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Background Clinical research has shown a relationship between microbial accumulations and oral diseases such as gingivitis and caries. The mouth harbors large densities of bacteria in distinct oral microenvironments, that is, dental plaque on teeth, saliva, and soft tissues such as the tongue, cheek, and gingiva. In this home-use study, the authors compared the effects of brushing with a newly formulated stannous fluoride toothpaste and a sodium monofluorophosphate dentifrice on bacteria of distinct oral microenvironments. Methods Adult participants completed a washout phase before baseline sampling of dental plaque, saliva, and scrapings from tongue, cheek, and gingiva, which were used for microbiological analysis. Treatments were randomly assigned: test (62 participants) and control (67 participants) for twice-daily toothbrushing over 8 weeks. After 4 weeks and 8 weeks, posttreatment samples 12 hours after brushing were collected for analysis. At these posttreatment visits, participants brushed in the dental clinic, and an additional sample was collected 4 hours later for microbiological analysis. Results Relative to the control, 12 hours after brushing, the test toothpaste showed greater reductions of bacteria (ranging from 14% to 27%) at the 4-week evaluation, which increased to 27% to 41% after 8 weeks of brushing. Correspondingly, 4 hours after brushing with the test toothpaste at the 4-week evaluation, there were greater reductions of bacteria in the range of 22% to 59%, which increased to a range of 33% to 61% at the 8-week assessment for participants completing the study. Conclusions The stannous fluoride toothpaste provided bacterial reductions in all oral microenvironments 12 hours after brushing. In addition, the authors observed microbial reductions 4 hours after brushing, which increased after extended use. Practical Implications The results are appropriate for oral hygiene recommendations by dental professionals.

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.

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

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

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.

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.

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).

Actinobacillus actinomycetemcomitans leukotoxin is thought to be an important virulence factor in the pathogenesis of localized juvenile and other forms of early-onset periodontitis. Some highly leukotoxic A. actinomycetemcomitans strains produce 10 to 20 times more leukotoxin than other minimally leukotoxic strains. The distribution, clonality, and intrafamilial transmission of highly leukotoxic A. actinomycetemcomitans were examined in order to determine the importance of leukotoxin in the pathogenesis of periodontitis.The polymerase chain reaction (PCR) was used to differentiate highly leukotoxic from minimally leukotoxic strains in examining 1,023 fresh A. actinomycetemcomitans isolates and strains from our culture collection. These were obtained from 146 subjects including 71 with localized juvenile periodontitis (LJP), 4 with early-onset periodontitis, 11 with post-localized juvenile periodontitis, 41 with adult periodontitis, and 19 periodontally normal subjects. The arbitrarily primed polymerase chain reaction (AP-PCR) analysis of 30 oral isolates from each of 25 subjects was used to determine the intraoral distribution of A. actinomycetemcomitans clones. AP-PCR was also used to examine the transmission of A. actinomycetemcomitans in 30 members of 6 families. The clonality of 41 highly leukotoxic A. actinomycetemcomitans strains was evaluated by both AP-PCR and ribotyping.Highly leukotoxic A. actinomycetemcomitans was found only in subjects with localized juvenile and early-onset periodontitis. Fifty-five percent of the LJP subjects harbored highly leukotoxic A. actinomycetemcomitans isolates. Seventy-three percent of the A. actinomycetemcomitans isolates in these subjects were highly leukotoxic. Highly leukotoxic A. actinomycetemcomitans infected younger subjects (mean age 13.95 years, range 5 to 28 years) than minimally leukotoxic (mean age 35.47 years, range 6 to 65 years). Most subjects were infected with only one A. actinomycetemcomitans genotype. However, PCR of whole dental plaques and subsequent analysis of up to 130 individual oral isolates suggested a possible shift in A. actinomycetemcomitans over time in that a few subjects harbored both highly leukotoxic and minimally leukotoxic strains. AP-PCR analysis was consistent with intrafamilial A. actinomycetemcomitans transmission. Ribotyping and AP-PCR analysis confirmed a previous report that highly leukotoxic A. actinomycetemcomitans consists of a single clonal type.This study suggests that localized juvenile and other forms of Actinobacillus-associated periodontitis are primarily associated with the highly leukotoxic clone of A. actinomycetemcomitans.

Background Triclosan is a broad-spectrum antimicrobial agent used in toothpaste to reduce dental plaque, gingivitis and oral malodor. This community-level assessment evaluated the susceptibility of dental plaque bacteria to triclosan in samples collected over 19 years. Methods A total of 155 dental plaque samples were collected at eleven different times over 19 years from 58 adults using 0.3% triclosan, 2% copolymer, 0.243% sodium fluoride toothpaste and from 97 adults using toothpaste without triclosan. These included samples from 21 subjects who used triclosan toothpaste for at least five years and samples from 20 control subjects. The samples were cultured on media containing 0, 7.5 or 25 μg/ml triclosan. Descriptive statistics and p values were computed and a linear regression model and the runs test were used to examine susceptibility over time. Results Growth inhibition averaged 99.451% (91.209 - 99.830%) on media containing 7.5 μg/ml triclosan and 99.989% (99.670 - 100%) on media containing 25 μg/ml triclosan. There was no change in microbial susceptibility to triclosan over time discernible by regression analysis or the runs test in plaque samples taken over 19 years including samples from subjects using a triclosan-containing dentifrice for at least five years. Conclusions This community-level assessment of microbial susceptibility to triclosan among supragingival plaque bacteria is consistent with the long-term safety of a 0.3% triclosan, 2% copolymer, 0.243% sodium fluoride dentifrice.