Interpretación errónea del concepto de entropía

Background Cetylpyridinium chloride (CPC) and sodium fluoride augment oral hygiene by inactivating bacteria and inhibiting enamel demineralisation, respectively. However, there are few reports in the literature documenting the antibacterial efficacy of their combined use in mouthrinses. We have used six experimental systems to compare the antibacterial effects of mouthrinses containing 0.075 % CPC (test rinse, TR) or 0.075 % CPC with sodium fluoride (test fluoride rinse, TFR). Results Effects against planktonic bacteria were determined using viable counting (for Streptococcus mutans and salivary bacteria), a redox dye (for Actinomyces viscosus and salivary bacteria) and viable counting (for ex vivo oral rinses). Effects against saliva-derived biofilms were quantified using confocal microscopy and differential viable counting. Inhibition of biofilm formation was evaluated by pre-treating hydroxyapatite coupons with mouthrinses prior to inoculation. Otherwise-identical controls without CPC (control rinse and control fluoride rinse, CR and CFR, respectively), were included throughout. Compared to the controls, TFR and TR demonstrated significant antimicrobial effects in the redox assays, by viable counts (>3 log reductions) and in oral rinse samples (>1.25 log reductions, p 3 log difference, p < 0.05). Overall, there were no consistent differences in the activities of TR and TFR. Conclusions Sodium fluoride did not influence the antibacterial and anti-biofilm potency of CPC-containing formulations, supporting the combined use of CPC and sodium fluoride in mouthrinses to control oral bacteria and protect tooth enamel

Simultaneous assessment of acidogenesis-mitigation and specific bacterial growth-inhibition by dentifrices

Dentifrices can augment oral hygiene by inactivating bacteria and at sub-lethal concentrations may affect bacterial metabolism, potentially inhibiting acidogenesis, the main cause of caries. Reported herein is the development of a rapid method to simultaneously measure group-specific bactericidal and acidogenesis-mitigation effects of dentifrices on oral bacteria. Saliva was incubated aerobically and anaerobically in Tryptone Soya Broth, Wilkins-Chalgren Broth with mucin, or artificial saliva and was exposed to dentifrices containing triclosan/copolymer (TD); sodium fluoride (FD); stannous fluoride and zinc lactate (SFD1); or stannous fluoride, zinc lactate and stannous chloride (SFD2). Minimum inhibitory concentrations (MIC) were determined turbidometrically whilst group-specific minimum bactericidal concentrations (MBC) were assessed using growth media and conditions selective for total aerobes, total anaerobes, streptococci and Gram-negative anaerobes. Minimum acid neutralization concentration (MNC) was defined as the lowest concentration of dentifrice at which acidification was inhibited. Differences between MIC and MNC were calculated and normalized with respect to MIC to derive the combined inhibitory and neutralizing capacity (CINC), a cumulative measure of acidogenesis-mitigation and growth inhibition. The overall rank order for growth inhibition potency (MIC) under aerobic and anaerobic conditions was: TD> SFD2> SFD1> FD. Acidogenesis-mitigation (MNC) was ordered; TD> FD> SFD2> SFD1. CINC was ordered TD> FD> SFD2> SFD1 aerobically and TD> FD> SFD1> SFD2 anaerobically. With respect to group-specific bactericidal activity, TD generally exhibited the greatest potency, particularly against total aerobes, total anaerobes and streptococci. This approach enables the rapid simultaneous evaluation of acidity mitigation, growth inhibition and specific antimicrobial activity by dentifrices

Comparative transcriptome analyses indicate molecular homology of zebrafish swimbladder and mammalian lung

10.1371/journal.pone.0024019PLoS ONE68

Chlorhexidine Improves Hygiene Reducing Oral Polymorphonuclear Leukocytes with Antimicrobial Effects at Distinct Microenvironments amongst Subjects Stratified by Health Status

Oral conditions such as gingivitis and oral malodor are commonly reported globally. Objective: This investigation clinically stratified subjects to healthy, malodor and gingivitis groups and enumerated oral polymorphonuclear leukocytes (PMN) as a measure of inflammation prior to and after rinsing with a chlorhexidine (CHX) mouthwash. The study also assessed clinical outcomes (dental plaque and gingival bleeding indices), malodor (halimeter scores, organoleptic and tongue coat index and microbiological parameters (anaerobic and malodor organisms of dental plaque, tongue surface and saliva) for a comprehensive assessment of the oral inflammatory burden. Methods: Consenting adults were stratified into control (n = 17), gingivitis (n = 19) and halitosis (n = 17) groups based on clinical criteria. At baseline, oral samples were examined for PMN in addition to microbiological analysis of dental plaque, saliva and tongue scrapings for anaerobic and malodor bacteria. Subjects were issued a commercially available fluoride toothpaste and a chlorhexidine mouthwash for two-week use prior to post-treatment assessments identical to baseline. Results: At baseline, PMN were lowest in the control that increased amongst the halitosis subjects, with the gingivitis group registering the highest levels (p p p p p Conclusions: At study enrollment, PMN scores were lowest in healthy subjects, with increasing numbers amongst halitosis followed by gingivitis. Amongst all subject groups, CHX use significantly reduced oral PMN and corroborated with corresponding decreases in clinical, malodor and bacterial outcomes. Together, these results demonstrate the significant reductions in the oral inflammatory burden following CHX use

Microbiological and clinical effects of an oral hygiene regimen

Objective: This study compared the additional effect of rinsing with a fluoride-free and alcohol-free 0.075% cetylpyridinium chloride (CPC) mouthwash to brushing alone on dental plaque, gingival inflammation, and supragingival plaque bacteria. Methods: Adult subjects [n = 68] completed a washout period prior to baseline evaluations that evaluated gingival inflammation, gingival bleeding, dental plaque, and pocket probing depths along with microbiological analysis of supragingival plaque for bacteria. Subjects were randomized to two treatment groups: brush with fluoride toothpaste and rinse with the CPC mouthwash (test) or brush with fluoride toothpaste only (control), twice daily for the next four weeks. Subjects abstained from oral hygiene for twelve-hours prior to two-week and four-week post-treatment microbiological analysis of supragingival plaque for bacteria. Clinical assessments for gingival inflammation, gingival bleeding, dental plaque, and pocket probing depths were conducted at the four-week post-treatment visit. Results: Compared to baseline, bacteria of dental plaque in the test group were reduced by 61.1% and 83.0% at the two-week and four-week evaluations, respectively (p < 0.05). Compared to baseline, bacteria of supragingival plaque in the control group were reduced by 2.3% at either post-treatment evaluations (p < 0.05). Additionally, dental plaque bacteria in the test was 69.8% and 86.8% lower than the control at the two-week and four-week evaluations (p < 0.05), respectively. After four-weeks, the test group showed 14.3% less gingivitis, 11.2% less dental plaque, 7.5% less gingival bleeding compared to the control group (p < 0.05). Conclusions: Oral hygiene comprising toothbrushing and rinsing with a mouthwash containing 0.075% cetylpyridinium chloride demonstrated greater reductions of dental plaque bacteria, improving gingival health, and eliminating supragingival plaque than toothbrushing alone

Multiparameter Assessments To Determine the Effects of Sugars and Antimicrobials on a Polymicrobial Oral Biofilm

Clinical studies indicate relationships between dental plaque, a naturally formed biofilm, and oral diseases. The crucial role of nonmicrobial biofilm constituents in maintaining biofilm structure and biofilm-specific attributes, such as resistance to shear and viscoelasticity, is increasingly recognized. Concurrent analyses of the diverse nonmicrobial biofilm components for multiparameter assessments formed the focus of this investigation. Comparable numbers of Actinomyces viscosus, Streptococcus sanguinis, Streptococcus mutans, Neisseria subflava, and Actinobacillus actinomycetemcomitans cells were seeded into multiple wells of 96-well polystyrene plates for biofilm formation. Quantitative fluorescence and confocal laser scanning microscopy (CLSM) examined the influences of dietary sugars, incubation conditions, ingredients in oral hygiene formulations, and antibiotics on biofilm components. Biofilm extracellular polymeric substances (EPS) were examined with an optimized mixture of fluorescent lectins, with biofilm proteins, lipids, and nucleic acids detected with specific fluorescent stains. Anaerobic incubation of biofilms resulted in significantly more biofilm EPS and extractable carbohydrates than those formed under aerobic conditions (P < 0.05). Sucrose significantly enhanced biofilm EPS in comparison to fructose, galactose, glucose, and lactose (P < 0.05). CLSM demonstrated thicker biofilms under sucrose-replete conditions, along with significant increases in biofilm EPS, proteins, lipids, and nucleic acids, than under conditions of sucrose deficiency (P < 0.05). Agents in oral hygiene formulations (chlorhexidine, ethanol, and sodium lauryl sulfate), a mucolytic agent (N-acetyl-l-cysteine), and antibiotics with different modes of action (amoxicillin, doxycycline, erythromycin, metronidazole, and vancomycin) inhibited biofilm components (P < 0.05). Multiparameter analysis indicated a dose-dependent inhibition of biofilm EPS and protein by chlorhexidine and sodium lauryl sulfate, along with distinctive inhibitory patterns for subinhibitory concentrations of antibiotics. Collectively, these results highlight multiparameter assessments as a broad platform for simultaneous assessment of diverse biofilm components