Search

Background People with COPD have been reported to bear a distinct airway microbiota from healthy individuals based on bronchoalveolar lavage (BAL) and sputum samples. Unfortunately, the collection of these samples involves relatively invasive procedures and is resource-demanding, limiting its regular use. Non-invasive samples from the upper airways could constitute an interesting alternative, but its relationship with COPD is still underexplored. We examined the merits of saliva to identify the typical profile of COPD oral bacteria and test its association with the disease. Methods Outpatients with COPD and age-sex matched healthy controls were recruited and characterised based on clinical parameters and 16S rRNA profiling of oral bacteria. A clustering analysis based on patients’ oral bacteria beta-diversity and logistic regressions were performed to evaluate the association between oral bacteria composition and COPD. Results 128 individuals participated (70 patients and 58 controls). Differential abundance analyses showed differences in patients comparable to the ones previously observed in samples from the lower respiratory tract, i.e., an increase in Proteobacteria (particularly Haemophilus) and loss of microbiota diversity. An unsupervised clustering analysis separated patients in two groups based on microbiota composition differing significantly in the frequency of patients hospitalized due to severe acute exacerbation of COPD (AECOPD) and in the frequency of GOLD D patients. Furthermore, a low frequency of Prevotella was associated with a significantly higher risk of recent severe AECOPD and of being GOLD D. Conclusion Salivary bacteria showed an association with COPD, particularly with severe exacerbations, supporting the use of this non-invasive specimen for future studies of heterogeneous respiratory diseases like COPD.

Aim: The purpose of this prospective study was to determine if there is a difference in number and distribution of salivary bacteria between patients with tonsillar infection and healthy volunteers. Background: The etiology of peritonsillar abscess (PTA) is unclear. Smoking, periodontal disease, and infection of minor salivary glands have been suggested as predisposing factors for PTA. Material and methods: Patients with acute tonsillitis (AT) (n = 54), peritonsillitis (PT) (n = 36), PTA (n = 58), and healthy volunteers (n = 52) were prospectively recruited and evaluated. Saliva bacteria were analyzed with flow cytometry. Patients and their treating physicians completed a questionnaire about patients' current disease, smoking habits, alcohol consumption, and oral health. Results: There were no differences in the total number of saliva bacteria between patients with acute throat infection and healthy volunteers (p = .104) or between AT, PT, and PTA patients (p = .273). Smoking habits, alcohol consumption, oral hygiene, or prior antibiotics had no effect on total amount of salivary bacteria in patients with acute throat infection. Conclusions: The effects of smoking on salivary bacteria do not seem to be the mechanism that promotes development of PTA in smokers.

Aim: The purpose of this study was to create an alternative protocol for the DNA-based identification of salivary microbiota focused on the distinguishing of Streptococcus species. Materials & methods: Salivary bacteria were identified using 16S rDNA sequencing and proteins and lipids profiling using MALDI-TOF/MS as well as FTIR analysis. Results: Most of the isolates belonged to streptococci - mostly the salivarious group indistinguishable by the molecular technique. In turn, MALDI analysis allowed for their fast and reliable classification. Although FTIR spectroscopy demonstrated the correct species classification, the spectra interpretation was time consuming and complicated. Conclusion: MALDI-TOF/MS demonstrated the biggest effectiveness in the identification and discrimination between the salivary streptococci, which could be easily incorporated in the workflow of routine microbiological laboratories.

Microbial biofilms developed on dental implants play a major role in perimplantitis' pathogenesis. Many studies have indicated that surface roughness is the main feature favoring biofilm development in vitro, but its actual influence in vivo has still to be confirmed. In this study, the amount of biofilm formed on differently treated titanium surfaces, showing distinct roughness, has been examined both in vivo and in vitro by Confocal Laser Scanning Microscopy. In vitro studies availed of biofilm developed by Pseudomonas aeruginosa or by salivary bacteria from volunteer donors. In vivo biofilm production was obtained by exposing titanium discs to the oral cavity of healthy volunteers. In vitro experiments showed that P. aeruginosa and, to a lesser extent, salivary bacteria produce more biomass and develop thicker biofilms on laser-treated and sandblasted titanium surfaces with respect to machined ones. In vivo experiments confirmed that bacterial colonization starts on sites of surface unevenness, but failed to disclose biomass differences among biofilms formed on surfaces with different roughness. Our study revealed that biofilm developed in vitro is more easily influenced by surface features than biofilm formed by complex communities in the mouth, where the cooperation of a variety of bacterial species and the presence of a wide range of nutrients and conditions allow bacteria to optimize substrate colonization. Therefore, quantitative differences observed in vitro among surfaces with different characteristics may not be predictive of different colonization rates in vivo.

Background: Pluchea indica (L.) Less leaf contains antibacteria substances that can inhibit the growth of bacteria that cause dental and oral diseases. Previous research shows that Pluchea indica (L.) Less leaf extract can inhibit the growth of Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa bacteria. This research aimed to find out effectiveness of Pluchea indica (L.) Less leaves to decrease in the number of salivary bacteria colony. Method: This research used a sample of saliva obtained from a person who has dental caries. The saliva had been treated with Pluchea indica (L.) Less leaves ethanol extract with concentration 2,5%, 3,5%, 4,5%, 5,5%, and 6,5%. Bacterial colonies were calculated using a colony counter and no identification was performed. Result: The mean of bacteria colony number in Plate Count Agar media without Pluchea indica (L.) Less leaves ethanol extract is 142,67. After being given Pluchea indica (L.) Less leaves ethanol extract with concentration of 2,5%, 3,5%, and 4,5%, the mean of bacteria colony number sequentially are 15,67, 10,67, 4, and at a concentration of 5.5% and 6.5% no more bacterial colonies were found. Conclusion: Pluchea indica (L.) Less leaves ethanol extract effective to inhibit and eliminate oral bacteria.

Objective: The objective of this study was to investigate the differences activity of salivary Streptococcus mutans bacteria in children suffer acute lymphoblastic leukemia (ALL) in phase of chemotherapy, induction, intensification/consolidation, and maintenance.Methods: This study was a laboratory observational, and cross-sectional method, conducted 19 ALL children in phase of chemotherapy, induction, intensification/consolidation, and maintenance. 2 mm of dental plaque was collected from mesiobuccal first permanent molar and incubated for 48 h at 37°C, and the bacterial activity of S. mutans measured by Cariostat.Results: Odds ratio analysis among chemotherapy phase of induction, intensification/consolidation, and maintenance is not significant (p>0.05) differences.Conclusion: The highest activity bacteria of S. mutans were found in the induction phase

A clinical procedure was developed to examine the effects of short-term and extended use of a triclosan/copolymer dentifrice and a commercial fluoride dentifrice on oral bacteria, including those producing hydrogen sulfide. Healthy adults volunteered for this double-blind, crossover design clinical study and provided saliva samples for culturing on enriched and indicator media to enumerate all salivary bacteria and those producing hydrogen sulfide (odorigenic), respectively. Subjects brushed with an assigned dentifrice for 7 d and were sampled on day 8 to assess the long-term effects on bacteria. Extended use of the triclosan/copolymer dentifrice resulted in a 49% and 66% reduction of salivary and odorigenic bacteria, respectively, compared with the fluoride dentifrice. To examine short-term effects, subjects subsequently brushed with their assigned dentifrice and were sampled at 2 h and 4 h post-brushing. At 2 h and 4 h post-brushing, the triclosan/copolymer dentifrice resulted in a 62% and 52% decrease for salivary bacteria and 79% and 72% decrease for odorigenic bacteria, respectively, vs. the fluoride dentifrice. The results indicate a significant decrease of all salivary bacteria and hydrogen sulfide-producing odorigenic bacteria following use of the triclosan/copolymer dentifrice and explain previous results on the efficacy of this dentifrice on oral malodor.

The in vivo antimicrobial activity of 0.12% and 0.2% chlorhexidine (CHX) on the salivary flora up to 7 h after its application, using epifluorescence microscopy with the SYTO 9/propidium iodide dual staining, was evaluated. Fifteen volunteers performed a single mouthrinse with sterile water (SM-water), a single mouthrinse with 0.12% CHX (0.12% SM-CHX) and a single and double mouthrinse with 0.2% CHX (0.2% SM-CHX and 0.2% DM-CHX). Samples of saliva were taken at 30 s, and 1, 3, 5, and 7 h after each application. In comparison with SM-water, 0.2% CHX (SM and DM) showed a significant antibacterial effect up to 7 h after the mouthrinse, whereas this effect only persisted up to 5 h after the 0.12% SM-CHX mouthrinse. On comparing the two concentrations of CHX, significantly higher percentages of bacterial vitality were observed in all the saliva samples after the use of 0.12% CHX than after 0.2% CHX. On comparison of the 0.2% SM-CHX and 0.2% DM-CHX, significantly higher percentages of live bacteria were observed in the saliva samples taken at 1, 3, 5, and 7 h after the single mouthrinse compared with the double mouthrinse. The 0.2% CHX mouthrinse had the greatest antimicrobial activity on the salivary flora up to 7 h after its application, with a progressive recovery in bacterial vitality. The differences observed with respect to the 0.12% CHX mouthrinse demonstrate the influence of the concentration on its immediate antimicrobial activity and substantivity.

During the months of November 1996, August 1997, and March 1998, saliva and plasma samples were collected for isolation of aerobic bacteria from 26 wild and 13 captive Komodo dragons (Varanus komodoensis). Twenty-eight Gram-negative and 29 Gram-positive species of bacteria were isolated from the saliva of the 39 Komodo dragons. A greater number of wild than captive dragons were positive for both Gram-negative and Gram-positive bacteria. The average number of bacterial species within the saliva of wild dragons was 46% greater than for captive dragons. While Escherichia coli was the most common bacterium isolated from the saliva of wild dragons, this species was not present in captive dragons. The most common bacteria isolated from the saliva of captive dragons were Staphylococcus capitis and Staphylococcus capitis and Staphylococcus caseolyticus, neither of which were found in wild dragons. High mortality was seen among mice injected with saliva from wild dragons and the only bacterium isolated from the blood of dying mice was Pasteurella multocida. A competitive inhibition enzyme-linked immunosorbent assay revealed the presence of anti-Pasteurella antibody in the plasma of Komodo dragons. Four species of bacteria isolated from dragon saliva showed resistance to one or more of 16 antimicrobics tested. The wide variety of bacteria demonstrated in the saliva of the Komodo dragon in this study, at least one species of which was highly lethal in mice and 54 species of which are known pathogens, support the observation that wounds inflicted by this animal are often associated with sepsis and subsequent bacteremia in prey animals.

This study evaluated the effect of an alternate delivery system for chlorhexidine on salivary levels of mutans streptococci (MS) and other selected oral bacteria. On the basis of salivary MS levelsor = 10(4) CFU/ml, 22 subjects were enrolled. All caries lesions were restored prior to treatment. Two pretreatment paraffin-stimulated saliva samples were obtained for culturing at least 1 week apart. Complete-arch vacuum-adapted mouthguards were individually fabricated and coated internally with a 3% w/v chlorhexidine varnish. Mouthguards were worn for an average of 7 h/night for 7 nights. Saliva samples were obtained immediately after treatment and 1 and 3 months later. There was no significant change in levels of any of the monitored bacteria between the two pretreatment samples. A significant and specific reduction in salivary MS levels was observed in the three after-treatment samples as compared with baseline values (p0.001, p0.001, p0.05, respectively). The levels of Actinomyces viscosus were also measured, and there was a significant reduction immediately after treatment (p0.05), a return to baseline values at 1 month, and a significant increase above baseline values at 3 months, (p0.001). There was no significant change in saliva volume, in total numbers of facultatively anaerobic bacteria, or in levels of lactobacilli or Streptococcus sanguis. This treatment system is capable of significant and specific suppression of MS levels for up to 3 months without retreatment.

The purpose of this study was to assess the effect of pre-procedural rinsing (2 consecutive rinses) with 0.12% chlorhexidine gluconate (CHX) on salivary bacteria during scaling and root planing procedures (S&RP). Because blood and debris arising from S&RP could inactivate CHX and decrease its antimicrobial effect, patients were evaluated throughout their appointment. Forty subjects rinsed with either 15 ml of CHX rinse or control (sterile water) for 30 seconds, expectorated and immediately rinsed again for 30 seconds. Unstimulated saliva samples were obtained at baseline (immediately before rinsing), and at 1 minute, 30 minutes, and 60 minutes after baseline. All 30 and 60 minute samples contained visible blood and debris. Samples were immediately diluted in transport fluid containing a CHX-neutralizer and then plated on trypticase soy agar for enumeration of the total aerobic and facultative bacterial load. The dual rinses with 0.12% CHX immediately reduced the salivary bacterial load 97% and this reduction persisted for 60 minutes during S&RP. At 30 minutes and at 60 minutes aerobic bacteria were reduced 77% compared to control, and 96% compared to baseline. CHX was not inactivated by the high organic load (blood and debris) present during the procedure. Pre-procedural rinsing with CHX has a profound and sustained effect on the aerobic and facultative flora of the oral cavity, which may contribute to a variety of clinical benefits. Pre-procedural rinsing may also be of value in protecting patients and dental professionals during dental manipulations.

– In order to find out if it is possible to prevent caries and gingivitis by periodical use of chlorhexidine-fluoride mouthrinses with or without strontium, and to find out what effects they have on salivary mutans streptococci and lactobacilli counts, a total of 243 schoolchildren aged 11 yr with high DMFS scores were randomly divided into four groups. One group (C) served as a basic control. Subjects in the second group (GXF) rinsed their mouths twice a day every third week with a rinsing solution containing 0.05% chlorhexidine gluconate and 0.04% NaF. In the third group (CXFS) the rinsing solution contained 500 ppm Sr during the first and second year and 15 ppm during the last 6 months, in addition to chlorhexidine and fluoride. In the fourth group (CX) the solution contained only 0.05% chlorhexidine gluconate. All the rinsing solutions had pH 5.8 buffered with succinic acid-NaOH buffer. After 2 yr and 9 months, the mean DMFS (SD) increments in the C, GXF, GXFS, and GX groups were 3.8 (5.7), 2.5 (3.2), 3.5 (4.8), and 3.4 (5.5), respectively. The percentage of subjects with bleeding gingival units had decreased from initial to final values as follows: C, 81–38; GXF, 88–42; GXFS, 89–56; GX, 89–37. The number of lactobacilli and mutans streptococci in saliva remained virtually unchanged throughout the study. For caries increment and gingival bleeding, the differences between groups were not statistically significant. The chlorhexidine-fluoride combination tended to prevent caries, but the effect on gingival bleeding and salivary counts of mutans streptococci and lactobacilli was negligible.

Bacteriocins are bacteriocidal proteinaceous molecules produced by the Gram-positive bacteria not active against the produced strain. Many investigations have revealed that certain bacteria using antibacterial or the inhibitory substance inhibit some other bacteria. A study was conducted in a group of 60 children to ascertain whether any correlation exists between the proportion of salivary bacteria inhibiting and stimulating Streptococcus mutans and the oral health indices (DMFT, deft and Community Periodontal Index of Treatment Needs). A definite inverse correlation was observed between the percentage of salivary inhibiting S. mutans and untreated carious teeth (UCT).

The pH effects of urea metabolism were studied in washed salivary-sediment bacteria from subjects that had up to 10-fold variation in oral ureolytic activity, and in dispersed artificial-mouth plaques. Adequate evaluation required analysis of the [OH−] as well as the pH curve. An initial constant rate of pH-change, lasting until pH 7.8, was derived from the pH curve; this gave the best correlation (r = 0.95) with the ureolysis rate. From the [OH−]-curve, between pH 7.8 and 8.3 (approx.), a constant and maximal rate of change in [OH−] was determined. Although theoretically this was directly related to the rate of ammonia release, it was 10−2 to 10−3 times its value and correlated less well (r = 0.83) with ureolysis. Together with the initial and final pH, these two rates largely described urea-induced pH changes. After 12.5-fold dilution of the cells, changes in the pH curve were minor. Although the rate of ureolytic ammonia release was proportional to cell-protein concentration, the reduction in ureolytic activity was compensated by a corresponding reduction in cell pH-buffering. Consequently, in order to relate pH and [OH−] changes to ureolysis, it was necessary to control, or correct for, variations in the cell mass present. Buffering capacity in plaques was greater than in sediments. The 10-fold range in oral ureolytic activity by salivary bacteria gave a 10–20-fold range in base changes.

Nine commercial dental amalgams were tested for antibacterial properties in vitro. A bactericidal test on salivary bacteria, a growth inhibition test on Streptococcus mutans OMZ 176, and a time-dependent bactericidal test on Strep. mutans were used. All amalgams displayed some antibacterial properties. Dispersalloy and Revalloy were strongly antibacterial in all tests; ANA 2000 and Sybraloy killed Strep. mutans but were less potent in the salivary test and in the growth inhibition experiments. The copper amalgams, Neo-Silbrin and Cupromuc, were the most active in the salivary test but less inhibitory in the growth curve experiments. Spheraloy, Indiloy, and Amalcap showed intermediate activity in the salivary bactericidal test but were relatively weak in the growth inhibition studies. Analysis of Hg, Ag, and Cu in media from the growth inhibition studies showed release of Hg from the copper amalgams and, particularly, from Revalloy; Indiloy gave off Ag, whereas Neo-Silbrin, Cupromuc, Sybraloy, and ANA 2000 released more Cu than the other brands.

Comparison between two methods of counting shows that method B (the Lewis method) is more accurate and reproducible than method A (the Hadley method). A great advantage of Method B is the ease and rapidity of recognizing and counting the organisms. Variations in counts from organisms not L. acidophilus were found to be less than 1 per cent by either method and variations due to the individual workers are within the reported deviations of either method. The number of L. acidophilus is found to change at an unpredictable rate after collection of saliva samples, and the hydrogen-ion concentration also varies erratically and not in parallel with the numbers of L. acidophilus found.

A double blind crossover trial was carried out to assess the effect of povidone iodine on plaque accumulation in vivo and to measure the total salivary aerobes and anaerobes throughout the study. When compared to the placebo preparation, povidone iodine was without effect on plaque accumulation in all the subjects and there was a progressive increase in plaque throughout the 10-day periods. A 30 to 40 % overall reduction in aerobes and anaerobes occurred with the active preparation which was significant. There appears to be no indication for the use of povidone iodine as an adjunct to oral hygiene or in the treatment of chronic gingivitis.

A double-blind crossover trial was carried out to assess the effect of zinc citrate on plaque accumulation in vivo and to measure total salivary aerobes and anaerobes both during the trial and throughout the day following a single rinse. When compared to the placebo, zinc citrate significantly reduced the plaque accumulation in the subjects. However, the mean reduction was small and of questionable clinical importance. A progressive increase in plaque was observed throughout both active and placebo 7-day rinsing periods. There was no significant reduction in salivary bacterial counts either during the crossover study or during the day following a single rinse with zinc citrate.

Dentally-induced stress and relaxation-induced anxiety reduction have been correlated with salivary changes in dental patients in two recent studies. In two subsequent studies, test anxiety-induced stress and relaxation-induced anxiety reduction were correlated with salivary changes in dental students. In another study using the resazurin dye indicator, increased salivary bacterial levels were correlated with an increased dental caries incidence. As a result of these findings, it was decided to reinvestigate the effects of stress and relaxation on salivary changes and in addition to examine the effects of those conditions on salivary bacteria. The hypotheses under consideration were: (1) Salivary changes from stress to relaxation will be from opaque to translucent and from high to low protein levels; and (2) salivary bacteria will increase under the condition of stress and decrease under the condition of relaxation. The subjects were twelve dental students. Stress and relaxation were evaluated be...

Artificial-mouth plaques were cultured for 7 days from the saliva of two individuals, one with high and one with low salivary ureolytic activity. There was a 7.5-fold range in the resulting plaque ureolysis rates (per mg of protein), and the composition of the flora varied widely. The average rate of ureolysis of artificial plaque was similar to that in natural plaques but higher than in salivary sediment (after correction of sediment rates for the presence of 50 per cent non-bacterial protein). The average rate of ureolysis per ureolytic bacterium was 2.5 times higher in the artificial plaques than in saliva. Although the saliva inocula were from subjects with a 3-fold difference in salivary ureolysis rate, this difference was not reflected in the ureolytic activity of the artificial plaques. Neither was this difference evident in the ureolytic activity of the corresponding natural plaques. The established hypothesis that plaque ureolysis is derived mainly from an unidentified active segment of the total ureolytic flora was tested in the artificial plaques by analysis of variance to determine the contribution of the known ureolytic bacteria. Plaque ureolysis rates were almost entirely explained (r2 = 86 per cent) by the percentage of total detectable ureolytic bacteria in the plaque flora. The plaque bacteria giving strong ureolytic reactions on agar plates were all Gram-positive cocci and in 6 of the 9 plaques were streptococci only. Therefore, in artificial plaques the physiologically significant bacteria comprise a high proportion of the total ureolytic flora and are Gram-positive cocci, mainly streptococci.

Clean dry dental handpieces harbour few bacteria, but contamination of the handpiece lumen with salivary bacteria readily occurs in use. Wiping the outside of the handpiece with disinfectant does not eliminate the potential cross-infection risk. Water issuing from dental units is heavily infested with bacteria, some of oral origin, which presumably colonize the water piping of the units. Attempts to reduce this contamination with hydrogen peroxide were only partially successful.

IT IS WELL KNOWN that saliva contains large numbers of bacteria. These organisms have been thought to be dislodged from dental plaque or from gingival debris through the washing action of saliva. Consequently saliva has often been utilized as a substitute for dental plaque or gingival crevice debris in studies designed to elucidate the role of bacteria in either dental caries or periodontal disease. However, KRASSE (1954a) studied the distribution of Streptococcus salivarius in plaque, saliva, and on the tongue and cheeks. He found that Streptococcus salivarius comprised a large proportion of the facultative streptococci present in saliva and on the tongue, but this organism comprised only a small percentage of the facultative streptococci present in dental plaque. As a result of these and other studies, KRAUSE (1953,1954a,b)

The aim of this randomized, controlled clinical trial was to isolate and identify viable microorganisms in the saliva of study participants that continuously used a stannous and fluoride ion (F/Sn)-containing toothpaste and mouth rinse over a period of three years in comparison to a control group that used stannous ion free preparations (noF/Sn) over the same time period. Each group (F/Sn and noF/Sn) included 16 participants that used the respective oral hygiene products over a 36-month period. Stimulated saliva samples were collected at baseline (T0) and after 36 months (T1) from all participants for microbiological examination. The microbial composition of the samples was analyzed using culture technique, matrix-assisted laser desorption ionization–time of flight (MALDI–TOF) mass spectrometry, and 16S rDNA Polymerase Chain Reaction (PCR). There were only minor differences between both groups when comparing the absolute values of viable microbiota and bacterial composition. The treatment with F/Sn led to a slight decrease in disease-associated and a slight increase in health-associated bacteria. It was shown that the use of stannous ions had no negative effects on physiological oral microbiota even after prolonged use. In fact, a stabilizing effect of the oral hygiene products containing stannous ions on the health-associated oral microbiota could be expected.