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Background/purpose: There is a paucity of research focused on salivary bacteria analyzed through real-time polymerase chain reaction (qPCR) among adolescents. The current study determined the quantity of Streptococcus mutans (SM) and Lactobacillus (LB) in saliva obtained from Taiwanese adolescents and investigated the association between the oral bacteria and untreated dental caries. Materials and methods: This cross-sectional study recruited Taiwanese students aged 10−18. Saliva was collected using a Salivette kit and then analyzed through qPCR. The relative quantification values of SM and LB were coded based on mean fold ratios, with values > 2 coded as high and other values coded as low. Untreated dental caries was assessed through standard oral examinations. Univariate and multivariate logistic regression models were used to estimate the association between the levels of bacteria in the saliva of the study participants and the presence of untreated caries. Results: The study involved 421 adolescents. 56 (13.3%) had both SM and LB values of >2 and were coded as having high levels of bacteria, whereas the other 365 (86.7%) students were coded as having low levels. The multivariate logistic regression analysis revealed that adolescents who had high combined salivary SM and LB levels had an odds ratio of having untreated dental caries of 2.05 (95% CI = 1.09, 3.86, P = 0.027) compared with those who had low salivary SM and LB levels. Conclusion: The results of the present study indicate that salivary SM and LB levels are significantly associated with adolescents having untreated caries.

There is a paucity of research focused on salivary bacteria analyzed through real-time polymerase chain reaction (qPCR) among adolescents. The current study determined the quantity of Streptococcus mutans (SM) and Lactobacillus (LB) in saliva obtained from Taiwanese adolescents and investigated the association between the oral bacteria and untreated dental caries. This cross-sectional study recruited Taiwanese students aged 10−18. Saliva was collected using a Salivette kit and then analyzed through qPCR. The relative quantification values of SM and LB were coded based on mean fold ratios, with values > 2 coded as high and other values coded as low. Untreated dental caries was assessed through standard oral examinations. Univariate and multivariate logistic regression models were used to estimate the association between the levels of bacteria in the saliva of the study participants and the presence of untreated caries. The study involved 421 adolescents. 56 (13.3%) had both SM and LB values of >2 and were coded as having high levels of bacteria, whereas the other 365 (86.7%) students were coded as having low levels. The multivariate logistic regression analysis revealed that adolescents who had high combined salivary SM and LB levels had an odds ratio of having untreated dental caries of 2.05 (95% CI = 1.09, 3.86, P = 0.027) compared with those who had low salivary SM and LB levels. The results of the present study indicate that salivary SM and LB levels are significantly associated with adolescents having untreated caries. [ABSTRACT FROM AUTHOR]

Background/purpose: Perioperative oral care is widely provided to prevent postoperative pneumonia and surgical site infections in patients undergoing surgery under general anesthesia. However, there is a lack of clarity regarding the kind of oral care that should be provided for different patients. The purpose of this study was to clarify the factors that influence the increase in salivary bacterial counts before and after gastrointestinal surgery to identify patients with a particular need for oral care. Materials and methods: Twenty patients undergoing gastrointestinal surgery were examined before surgery for denture use, number of remaining teeth, regular dental care, Oral Hygiene Index-Simplfied tongue coating, tongue pressure, bite pressure, masticatory efficiency, and dry mouth. Saliva samples were collected before surgery, in the fasting period after surgery, and in the oral feeding period. Total bacterial counts were determined by real-time PCR, and factors associated with bacterial counts were investigated. Results: Patients with decreased oral functions, such as tongue pressure, bite pressure, and masticatory efficiency, tended to have higher salivary bacterial counts in the preoperative, fasting, and oral feeding periods. Regarding the pre- and postoperative changes, salivary bacterial counts increased in the fasting period compared to the pre-operative period and returned to preoperative values in the oral feeding period. Conclusion: Perioperative oral care is important for patients with reduced oral function because the number of bacteria in saliva tends to be higher in such patients. As the number of bacteria in saliva increases during the fasting period, oral care is important, and oral feeding should be restarted as soon as possible.

Perioperative oral care is widely provided to prevent postoperative pneumonia and surgical site infections in patients undergoing surgery under general anesthesia. However, there is a lack of clarity regarding the kind of oral care that should be provided for different patients. The purpose of this study was to clarify the factors that influence the increase in salivary bacterial counts before and after gastrointestinal surgery to identify patients with a particular need for oral care. Twenty patients undergoing gastrointestinal surgery were examined before surgery for denture use, number of remaining teeth, regular dental care, Oral Hygiene Index-Simplfied tongue coating, tongue pressure, bite pressure, masticatory efficiency, and dry mouth. Saliva samples were collected before surgery, in the fasting period after surgery, and in the oral feeding period. Total bacterial counts were determined by real-time PCR, and factors associated with bacterial counts were investigated. Patients with decreased oral functions, such as tongue pressure, bite pressure, and masticatory efficiency, tended to have higher salivary bacterial counts in the preoperative, fasting, and oral feeding periods. Regarding the pre- and postoperative changes, salivary bacterial counts increased in the fasting period compared to the pre-operative period and returned to preoperative values in the oral feeding period. Perioperative oral care is important for patients with reduced oral function because the number of bacteria in saliva tends to be higher in such patients. As the number of bacteria in saliva increases during the fasting period, oral care is important, and oral feeding should be restarted as soon as possible. [ABSTRACT FROM AUTHOR]

Abstract Background Pre-term birth, the leading cause of neonatal mortality, has been associated with maternal periodontal disease and the presence of oral pathogens in the placenta. However, the mechanisms that underpin this link are not known. This investigation aimed to identify the origins of placental microbiota and to interrogate the association between parturition complications and immune recognition of placental microbial motifs. Video Abstract Methods Saliva, plaque, serum, and placenta were collected during 130 full-term (FT), pre-term (PT), or pre-term complicated by pre-eclampsia (PTPE) deliveries and subjected to whole-genome shotgun sequencing. Real-time quantitative PCR was used to measure toll-like receptors (TLR) 1–10 expression in placental samples. Source tracking was employed to trace the origins of the placental microbiota. Results We discovered 10,007 functionally annotated genes representing 420 taxa in the placenta that could not be attributed to contamination. Placental microbial composition was the biggest discriminator of pregnancy complications, outweighing hypertension, BMI, smoking, and maternal age. A machine-learning algorithm trained on this microbial dataset predicted PTPE and PT with error rates of 4.05% and 8.6% (taxonomy) and 6.21% and 7.38% (function). Logistic regression revealed 32% higher odds of parturition complication (95% CI 2.8%, 81%) for every IQR increase in the Shannon diversity index after adjusting for maternal smoking status, maternal age, and gravida. We also discovered distinct expression patterns of TLRs that detect RNA- and DNA-containing antigens in the three groups, with significant upregulation of TLR9, and concomitant downregulation of TLR7 in PTPE and PT groups, and dense correlation networks between microbial genes and these TLRs. 70–82% of placental microbiota were traced to serum and thence to the salivary and subgingival microbiomes. The oral and serum microbiomes of PTPE and PT groups displayed significant enrichment of genes encoding iron transport, exosome, adhesion, quorum sensing, lipopolysaccharide, biofilm, and steroid degradation. Conclusions Within the limits of cross-sectional analysis, we find evidence to suggest that oral bacteria might translocate to the placenta via serum and trigger immune signaling pathways capable of inducing placental vascular pathology. This might explain, in part, the higher incidence of obstetric syndromes in women with periodontal disease.

Background: Pre-term birth, the leading cause of neonatal mortality, has been associated with maternal periodontal disease and the presence of oral pathogens in the placenta. However, the mechanisms that underpin this link are not known. This investigation aimed to identify the origins of placental microbiota and to interrogate the association between parturition complications and immune recognition of placental microbial motifs. 61FbVQciH1C2BbwKYgvy28 Video Abstract Methods: Saliva, plaque, serum, and placenta were collected during 130 full-term (FT), pre-term (PT), or pre-term complicated by pre-eclampsia (PTPE) deliveries and subjected to whole-genome shotgun sequencing. Real-time quantitative PCR was used to measure toll-like receptors (TLR) 1–10 expression in placental samples. Source tracking was employed to trace the origins of the placental microbiota. Results: We discovered 10,007 functionally annotated genes representing 420 taxa in the placenta that could not be attributed to contamination. Placental microbial composition was the biggest discriminator of pregnancy complications, outweighing hypertension, BMI, smoking, and maternal age. A machine-learning algorithm trained on this microbial dataset predicted PTPE and PT with error rates of 4.05% and 8.6% (taxonomy) and 6.21% and 7.38% (function). Logistic regression revealed 32% higher odds of parturition complication (95% CI 2.8%, 81%) for every IQR increase in the Shannon diversity index after adjusting for maternal smoking status, maternal age, and gravida. We also discovered distinct expression patterns of TLRs that detect RNA- and DNA-containing antigens in the three groups, with significant upregulation of TLR9, and concomitant downregulation of TLR7 in PTPE and PT groups, and dense correlation networks between microbial genes and these TLRs. 70–82% of placental microbiota were traced to serum and thence to the salivary and subgingival microbiomes. The oral and serum microbiomes of PTPE and PT groups displayed significant enrichment of genes encoding iron transport, exosome, adhesion, quorum sensing, lipopolysaccharide, biofilm, and steroid degradation. Conclusions: Within the limits of cross-sectional analysis, we find evidence to suggest that oral bacteria might translocate to the placenta via serum and trigger immune signaling pathways capable of inducing placental vascular pathology. This might explain, in part, the higher incidence of obstetric syndromes in women with periodontal disease. [ABSTRACT FROM AUTHOR]

In the present research, the MALDI-TOF MS technique was applied as a tool to rapidly identify the salivary microbiome. In this fact, it has been monitored the changes occurred in molecular profiles under different antibiotic therapy. Significant changes in the composition of the salivary microbiota were noticed not only in relation to the non antibiotic (non-AT) and antibiotic treatment (AT) groups, but also to the used media, the antibiotic therapy and co-existed microbiota. Each antibiotic generates specific changes in molecular profiles. The highest number of bacterial species was isolated in the universal culture medium (72%) followed by the selective medium (48% and 38%). In the case of non-AT patients, the prevalence of Streptococcus salivarius (25%), Streptococcus vestibularis (19%), Streptococcus oralis (13%), and Staphylococcus aureus (6%) was identified while in the case of AT, Streptococcus salivarius (11%), Streptococcus parasanguinis (11%), Staphylococcus epidermidis (12%), Enterococcus faecalis (9%), Staphylococcus hominis (8%), and Candida albicans (6%) were identified. Notable to specified that the Candida albicans was noticed only in AT samples, indicating a negative impact on the antibiotic therapy. The accuracy of the MALDI-TOF MS technique was performed by the 16S rRNA gene sequencing analysis—as a reference method. Conclusively, such an approach highlighted in the present study can help in developing the methods enabling a faster diagnosis of disease changes at the cellular level before clinical changes occur. Once the MALDI tool allows for the distinguishing of the microbiota of non-AT and AT, it may enable to monitor the diseases treatment and develop a treatment regimen for individual patients in relation to each antibiotic. Key points: The salivary microbiota of antibiotic-treated patients was more bacteria variety MALDI-TOF MS is a promising tool for recording of reproducible molecular profiles Our data can allow to monitor the treatment of bacterial diseases for patients [ABSTRACT FROM AUTHOR]

The aim is to explore the predictive value of salivary bacteria for the presence of esophageal squamous cell carcinoma (ESCC). Saliva samples were obtained from 178 patients with ESCC and 101 healthy controls, and allocated to screening and verification cohorts, respectively. In the screening phase, after saliva DNA was extracted, 16S rRNA V4 regions of salivary bacteria were amplified by polymerase chain reaction (PCR) with high-throughput sequencing. Highly expressed target bacteria were screened by Operational Taxonomic Units clustering, species annotation and microbial diversity assessment. In the verification phase, the expression levels of target bacteria identified in the screening phase were verified by absolute quantitative PCR (Q-PCR). Receiver operating characteristic (ROC) curves were plotted to investigate the predictive value of target salivary bacteria. LEfSe analysis revealed higher proportions of Fusobacterium, Streptococcus and Porphyromonas, and Q-PCR assay showed significantly higher numbers of Streptococcus salivarius, Fusobacterium nucleatum and Porphyromonas gingivalis in patients with ESCC, when compared with healthy controls (all P

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. [ABSTRACT FROM AUTHOR]

BackgroundImbalance of oral salivary microbiota has been linked to the pathogenesis of a variety of systemic diseases, and oral bacterial species have been shown to be useful biomarkers for systemic diseases.This study aimed to characterize the alterations of oral microbiota in patients with esophageal squamous cell carcinoma (ESCC) and to evaluate the diagnostic performance of oral microbial biomarkers for ESCC.MethodsThe relative abundance of flora in saliva samples was analyzed by 16S rDNA sequencing, and differences in the species present in samples from ESCC patients and healthy controls (HCs) were identified by analyzing species diversity and performing LEfSe analysis. Receiver operating characteristic (ROC) curve analysis was applied to evaluate the diagnostic performance of the characteristic bacteria individually and in combination.ResultsDifferences in bacterial diversity indexes were observed for the saliva of ESCC patients versus HCs (P0.05). LEfSe analysis showed that Leptotrichia, Porphyromonas (Pg), Streptococcus, Rothia, Lactobacillus and Peptostreptococcus were more abundant in ESCC patient saliva than in HC saliva, whereas Haemophilus, Alloprevotella (All), Prevotella_7, Prevotella (Pre), Prevotella_6, Pasteurellaceae and Pasteurellales were significantly less abundant in ESCC patient saliva (P

Abstract Background Oral functions are known to decline with aging. However, there is limited evidence that supports the relationship between oral health and frailty. This study aimed to clarify the relationship between oral hygiene conditions, measured by remaining teeth and mucosa, and frailty among elderly people dwelling in a Japanese rural community. Methods We surveyed self-reliant elderly individuals aged ≥65 years who were dwelling in the Sasayama-Tamba area of Hyogo, Japan. Frailty was evaluated according to the total score of the Kihon Checklist (KCL). Based on the KCL score, elderly participants were divided into three groups: robust, pre-frail, and frail. The items measured to evaluate oral environment included the number of remaining teeth, denture usage condition, oral hygiene status, dry mouth condition, and salivary bacterial count. For statistical analysis, Fisher’s exact test, one-way analysis of variance, and multiple comparison technique were used. Results Of 308 elderly participants, 203 (65.9%), 85 (27.6%), and 20 (6.5%) belonged to the robust, pre-frail, and frail groups, respectively. The proportion of participants who were judged to have poor hygiene was significantly higher in the frail group than in the other two groups. The bacterial count was significantly smaller in the frail group than in the robust group, and the frail group had fewer number of remaining teeth than the other two groups, suggesting that the number of remaining teeth may be associated with bacterial count. Conclusion In elderly adults, physical frailty may affect the oral hygiene status and condition of the remaining teeth.

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. [ABSTRACT FROM AUTHOR]

Considering the shortcomings related to antibiotics usage, the introduction of other bacteriostatic and bactericidal agents that present synergetic effects or standalone properties is urgently needed. AgNO 3 is an important bactericidal agent, which imparts various functions on bacteria dependent on its concentration. Therefore, an understanding of its mechanisms of action in infinitesimal concentrations plays an important role which can ultimately lead to AgNO 3 involvement in the pharmaceutical industry. The monitoring of VOC (volatile organic compound) profiles emitted by bacteria is a simple method to assess changes occurring in bacterial metabolism. In this study, VOCs of Hafnia alvei , Pseudomonas luteola and Staphylococcus warneri cultures were analyzed both in the absence and in the presence of three concentrations of AgNO 3. Headspace solid-phase microextraction gas chromatography/mass spectrometry (HS-SPME-GC/MS) was employed for extraction and analysis. After supplementation with AgNO 3 , changes in the emitted fingerprints were investigated. Odorants associated with mouth-related and systemic diseases, like dimethyl trisulfide, indole (halitosis) and 2-hexanone (celiac disease), were also affected by addition of AgNO 3. Statistical tests proved discrimination between obtained profiles with more that 90% variability. Moreover, physiological states of bacteria after dosage with various concentration of stressing agent were investigated and explained by the mechanisms of action. Image 1 • Statistical approaches pointed out differences between metabolites distribution from bacterial samples. • Silver nitrate dosed with three different concentrations caused significant changes in VOC profiles from tested bacteria. • Volatiles from obtained profiles in native and treated strains originated from biological pathways occurred in bacteria. [ABSTRACT FROM AUTHOR]

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.

Context: This study evaluates the antimicrobial efficacy of commercially available chlorhexidine (CHX) mouthrinses of different concentrations. Aims: To evaluate and compare the antimicrobial efficacy of commercially available CHX mouthrinses of different concentrations (0.2%, 0.12%, and 0.1%) against specific standard strains of oral microflora at full strength (FS) and 1:1 dilution at 24 h. Settings and Design: Ten commercially available 0.2% (Rexidine, Hexidine, Smilehex, Chlorhex, Hexidale, Hex, Everfresh, and Gargwell), 0.12% (Periogard), and 0.1% (Eludril) CHX mouthrinses were selected to evaluate the efficacy against specific oral microflora using agar well diffusion Method. Materials and Methods: The standard strains of Streptococcus mutans American Type Culture Collection (ATCC 21293), Streptococcus sanguis Microbial Type Culture Collection (MTCC 442), Actinomyces viscosus (ATCC 3268), Staphylococcus aureus (ATCC 25923), Streptococcus pyogenes (MTCC 442), and Candida albicans (MTCC 183) were selected. The antimicrobial efficacy was calculated by measuring mean inhibitory zones formed on agar media. Statistical Analysis Used: Independent t-test, one-way ANOVA, Kruskal-Wallis tests, and Tukey′s Post hoc analysis were used. Results: Among 0.2% of CHX mouthrinses at FS and 1:1 dilution, hexidine was effective against most of the microorganisms except with S. pyogenes and C. albicans, where Hex and Hexidale were effective, respectively. When the concentration of 0.1% and 0.12% CHX was considered, Eludril was more effective at FS against all except with S. aureus and S. pyogenes which were more sensitive to Periogard at both FS and 1:1 dilution. Conclusions: 0.12% and 0.1% of CHX mouthrinses showed comparable efficacy with 0.2% CHX mouthrinses irrespective of their formulations.

Context: This study evaluates the antimicrobial efficacy of commercially available chlorhexidine (CHX) mouthrinses of different concentrations.Aims: To evaluate and compare the antimicrobial efficacy of commercially available CHX mouthrinses of different concentrations (0.2%, 0.12%, and 0.1%) against specific standard strains of oral microflora at full strength (FS) and 1:1 dilution at 24 h.Settings and Design: Ten commercially available 0.2% (Rexidine, Hexidine, Smilehex, Chlorhex, Hexidale, Hex, Everfresh, and Gargwell), 0.12% (Periogard), and 0.1% (Eludril) CHX mouthrinses were selected to evaluate the efficacy against specific oral microflora using agar well diffusion Method.Materials and Methods: The standard strains of Streptococcus mutans American Type Culture Collection (ATCC 21293), Streptococcus sanguis Microbial Type Culture Collection (MTCC 442), Actinomyces viscosus (ATCC 3268), Staphylococcus aureus (ATCC 25923), Streptococcus pyogenes (MTCC 442), and Candida albicans (MTCC 183) were selected. The antimicrobial efficacy was calculated by measuring mean inhibitory zones formed on agar media.Statistical Analysis Used: Independent t-test, one-way ANOVA, Kruskal-Wallis tests, and Tukey's Post hoc analysis were used.Results: Among 0.2% of CHX mouthrinses at FS and 1:1 dilution, hexidine was effective against most of the microorganisms except with S. pyogenes and C. albicans, where Hex and Hexidale were effective, respectively. When the concentration of 0.1% and 0.12% CHX was considered, Eludril was more effective at FS against all except with S. aureus and S. pyogenes which were more sensitive to Periogard at both FS and 1:1 dilution.Conclusions: 0.12% and 0.1% of CHX mouthrinses showed comparable efficacy with 0.2% CHX mouthrinses irrespective of their formulations. [ABSTRACT FROM AUTHOR]

We report a clinical trial of the effects of test tablets containing bovine lactoferrin and lactoperoxidase on oral malodor and salivary bacteria. Fifteen subjects with volatile sulfur compounds (VSCs) in mouth air above the olfactory threshold (HS >1.5 or CHSH >0.5 ng/10 ml) as detected by gas chromatography were enrolled in the trial. Either a test or a placebo tablet was ingested twice at 1-h intervals in two crossover phases. Mouth air was monitored for VSC levels at the baseline before ingestion of a tablet, 10 min after the first ingestion, 1 h (just before the second ingestion), and 2 h after the first ingestion. Whole saliva was analyzed at the baseline and at 2 h for bacterial numbers. At 10 min, the level of CHSH was significantly lower in the test group (median [interquartile range] = 0.28 [0.00-0.68] ng/10 ml) compared to that in the placebo group (0.73 [0.47-1.00] ng/10 ml; P = 0.011). The median concentration of CHSH in the test group was below the olfactory threshold after 10 min until 2 h, whereas the level in the placebo group was above the threshold during the experimental period. No difference in the numbers of salivary bacteria was detected by culturing or quantitative PCR, but terminal restriction fragment length polymorphism detected one fragment with a significantly lower copy number at 2 h in the test group (mean ± standard error, 4.89 ± 0.11 log copies/10 µl) compared to that in the placebo group (5.38 ± 0.15 log copies/10 µl; P = 0.033). These results indicate a suppressive effect of the test composition on oral malodor and suggest an influence on oral bacteria. [ABSTRACT FROM AUTHOR]

The article presents the results of a study which investigated the effect of cetylpyridinium chloride and a synthetic antimicrobial peptide, delivered in a chewing gum base, on the growth of oral biofilms. Details of the experimental protocol are provided. It was found that this method was an effective means of killing biofilm cells, and destroying the viability and structural integrity of dental plaque biofilms. The advantages of delivering the peptide in a chewing gum matrix are noted, and the varying degrees of bactericidal effect produced by varying dosages are delineated.

Oral biofilms are mixed-species microbial communities, and their uncontrolled outgrowth can express as oral diseases. Antimicrobial peptides represent alternative classes of antimicrobials that exhibit selectivity for prokaryotes. We wanted to test the effect of a synthetic decapeptide antimicrobial, KSL, on the development of oral biofilms formed by isolated human salivary bacteria. We used differential interference contrast microscopy, coupled with a dual-flow cell system, to determine the effect of KSL on oral biofilm development. We used reductions of viable counts and confocal microscopy to assess the bactericidal activity of KSL on mature oral biofilms. KSL effectively blocked biofilm development. A significant effect on the viability of mature biofilms was observed when KSL was used in the presence of a surface-active agent, or after biofilms were mechanically disrupted. This study shows that KSL may be a useful adjunct for conventional oral hygiene to prevent plaque-mediated dental diseases. [ABSTRACT FROM AUTHOR]

Roldán S, Herrera D, Santa-Cruz I, O'Connor A, González I, Sanz M: Comparative effects of different chlorhexidine mouth-rinse formulations on volatile sulphur compounds and salivary bacterial counts. J Clin Periodontol 2004; 31: 1128–1134. doi: 10.1111/j.1600-051X.2004.00621.x.© Blackwell Munksgaard, 2004.To compare five different commercial mouth rinses with chlorhexidine (CHX) with respect to their anti-halitosis effect and anti-microbial activity on salivary bacterial counts, following a standardised research protocol. And secondly, to validate the study model proposed in the evaluation of patients suffering from halitosis.Ten volunteers, with a healthy oral status, were enrolled in a double-blind, cross-over design, using sterile saline as negative control and five CHX-containing mouth rinses: 0.12% CHX alone (CHX+NO), plus alcohol (CHX+ALC), plus 0.05% cetylpiridinium chloride (CHX+CPC), plus sodium fluoride (CHX+NaF), and 0.05% CHX plus 0.05% CPC, plus 0.14% zinc lactate (CHX+Zn). The levels of whole-mouth volatile sulphur compounds (VSCs) were measured by means of a sulphide monitor at baseline, 1 and 5 h after rinsing with the assigned product. Baseline measurements also included an organoleptic assessment and the recording of the tongue-coating index. Aerobic and anaerobic salivary bacterial counts were also obtained by collecting unstimulated saliva samples at the same evaluation times, and processed by culturing techniques. Analysis of variance was used to evaluate whether significant differences existed among groups, at each evaluation point, or in changes between evaluations.No significant differences were detected at baseline, with VSC levels ranging between 190 and 227 parts per billion (p.p.b.) After rinsing, VSC levels were reduced with all products (except saline), after 1 h. Significant differences at 1 h were detected (p=0.04), corresponding to a lower amount of p.p.b. (109) in (CHX+Zn) as compared with the other groups (except CHX+NO). At 5 h, VSC levels were lower for CHX+CPC and CHX+Zn (155 and 169, respectively), while the other groups showed levels higher than 220 p.p.b. With respect to aerobic salivary bacterial counts, CHX+CPC demonstrated the lowest percentage of survival (6% after 1 h and 18% after 5 h). For anaerobic bacterial counts, again CHX+CPC demonstrated the lowest percentage of survival (10% at 1 h and 23% at 5 h), together with CHX+ALC (18% of survival at 5 h). However, salivary counts and VSCs were only significantly correlated at baseline, but not after treatment.Important differences can be expected from different CHX formulations, in relation to both their anti-halitosis effect and anti-microbial activity in saliva. Formulations that combine CHX and CPC achieved the best results, and a formulation combining CHX with NaF resulted in the poorest. [ABSTRACT FROM AUTHOR]

Sreenivasan PK, Gittins E. Effects of low dose chlorhexidine mouthrinses on oral bacteria and salivary microflora including those producing hydrogen sulfide. Oral Microbiol Immunol 2004: 19: 309–313© Blackwell Munksgaard, 2004. Clinical studies have demonstrated the considerable effects of chlorhexidine on dental plaque and oral microbiota as well as improvements in indices of oral health. This investigation examined the efficacy of lower concentrations of chlorhexidine. Mouthrinses with 0.03%, 0.06%, 0.12% chlorhexidine and a control rinse without chlorhexidine were examined. Alamar blue, an oxidation-reduction dye with fluorescent end-points proportional to bacterial viability, was used to determine bacterial viability. Further clinical studies examined the effects of these rinses on salivary bacteria and on bacteria producing hydrogen sulfide (H2S) and implicated in halitosis. In laboratory tests, a significant dose-dependent effect was observed with Actinomyces viscosus as a model system using the Alamar blue procedure (P < 0.05). Clinical studies examined the effects 1.5 h and 3 h post-treatment on salivary bacteria and bacteria producing H2S. The first study compared the control rinse with the 0.03% and 0.06% chlorhexidine rinses; a second study compared the effects of the control rinse and the 0.06% and 0.12% chlorhexidine mouthrinses. In both studies, chlorhexidine rinses demonstrated significant dose-dependent effects post-treatment on salivary bacteria vs. the control rinse (P < 0.05). Significant decreases in H2S-producing bacteria were noted with these chlorhexidine rinses vs. the control rinse (P < 0.05). The results highlight the dose-dependent relationships noted in laboratory and clinical tests which have potential implications for the use of lower doses of chlorhexidine to inhibit oral bacteria, including those implicated in halitosis. [ABSTRACT FROM AUTHOR]

Abstract Aim: To evaluate the in vitro and in vivo antimicrobial activity of four commercial 0.12% chlorhexidine mouthrinses. Material and methods: The in vitro antimicrobial activity test consisted in a modified contact test where 20 selected bacterial species were tested during 1 min with each test product. After the contact, the inoculum was cultured, and the results were expressed in terms of survival/resistance and the percentage of survival as compared to a saline control. The in vivo test consisted of a double-blind, randomized, crossover salivary bacterial counts study. 10 volunteers rinsed during 1 min with each tested product. Saliva samples were obtained before rinsing, and after 5 min, and 1, 3, 5 and 7 h. These samples were cultured both aerobically and anaerobically. Percentages of survival, in regard to baseline, were calculated for each time point. Comparisons among products were tested using anova and selected paired t -test. Results: The in vitro contact test showed no survival in any tested species with CHX+CPC, while three species (Lactobacillus casei, Streptococcus mitis and Peptostreptococcus micros ) were resistant to the other three products. CHX and CHX+NaF demonstrated additional resistant species (three and four species, respectively). The in vivo salivary bacterial counts test showed higher reductions of CHX+CPC and CHX+ALC in aerobic and anaerobic bacteria, lasting for 5 h. Significant differences were detected at multiple time points, when these two products were compared both with the control and the other tested products. Conclusion: Important differences in activity, among 0.12% CHX products, were detected by both in vitro and in vivo tests. The formulation with alcohol was more active than those without alcohol, excepting the formulation with CHX+CPC, in which the reformulation and addition of CPC not only compensate but rather increase the antimicrobial activity. [ABSTRACT FROM AUTHOR]

This study is aimed at determining whether a commercially available varnish, containing 40% chlorhexidine, is able to reduce the numbers of mutans streptococci and lactobacilli in saliva, in a moderately caries-active population in Surinam. 238 children, ages 13-14 years, were selected from different schools in Paramaribo, Surinam. From these children, total dental status was recorded and saliva samples were taken. At baseline and every 6 months, a 40% chlorhexidine varnish (EC40®) was applied. The control group received a neutral gel that did not contain chlorhexidine. The numbers of salivary mutans streptococci and lactobacilli were calculated by standard methods, and the caries status was recorded every 12 months. The study lasted 30 months. The results indicate that chlorhexidine varnish did not decrease the numbers of cariogenic bacteria, nor did it decrease caries progression. Moreover, in this population with a low dental health care, children with lactobacilli present in the saliva above our detection level, the chlorhexidine varnish even tended to increase caries progression, possibly due to selection of aciduric and acidogenic oral bacterial species. We therefore conclude that 40% chlorhexidine varnish is not likely to decrease caries in children in a high-treatment-need population without treatment of the sources of infection. [ABSTRACT FROM AUTHOR]

Acidified sodium chlorite (ASC) is recognised as a highly potent, broad spectrum antimicrobial system that has been successfully developed for uses in veterinary, food processing and medical device fields. The current studies aimed to investigate the persistence of antimicrobial action and plaque inhibitory properties of 3 ASC mouthrinses by comparison with positive control, chlorhexidine 0.12%, and placebo control, water, rinses. Both studies were randomised, double-blind, cross-over 5-cell designs balanced for carryover. The Ist study involved 15 healthy subjects who immediately before and at 30, 60, 180, 300 and 420 min after rinsing provided 2 ml saliva samples. The samples were immediately processed for total anaerobic bacterial counts recorded after 96 h incubation. Washout periods were a minimum of 3 days. The second study involved 20 healthy subjects who on day 1 of each study were rendered plaque free, suspended normal oral hygiene methods and commenced rinsing twice daily with the allocated rinse. On day 5, plaque was scored by index and area after disclosing with erythrosin. Washout periods were 2 1/2 days. The 3 ASC and chlorhexidine rinses produced similar reductions in salivary bacterial counts which remained significantly below the placebo control to 7 h. There were no significant differences between ASC and chlorhexidine rinses except at 30 and 60 min when significantly greater reductions were produced by 2 ASC rinses compared to the chlorhexidine rinse. Plaque indices and areas were considerably and significantly lower with the ASC and chlorhexidine rinses compared to the placebo rinse. There were no significant differences between plaque scores for the 3 ASC rinses and the chlorhexidine rinse, although for 2 ASC rinses plaque scores were lower than for the chlorhexidine rinse. The results indicate that the 3 ASC rinses have equivalent plaque inhibitory action to chlorhexidine as a rinse. Similar to chlorhexidine, the plaque inhibitory action of the rinses appears to be derived from a persistence of antimicrobial action in the mouth. [ABSTRACT FROM AUTHOR]

There has been a resurgence of interest in stannous fluoride (SF) products in particular to provide oral hygiene and gingival health benefits. The aim of this study was to assess the persistence of antimicrobial action of a number of SF formulations in the mouth and relate these to plaque inhibitory activity. The formulations were 2 SF toothpastes (SF1, SF2), 2 SF plus stannous pyrophosphate toothpastes (SFSP1, SFSP2), a SF gel (G), a NaF toothpaste (C) and saline (S) as control. Both studies involve 2 different groups of 21 healthy dentate volunteers. The studies were single, blind, randomised, crossover designs balanced for residual effects, with a minimum 2 ½ day washout period. Salivary bacterial counts were determined before and to 7 h after a single rinse with the formulations. Plaque regrowth from a zero baseline (day 1) was measured by index and area on day 5, after 2× daily rinsing with slurries of the formulations or saline. For bacterial counts, highly significant treatment differences were found. Bacterial counts were variably reduced by all treatments to 30 min then showed a variable rate of return towards baseline. All test agents were significantly better than S at some timepoints. The order for greatest persistence of action downwards was; (1) SFSP2; (2) SFSP1, G, and SF1; (3) SF2; (4) C; (5) S. Highly significant differences in plaque regrowth between treatments were found with similar mean ordering of efficacy as for salivary bacterial counts from most effective downwards namely; (1) SFSP1 and SFSP2; (2) SF1; (3) SF2; G and C; (4) S. The results were consistent with a parallel study measuring tea staining in vitro, whereby formulations causing the most staining produced the greatest persistence of action and plaque inhibitory activity. This suggests the availability of stannous ions was important for the clinical effects. It is concluded that stannous ions can enhance the plaque inhibitory action of toothpaste via a persistent antimicrobial action. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the value of screening studies to assess the efficacy of antiseptic mouthrinse products relative to proven products. The products tested were 6 antiseptic mouthrinses available in France. 4 contained chlorhexidine (Eludril, Hibident, Parodex and Prexidine) with Hibident considered the positive control. 1 product contained cetylpyridinium chloride (Alodont) and 1 hexetidine (Hextril). Saline was used as the negative control. The 1st study assessed the persistence of action of the products by recording salivary bacterial counts before and up to 7 h after single rinses. The 2nd study measured the inhibition of plaque regrowth, from a zero baseline, in the absence of tooth-brushing over a 4-day period. Both studies used blind randomised crossover designs balanced for residual effects. Salivary bacterial count reductions with time were highly significantly different bctween products. Compared to saline, decrements were only significantly greater for Parodex to 5 h and Hibident and Prexidine to 7 h; There were no significant differences between the latter three chlorhexidine rinses except at 3 h, when decrements were significantly less with Parodex. Despite a mean trend in favour, Alodont, Eludril and Hextril were not significantly different from saline. Plaque inhibition by area and index was highly significantly different between products. Hibident, Parodex and Prexidine showed similar plaque inhibition and were significantly more effective than all other rinses. Eludril and Hextril were significantly more effective than saline but Alodont was not. Taken with the associated study in vitro and published reports on the same or similar products, it is apparent that efficacy of a product cannot be assumed merely because it contains a known active plaque inhibitor. Studies in vitro can provide supportive evidence but should not stand alone. Clinical investigations similar to these should be a minimum requirement for any oral hygiene product before claims of efficacy comparable to established products arc made. [ABSTRACT FROM AUTHOR]

A number of commonly used toothpaste ingredients, such as detergents, possess not inconsiderable antimicrobial activity. Additionally, specific ingredients including triclosan are now added to toothpastes to enhance such activity and to improve plaque inhibition. To date, there have been few studies of the antimicrobial properties in vivo of individual toothpaste ingredients. Most investigations have evaluated the whole toothpaste product. Persistence of antimicrobial action in vivo has been shown to relate to potential plaque inhibitory action. The aim of this study was to compare the magnitude and duration of salivary bacterial count reductions produced by a single rinse of 0.2% triclosan, 1% sodium lauryl sulphate (SLS) and 0.2% chlorhexidine mouthwashes. 16 volunteers took part in a single-blind latin-square randomised crossover designed study with balanced residual effects. Before and for time periods up to 420 mm following rinsing with the allocated mouthwashes, saliva samples were obtained and processed for total anaerobic counts. With the exception of the saline control rinse, the 3 test solutions produced considerable reductions in bacterial counts which remained significant to 3 h for triclosan and 7 h for SLS and chlorhexidine. However, at most time periods after baseline, the effects of chlorhexidine were significantly greater than triclosan and SLS. Overall, SLS had significantly greater effects than triclosan. Incremental values from 30 min post rinsing were always positive for SLS and triclosan, indicating bacterial recovery, whereas these values were negative for chlorhexidine. The results indicate that triclosan and: SLS provide some persistance of antimicrobial: activity in the oral cavity when used at relatively high dose compared to a toothpaste vehicle. [ABSTRACT FROM AUTHOR]

A previous study demonstrated that triclosan and stannous fluoride containing oral hygiene products reduced plaque regrowth compared to saline but were not more effective than a conventional commercial fluoride/anionic detergent toothpaste. To further understand these results, this study measured the persistance of antimicrobial activity of the same products by recording the duration of salivary bacterial count reductions following a single exposure to each product. Comparison was also made with a chlorhexidine rinse as the positive control. From a panel of 16 volunteers, in an 8-cell randomised cross-over designed study, salivary bacterial counts were recorded at baseline and to 420 mm. All test and control products were significantly more effective than saline and significantly less effective than chlorhexidine at suppressing bacterial counts. Unlike chlorhexidine, evidence of bacterial recovery was apparent after the 30-min sampling time. There were essentially no significant differences between the test and control products, although the stannous fluoride toothpaste performed marginally better than other products. The findings are consistent with the plaque regrowth results previously obtained and again demonstrate to date that it is difficult to surpass the antimicrobial and plaque inhibitory properties of conventional commercially available toothpastes by the addition of antimicrobial agents such as triclosan and metal salts. [ABSTRACT FROM AUTHOR]

This study measured the incidence of dental caries for one year and identified factors associated with the risk of caries in a sample of 156 elderly subjects. The subjects were examined at baseline and after one year to record the number of missing, filled and decayed teeth, to measure oral hygiene and flow of saliva, and to estimate the numbers of Streptococcus mutans and Lactobacilli cultured from samples of saliva. All subjects were interviewed on both occasions for information on their use of medications and dental services and on their ingestion of sugar. At baseline the elders had a mean of 19 natural teeth with 5 decayed surfaces (DS), 38 filled surfaces and a mean Plaque Index (PI) of 1. The independent group, on average, had more teeth and fillings but a lower PI and less caries. At the end of the year more than two-thirds (71%) of the 98 institutionalised subjects and over half (59%) of the 58 independent subjects had at least one new decayed/filled surface (DFS). The mean net DFS increment per subject was 4.6 and 2.0 respectively. Regression analyses on multivariate models identified caries at baseline, residence in long term care facilities, high numbers of Lactobacilli, poor oral hygiene and frequent sugar consumption as the variables contributing most significantly to the risk of caries in old age. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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.