York, and surrounding areas. The study sample exhibited a wide range of periodontal disease experience defined by different levels of attachment loss. Therefore, it was possible to accurately assess associations between the extent of periodontal disease and patient characteristics including age, smoking, systemic diseases, exposure to occupational hazards, and subgingival microbial flora. Age was the factor most strongly associated with attachment loss, with odds ratios for subjects 35 to 44 years old ranging from 1.72 (95% CI: 1.18 to 2.49) to 9.01 (5.86 to 13.89) for subjects 65 to 74 years old. Diabetes mellitus was the only systemic disease positively associated with attachment loss with an odds ratio of 2.32 (95% CI: 1.17-4.60). Smoking had relative risks ranging from 2.05 (95% CI: 1.47-2.87) for light smokers increasing to 4.75 (95% CI: 3.28-6.91) for heavy smokers. The presence of two bacteria, Porphyromonas gingivalis and Bacteroides forsythus, in the subgingival flora represented risks of 1.59 (95% CI: 1.11-2.25) and 2.45 (95% CI: 1.87-3.24), respectively. Our results show that age, smoking, diabetes mellitus, and the presence of subgingival P. gingivalis and B. forsythus are risk indicators for attachment loss. These associations remain valid after controlling for gender, socioeconomic status, income, education, and oral hygiene status expressed in terms of supragingival plaque accumulation and subgingival calculus. Longitudinal, intervention, and etiology-focused studies will establish whether these indicators are true risk factors.

The primary objectives of this double-blind, controlled clinical trial were to assess factor(s) which affect the success of guided tissue regeneration (GTR) procedures in mandibular Class II buccal furcation defects. Thirty subjects, with mandibular Class II furcation defects, were randomly assigned to one of two treatment groups; patients in Group A received oral hygiene instructions with scaling and root planing, while subjects in Group B received similar treatment but without subgingival scaling and root planing at the affected site. After initial oral hygiene instructions and scaling and root planing, GTR surgery was performed using ePTFE barrier membranes. Membranes were retrieved at 6 weeks and subjected to histological examination. Twelve months after regenerative therapy, clinical measurements and re-entry surgical measurements were repeated. Probing reduction (2.61 mm), horizontal probing attachment gain (2.59 mm), and vertical probing attachment gain (0.95 mm) were all significantly better compared to baseline. Likewise, significant improvements in furcation volume (8.0 microliters) and in bone measurements were observed at re-entry. There was no discernible difference between subjects for whom complete anti-infective therapy was deferred to the time of the surgery (Group B) compared to subjects in whom complete anti-infective therapy was performed as part of the hygienic phase of therapy (Group A). Pre-operative pocket depth was directly correlated with the magnitude of attachment gain as well as the amount of new bone formation in the furcation area. Subjects who maintained good oral hygiene and who had minimal gingival inflammation throughout the study demonstrated consistently better regenerative response.(ABSTRACT TRUNCATED AT 250 WORDS)

Dental implants and peri-implant tissue are susceptible to disease conditions that may lead to implant loss. The objective of the present study was to describe teeth and implant surroundings as well as clinical health indices and oral microbiologic parameters.A group of 83 adults (42 men and 41 women) were enrolled in the study. Clinical assessments of dental implants and contralateral natural teeth included dental plaque, gingival inflammation, and bleeding on probing. Microbiologic assessments included bacterial culture, light and phase contrast microscopy, and DNA probe hybridization for a panel of 14 target microorganisms. Clinical and microbiologic data were compared by paired t test and ANOVA. P.05 was considered statistically significant.The Plaque Index for the implants was 1.85 ± 0.47, whereas the score for natural teeth was significantly higher, 2.15 ± 0.52. Compared to the samples obtained from the dental implants, the samples from natural teeth demonstrated significantly higher total bacterial cell numbers (P.05). Consistent with the clinical measures of dental plaque, significantly higher numbers of oral bacteria, including aerobic and anaerobic bacteria, were found in dental plaque samples from teeth (aerobic 5.648 ± 0.512, anaerobic 6.243 ± 0.535, P.0001) compared to implants (aerobic 5.430 ± 0.541, anaerobic 5.917 ± 0.523, P.0001). In addition, there were significantly higher numbers of anaerobic (6.243 ± 0.535 and 5.917 ± 0.523, P.0001) than aerobic (5.648 ± 0.512 and 5.430 ± 0.541, P.008) bacteria for samples from teeth and implants, respectively.Clinical and microbiologic analyses provide consistent findings that suggest differences in quantity of plaque and bacterial species between teeth and dental implants. For long-term treatment success, the importance of plaque control and oral hygiene of both periodontal and dental implant therapy is emphasized.

Previous studies suggest that Solobacterium moorei is associated with oral halitosis. In the present study, we examined the prevalence of S. moorei on the dorsal surface of the tongue in 57 adults (21 with and 36 without halitosis) by bacterial culture and direct amplification of nucleic acids. We also examined the S. moorei type strain and four clinical isolates for 16S ribosomal nucleic acid sequence, H(2)S and enzyme production, and antibiotic susceptibility. S. moorei was found on the dorsal surface of the tongue in 100% of the subjects with halitosis and 14% of subjects without halitosis. Infection with S. moorei was correlated with organoleptic measures of halitosis and with volatile sulfur compound levels. Nucleic acid probe detection of S. moorei as a test for halitosis exhibited 100% sensitivity and 86% specificity. The S. moorei type strain and all four clinical isolates showed98% 16S rDNA sequence similarity, produced H(2)S, demonstrated acid phosphatase, beta-galactosidase, alpha-glucosidase, esterase, leucine arylamidase and naphthol phosphohydrolase enzyme activities, and were sensitive to all antibiotics tested except gentamicin, kanamycin, nalidixic acid and rifampin. This study supports the hypothesis that S. moorei is associated with halitosis.

This case-controlled study examined clinical and microbiological parameters in Brazilian children and adolescents receiving orthodontic treatment using fixed orthodontic appliances or removable orthodontic appliances.The plaque index, gingival index, number of decayed, missing and filled teeth, and probing pocket depth was measured on each fully erupted tooth in 30 patients treated with fixed orthodontic appliances and an equal number of age and sex-matched control subjects. The same parameters were also measured in 18 patients treated with removable orthodontic appliances and an equal number of age and sex-matched control subjects. In the patients treated with fixed orthodontic appliances, subgingival plaque samples were collected from four teeth with orthodontic brackets and from four teeth with orthodontic bands. In the patients with removable appliances, subgingival plaque samples were collected from clasped maxillary permanent first molar teeth and from four unclasped permanent teeth. Samples of unstimulated whole saliva and samples from the dorsal surface of the tongue were also obtained from each subject. Each sample was analyzed for the presence of 19 target bacteria by dot blot. A subset of samples was examined by direct amplification of bacterial nucleic acids.Compared to their respective age and sex-matched controls, whole mouth means for plaque index and gingival index were significantly elevated in both the fixed and removable orthodontic groups. There was no difference in the DMFT. Subjects with fixed orthodontic appliances had a higher prevalence of each of the target species except for L. fermentum, Neisseriaceae and S. mutans. The prevalence of A. naeslundii and Streptococcus sp. was significantly higher on teeth with orthodontic brackets alone compared to teeth with both orthodontic bands and brackets. Subjects with removable orthodontic appliances had a higher prevalence of A. actinomycetemcomitans, C. rectus, E. corrodens, L. fermentum, Neisseriaceae, and spirochetes. The prevalence of Neisseriaceae was significantly higher on unclasped teeth compared to clasped teeth. There was no difference between sample sites for the target bacteria except for A. actinomycetemcomitans that was detected less frequently in saliva. Orthodontic patients demonstrated higher proportions of gram negative species by direct amplification of nucleic acids including species frequently associated with periodontal disease as well as rarely cultivable or non-cultivable species such as Abiotrophia defectiva, Gemella haemolysans, Granulicatella adiacens, Lautropia sp., Terrahaemophilus aromaticivorans, and TM7 bacterium.

In vitro testing of antimicrobial agents is an important tool in the testing hierarchy, and may provide interesting insights into their potential clinical efficacy. Agents with demonstrable in vitro antimicrobial activity may be effective against the same microorganisms in vivo, whereas agents without demonstrable in vitro antimicrobial activity are unlikely to exhibit in vivo antimicrobial activity. In addition, these methods may also be useful in screening antimicrobial agents in product formulations because such agents with both in vitro and in vivo activity may have reduced antimicrobial effects when formulated into a dentifrice. Accordingly, this study examined the in vitro and ex vivo antimicrobial activity of three commercial dentifrices: one formulated with 0.243% sodium fluoride (Crest Cavity Protection Toothpaste-Regular); one with 0.454% stannous fluoride, sodium hexametaphosphate, and zinc lactate (Crest Pro-Health), and one with 0.3% triclosan, 2.0% PVM/MA copolymer, and 0.243% sodium fluoride (Colgate Total).The minimum inhibitory concentration (MIC) of each dentifrice was determined for resident oral bacterial species, including bacteria that are associated with dental caries; periodontitis, and oral halitosis. Evaluations were performed on individual laboratory strains, and on oral bacteria from supragingival plaque samples obtained from 10 adults and from oral rinse samples obtained from 18 adults.The lowest MICs against the oral strains and human samples, i.e., greatest antimicrobial activity, were seen for the triclosan/ copolymer dentifrice. There was, in general, a four-fold difference in MICs between the triclosan/copolymer dentifrice and the stannous fluoride/sodium hexametaphosphate/zinc lactate dentifrice. The triclosan/copolymer dentifrice significantly inhibited periodontal pathogens, such as Aggregatibacter actinomycetemcomitans, Eikenella corrodens, and Fusobacterium nucleatum. In ex vivo tests measuring antimicrobial effects, the triclosan/copolymer dentifrice substantially inhibited bacterial growth after 30-, 60-, and 120-second exposures compared to the sodium fluoride or stannous fluoride/sodium hexametaphosphate/zinc lactate dentifrices. Similarly, in ex vivo tests measuring antimicrobial effects on supragingival plaque biofilms, the triclosan/copolymer dentifrice substantially inhibited bacterial growth compared to the other test dentifrices.Different in vitro and ex vivo analyses show that the triclosan/copolymer dentifrice has significant antimicrobial activity on oral bacteria, including species causing dental caries, periodontitis, and oral halitosis, and it provides superior efficacy compared to the stannous fluoride/sodium hexametaphosphate/zinc lactate dentifrice.

The purpose of the present study was to evaluate the effect of anti-infective therapy on the success of periodontal regeneration in mandibular Class II furcation defects. Eighteen patients with mandibular bilateral Class II furcation defects were enrolled. Following an initial hygienic phase, guided tissue regeneration (GTR) was performed using an expanded polytetrafluoroethylene (e-PTFE) membrane barrier. The area was surgically exposed, thoroughly root planed, and irrigated with either tetracycline (100 mg/ml) or 0.9% saline. Post-operative care included systemic tetracycline (250 mg q.i.d.) and chlorhexidine 0.12% mouthwash twice daily. Patients were maintained on a prophylaxis schedule of every 2 weeks for the first 3 months, and monthly thereafter. Clinical parameters of probing depth (PD), probing attachment level - vertical (PAL-v), probing attachment level - horizontal (PAL-h), and target periodontal pathogens were monitored at baseline and quarterly for one year. An overall improvement in all clinical parameters was observed in both groups: probing reduction (3.1 mm), PAL-h gain (2.3 mm), and PAL-v gain (1.2 mm) were all statistically significant compared to baseline measurements. Vertical measurements were performed parallel to the long axis of the tooth with no attempt to angulate the probe into the furcation. There was no significant difference in sites receiving tetracycline. A strong positive correlation was noted between initial PD and pocket reduction (r = 0.77, P < 0.0001) and between initial PD and PAL-h gain (r = 0.54) and PAL-v gain (r = 0.45) suggesting that initial probing depth might be used to assess the regenerative potential of a given site.(ABSTRACT TRUNCATED AT 250 WORDS)

Fourteen human periodontal isolates recovered from a purported Eikenella corrodens-selective medium containing 1 μg of clindamycin per ml displayed biochemical traits which differed from those described for E. corrodens. These organisms were gram-negative rods which corroded agar. The isolates were oxidase positive and urease, indole, and esculin negative. They differed from E. corrodens in catalase, nitrate reduction, lysine decarboxylase, and ornithine decarboxylase activities. One isolate, strain UB-294, was presumptively identified as Kingella denitrificans. A second isolate, strain UB-204, differed from E. corrodens by being catalase positive and nitrate reduction negative. Twelve isolates, including strain UB-38T (T = type strain), were phenotypically similar to Kingella kingae except that they did not produce acid from maltose and were not beta-hemolytic. Essentially complete (1,480-base) 16S rRNA sequences were determined for strains UB-38T, UB-204, and UB-294 and the type strains of Neisseria animalis, Neisseria canis, Neisseria denitrificans, Neisseria elongata, Neisseria flavescens, Neisseria macaca, and Neisseria polysaccharea. These sequences were compared with the previously published sequences of six other species belonging to the family Neisseriaceae. On the basis of the results of the comparative sequence analysis, UB-294 was confirmed as a K. denitrificans strain, UB-204 was identified as a member of a new species which may belong in the genus Eikenella, and UB-38T was identified as a member of a new species of the genus Kingella, for which we propose the name Kingella orale. Since strain UB-204 was the only representative of a new species, it was not named. DNA probes for identification of E. corrodens, K. denitrificans, and K. orale based on 16S rRNA sequence information are described.

The current study assessed the clinical and microbiological effects of systemic antimicrobial therapy alone in Actinobacillus actinomycetemcomitans-infected adolescents with periodontal disease. The study involved 6 localized juvenile periodontitis patients 13-18 years of age, who harbored high numbers of A. actinomycetemcomitans in subgingival plaque samples. The periodontal lesions were microbiologically monitored by selective culture, and clinically assessed for probing pocket depth and periodontal attachment level 3 months prior to baseline, and at 3, 6, 12, and 24 months posttreatment. Tetracycline-HCl (250 mg/QID) was prescribed until 1 week after subgingival A. actinomycetemcomitans was no longer detectable or for a maximum of 8 weeks. During 3 months prior to treatment, pocket depth was unchanged, and was then significantly reduced from an average of 7.1 mm to 5.1 mm 12 months after treatment (p = 0.02). The mean change in clinical attachment level was a gain of 1.4 mm between baseline and 12 months (p = 0.02). 3 of the 6 patients were still infected with A. actinomycetemcomitans after 8 weeks of antibiotic therapy and 4 subjects were infected at 12 months. Numbers of A. actinomycetemcomitans were still suppressed in most lesions. There was a strong association between mean numbers of A. actinomycetemcomitans in periodontal pockets and mean change in probing attachment level at any given time point. For 22 available comparisons, derived from all time points, there was a strong association (r = 0.68) between subgingival A. actinomycetemcomitans and change in probing attachment level.(ABSTRACT TRUNCATED AT 250 WORDS)

Previously, we reported the antigranulocytic activity of Campylobacter rectus media supernatants containing lipopolysaccharide (LPS) and a 104 kDa protein. Here, we monitored the release of protein and LPS through the growth cycle of C. rectus ATCC 33238 and identified the 104 kDa protein as the cytotoxin. LPS in media supernatants was quantitated by a KDO assay; the 104 kDa protein was detected on immunoblots with specific antibody (A104) and quantitated by amino acid analysis of membrane immobilized protein bands. C. rectus cell product release was independent of cell lysis, Over 24 h, the 104 kDa protein was released linearly while LPS was released in two plateaus; both increased in C. rectus culture supernatants 3 h after inoculation achieving maximum concentrations at 21 h of 3.1 μg/ml and 14.6 μg/ml, respectively, In 2 h, trypan blue viability assays, 37-47 μg of 12, 18 and 24 h supernatant protein killed 33-43% of HL-6O cells. Supernatant toxicity was heat sensitive and inhibited by A104. Sequencing the 16 N-terminal amino acids of the cytotoxin distinguished it from described C. rectus proteins, Similarities between epitopes and amino acid compositions of the Actinobacillus actinomycetemcomitans leukotoxin and C. rectus cytotoxin were observed. These data indicate that C. rectus secretes a 104 kDa cytotoxin.

Clinical measurements of periodontal attachment loss, while not always representing the histological changes, are used to establish the diagnosis of adult periodontitis. Such measurements are difficult to perform accurately and are labor intensive. To counter these problems, index teeth and index sites have been employed in an attempt to estimate the severity of the periodontal condition without the need to resort to elaborate attachment measurements. Unfortunately, such indices usually tend to underestimate prevalence while often overestimating severity. The purpose of the present study was to examine the correlation of alternative clinical, radiographic and microbiological parameters, with periodontal disease using the diagnostic criteria of established periodontitis. 508 adults included in this study received thorough periodontal examination which included probing pocket depth, clinical attachment level, plaque, gingival and calculus scores, together with radiographic analysis and assays of subgingival periopathogenic microorganisms. Radiographic alveolar bone loss and probing pocket depth had the highest correlation with clinical attachment loss (phi = 0.72 and phi = 0.75 respectively). Plaque scores (phi = 0.17), like gingival scores (phi = 0.06) and calculus scores (phi = 0.42) had poor correlation with established periodontitis. Periodontopathogenic species demonstrated high specificity and negative predictive values; but low sensitivity and positive predictive values make for an overall low correlation of these species with established periodontitis. However, when used in a logistic regression model, the presence of P. gingivalis (odds ratio = 6.25) has shown to contribute significantly to the estimate of probability for established periodontitis. The use of these various alternative parameters for screening of periodontal disease is discussed in light of their sensitivity, specificity and predictive value.

Supportive therapy to maintain dental implants is increasingly important. This study examined the effect of a 0.3% triclosan/2% copolymer dentifrice on oral biofilms and gingival inflammation (GI) on dental implants and peri-implant tissues.One hundred and twenty adults with a dental implant and contra-lateral tooth were enrolled in this 6 month, double-blind, two-treatment, parallel group study. Sixty subjects were randomly assigned to a triclosan/copolymer dentifrice test group and 60 subjects to a fluoride dentifrice control group and instructed to brush twice daily for 6 months. At baseline, 3, and 6 months, a calibrated dentist assessed dental plaque, GI and collected supragingival dental plaque for microbiological analysis.Subjects in the triclosan/copolymer group demonstrated significantly lower levels of dental plaque, gingivitis, and bleeding on probing at 3 and 6 months at both the implant and contra-lateral tooth compared with the fluoride group (p0.05). There were significantly fewer Gram-negative anaerobes in the triclosan/copolymer group (p0.05) including90% reductions in Aggregatibacter actinomycetemcomitans, Campylobacter rectus, Eubacterium saburreum, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella melaninogenica, Solobacterium moorei, and Tannerella forsythia.Twice daily use of a triclosan/copolymer dentifrice may enhance dental implant maintenance by reducing dental plaque and GI.

This investigation compared the effects of a fluoride dentifrice and toothpastes formulated with antimicrobial ingredients (stannous fluoride and triclosan/copolymer) on oral micro-organisms, including those found in samples taken from the human oral cavity. Microbiological techniques determined the minimum inhibitory concentrations (MICs) of each dentifrice necessary to inhibit the growth of bacterial strains from the healthy oral cavity, as well as those found in dental caries, periodontal disease, and halitosis. Ex vivo studies utilized oral rinse samples and supragingival plaque from adults to determine antimicrobial effects on the entire microbial diversity of these samples, including biofilm-derived micro-organisms. The triclosan/copolymer dentifrice demonstrated the lowest MICs and significantly inhibited Gram-positive and Gram-negative bacteria (including the periodontal pathogens Aggregatibacter actinomycetemcomitans, Eikenella corrodens, and Fusobacterium nucleatum). In the ex vivo tests, the triclosan/copolymer dentifrice demonstrated substantial inhibition in the oral rinse samples over each treatment period (p0.0005) as compared to either the fluoride or stannous fluoride dentifrices. Similarly, the triclosan/copolymer dentifrice demonstrated the highest inhibition of micro-organisms in the supragingival plaque biofilm (p0.0005). No significant differences were observed between the fluoride and stannous fluoride dentifrices (p0.5).

A great deal of controversy has existed in the periodontal literature as to whether the site or the subject should be the unit of analysis. Using the site as the unit of analysis assumes that observations of sites within the same subject are independent and ignores between subject variation. The purpose of this report is to evaluate the influence that the unit of analysis has on estimating the number of necessary site specific bacterial samples from each subject. The number of bacterial samples per subject was defined as the number of samples that would insure a clinician at a 95% confidence level that, if the bacteria were present in a subject, it would be discovered. From two data sets in which 20 to 30 bacterial samples were taken from each subject and data generated from a simulation, appropriate within-subject sample size was determined. In one data set the presence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Bacteroides forsythus, and Prevotella intermedia was determined by indirect immunofluorescence. In the other data set the presence of A. actinomycetemcomitans, P. gingivalis, and P. intermedia was determined using DNA probes. Results of this study demonstrate that there is a large between subject variation in site specific bacterial prevalence, as indicated by an elevated intraclass correlation. Simulated data in this report demonstrated that the number of necessary bacterial samples per subject increased with increasing values of intraclass correlation. The number of necessary within subject samples also increased with decreasing prevalence rate. For A. actinomycetemcomitans, which had a low prevalence rate (0.11 to 0.18), the number of necessary samples per subject was very high (31 to 35).(ABSTRACT TRUNCATED AT 250 WORDS)

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)

The ATCC type strain and six clinical isolates of Campylobacter rectus were tested for toxicity against HL-60 cells and human polymorphonuclear neutrophils (PMNs). After challenge with bacterial cell suspensions and media supernatants for up to 4 h, eukaryotic cell viability was assayed by trypan blue dye exclusion and lactate dehydrogenase release. Cells of the C. rectus type strain were not toxic. However, ethanol and (NH4)2SO4 extracts of culture media supernatants killed HL-60 cells in a time and dose dependent manner with 700 micrograms of supernatant protein killing 100% of HL-60 cells in 4 h. Concentrated media supernatants from clinical isolates also killed 100% of HL-60 cells in 30 to 60 min. The bacterial culture supernatants were toxic to PMNs with clinical isolates killing 70 to 90% of PMNs in 2 to 4 h. SDS-PAGE and immunoblot analysis of the toxic media supernatants revealed C. rectus specific proteins and lipopolysaccharide (LPS). The toxic activity was inhibited by protease, indicating that the toxin was protein. Non-toxic and toxic media supernatants were obtained by altering hemin and fumarate in the growth media. SDS-PAGE analysis of these revealed that all toxic supernatants contained a 104 kDa protein.

Antony van Leeuwenhoek first described oral bacteria. However, not until almost 200 years later was the famous Koch postulate introduced. Since then, research has extensively been performed regarding the development and microbiology of dental plaques. In spite of the complexity of the developing flora of supragingival plaque, culture studies have shown a remarkably orderly succession of organisms. Lately, the concept of microbial specificity in the etiology of periodontal diseases has been widely suggested, i.e., that different forms of periodontal disease are associated with qualitatively distinct dental plaques. Cross-sectional and longitudinal studies of the predominant cultivable microflora reveal that only a small number of the over 300 species found in human subgingival plaques are associated with periodontal disease. Among the commonly mentioned are: Actinobacillus actinomycetemcomitans, Bacteroides gingivalis, Bacteroides intermedius, Capnocytophaga sp., Eikenella corrodens, Fusobacterium nucleatum, and Wolinella recta, as well as certain gram-positive bacteria such as Eubacterium species. Anti-infective therapy for many systemic infections equals the use of antimicrobial drugs. However, for localized infections like periodontal diseases, treatment may consist of a combination of mechanical wound debridement and the application of an antimicrobial agent. The general effectiveness of mechanical anti-infective therapy and successful oral hygiene in the management of periodontal disease is well established in the literature and has met the test of success in clinical practice for most cases of periodontitis in adults. The definition of periodontal pathogens as either opportunistic pathogens, or as exogenous pathogens carries with it significant implications.(ABSTRACT TRUNCATED AT 250 WORDS)

Ribosomal RNA (rRNA) isolated from Wolinella recta and seven related bacteria was examined by agarose gel electrophoresis. The 23S rRNA molecule could not be detected in W. recta, Wolinella curva, Bacteroides gracilis, or Bacteroides ureolyticus. In place of the 23S molecule, there were three smaller molecules of approximately 1700, 650, and 600 bases designated 23Sa, 23Sβ, and 23S∂, respectively. An intact 23S rRNA molecule could be isolated from Wolinella succinogenes, Campylobacter concisus, and Campylobacter sputorum. The cleavage sites of the W. recta 23S rRNA molecule were located by direct RNA sequence analysis and were found to be in similar locations, nucleotides 546 and 1180, as cleavage sites described in other prokaryotes. The presence or absence of the 23S rRNA molecule may be a useful marker for these micro-organisms.

The potential of Wolinella recta and Actinobacillus actinomycetemcomitans to cause abscesses and induce an immune response was tested in BALB/c mice. Mice were injected subcutaneously with W. recta, A. actinomycetemcomitans or a mixture of these 2 microorganisms. Mice injected with A. actinomycetemcomitans alone, or with both organisms, demonstrated abscesses at the injection site 2 days later, from which pure cultures of A. actinomycetemcomitans were isolated. Mice injected with W. recta had small, flat abscesses at the injection site from which no bacteria could be cultured. W. recta was cultured from injection sites only when associated with A. actinomycetemcomitans. Mice developed positive serum IgG antibody responses to W. recta by 20 days post-injection but not to A. actinomycetemcomitans whether injected in pure culture or mixed infection. In vitro lymphoproliferative responses following injection of W. recta and/or A. actinomycetemcomitans resulted in increased lymphocyte reactivity in unstimulated cultures and decreased in vitro responses to phytohemagglutinin. In vitro lymphoproliferative responses to Escherichia coli LPS or Salmonella typhimurium LPS were depressed in mice injected with A. actinomycetemcomitans, but not in mice injected with W. recta.