OBJECTIVETo investigate the antagonistic effects of three species of oral Streptococcus on the growth of oral Saccharomyces albicans in vitro.

METHODSDirect inoculation method, reverse inoculation method and mixed culture methods were respectively chosen to observe the changes of Saccharomyces albicans colony formation on the effects of Streptococcus mutans, Streptococcus sanguis and Streptococcus salivarius.

RESULTS1) No clear inhibition zone was observed in each of the groups by direct inoculation method. 2) Compared with the control groups, Saccharomyces albicans colony formation on soft agar of Streptococcus sanguis decreased significantly (P < 0.05). 3) Mixed culture method results showed that Streptococcus mutans could inhibit the growth of Saccharomyces albicans significantly at different time points (P = 0.001). 4) Under the action of bacteria culture supernatant, the count of Saccharomyces albicans in experiment groups showed statistical significance when compared with the control groups at 24, 48, 72 h (P = 0.001); The differences among the experimental groups were of no statistical significance at majority times (P > 0.05).

CONCLUSIONStreptococcus mutans, Streptococcus sanguis, and Streptococcus salivarius could obviously inhibit the growth of Saccharomyces albicans in vitro. However, it is still unclear that among which the inhibition effects is stronger. The antagonistic effects is weakened gradually.

In Vitro Techniques ; Saccharomyces ; Streptococcus ; Streptococcus mutans ; Streptococcus sanguis

OBJECTIVETo explore the feasibility of methyl thiazolyl tetrazolium (MTT) colorimetric method and the applied condition for the normal bacteria in the mouth, as Streptococcus mutans (S. mutans), Streptococcus sanguis (S. sanguis), Haemophilus actinomycetemcomitans (H. actinomycetemcomitans).

METHODSColony forming units (CFU) which was the standard antitheses was used to count bacteria. This study would gain some parameters by changing wavelength, reactive time, dosage and so on. MTT colorimetric method was applied in the counting of S. mutans, S. sanguis and H. actinomycetemcomitans.

RESULTSWhen counting S. mutans, the best wavelength was 510 nm, the best range was 1.5 x 10(5) - 1.0 x 10(7) CFU x mL(-1). When counting S. sanguis, the best wavelength was 545 nm, the best range was 1.5 x 10(5) - 2.0 x 10(7) CFU x mL(-1). When counting H. actinomycetemcomitans, the best wavelength was 557 nm, the best range was 1.0 x 10(6) - 5.0 x 10(7) CFU x mL(-1). MTT colorimetric method can be used for different aged S. mutans, S. sanguis and H. actinomycetemcomitans.

CONCLUSIONOral bacteria could be counted by MTT colorimetric method, which is fast and convenient.

Aggregatibacter actinomycetemcomitans ; Bacteria ; Humans ; Saliva ; Streptococcus mutans ; Streptococcus sanguis

OBJECTIVETo study the effect of para-aminobenzoic acid (PABA) on the growth and metabolism of Porphyromonas gingivalis (P.g).

METHODSAfter adding different concentrations of PABA into the medium, anaerobic technique was applied to culture P.g. The products' A value and action of TLP was assayed, and P.g grew in the medium was observed by a scanning electron microscope.

RESULTSPABA promoted the growth of P.g and action of TLP, which would reach the highest level when PABA was 1 mg/L, and would decrease with the increasing of concentration of PABA. When the concentration arrived at 100 mg/L, PABA had no effect on them. In the mean time, PABA had effect on the form and adherence of P.g. When the concentration was 1 mg/L and 100 mg/L, this effect was strong, but as the concentration was 10 mg/L, the effect disappeared.

CONCLUSIONSPABA influences the growth and metabolism of P.g, which indicate that Streptococcus sanguis has regulative effect on the microecology of subgingival plaque.

4-Aminobenzoic Acid ; Dental Plaque ; Porphyromonas gingivalis ; metabolism ; Streptococcus sanguis

OBJECTIVETo evaluate the effects of Yili dark bee propolis on the main cariogenic biofilm and mechanisms.

METHODSSusceptibilities to the ethanolic extract of propolis against Streptococcus mutans (S. mutans), Streptococcus sobrinus (S. sobrinus), Streptococcus sanguis (S. sanguis), Actinomyces viscosus (A. viscosus), and Actinomyces naeslundii (A. naeslundii) were analyzed by crystal violet stain method to determine the minimum biofilm eradication concentration (MBEC). The biofilm was initially cultivated for 24 h. Subsequently, the propolis groups with different concentration MBEC and initial pH 7.0 were cultured for 24 h. Moreover, the pH value was measured to evaluate the acid-producing ability of the tested plaque biofilm. The effects of propolis on the insoluble extracellular polysaccharide synthesis of S. mutans biofilm were evaluated by anthrone method.

RESULTSThe MBEC of Yili propolis on S. mutans, S. sobrinus, S. sanguis, A. viscosus, and A. naeslundii were 6.25, 1.56, 3.13, 0.78, and 0.78 mg.mL-1, respectively. Propolis could decrease the ΔpH of the tested plaque biofilm, and the differences between the control and propolis groups were statistically significant (P<0.05). At MBEC, propolis could reduce the ability of S. mutans in synthesizing insoluble extracellular polysaccharides.

CONCLUSIONYili propolis demonstrate remarkable eradicative effects on the cariogenic plaque biofilm, showing inhibition of the synthesis of biofilm-produced acids and insoluble extracellular polysaccharides.

Actinomyces viscosus ; Animals ; Bees ; Biofilms ; Dental Plaque ; Propolis ; Streptococcus mutans ; Streptococcus sanguis ; Streptococcus sobrinus

STATEMENT OF PROBLEM: The microbial adhesion on the surface of materials used in prosthodontics and restorative dentistry significantly influences microbial infection. PURPOSE: The purpose of this study was to evaluate the effect of how the degree of surface roughness of acrlyic resin affect the adhesion of bacteria. MATERIAL AND METHODS: Resins were finished with 50micrometerand 250micrometeraluminium oxide particles by using sandblaster, by using stone point, and high polished with Opal(R) and Lace motor(R). The surface of acrylic resin attached by bacteria was directly touched on the surface of BHI agar, which was incubated. Bacteria colonies formed on BHI agar were counted in accordance with the degree of the surface roughness. RESULTS: 1. The viable cell number of Streptococcus mutans increased on the acrylic resins incubated in BHI broth than in PBS. 2. The viable cell number of Streptococcus mutans increased on the acrylic resins incubated without agitation than with agitation, washed three times than six times, and incubated in broth added with 5% sucrose than without sucrose. 3. When Streptococcus mutans incubated in BHI broth, the number of Streptococcus mutans colonies formed on BHI agar was the largest on the acrylic resins finished with 250micrometeraluminium oxide particle using sandblaster. But when incubated in BHI broth containing sucrose, the number of colonies formed on that was the largest on the acrylic resins high polished using Opal(R) and Lace motor(R). 4. When Streptococcus sanguis was incubated in BHI broth with or without sucrose, the number of Streptococcus mutans colonies formed on BHI agar was the largest on the acrylic resins finished with 250micrometeraluminium oxide particle using sandblaster. 5. When Actinomyces viscous was incubated in BHI broth with or without sucrose, the number of Streptococcus mutanscolonies formed on BHI agar was the largest on the acrylic resins high polished using Opal(R) and Lace motor(R). CONCLUSION: These results indicated that when acrylic resins attached by bacteria were touched on the surface of BHI agar, the number of bacterial colonies formed on the agar was dependent on the bacterial species. Also, the result of this study was showed that increase in the surface roughness and the addition of sucrose increased retention of microbial cells.
Acrylic Resins ; Actinomyces ; Agar ; Bacteria* ; Cell Count ; Dentistry ; Dihydroergotamine ; Prosthodontics ; Streptococcus ; Streptococcus mutans ; Streptococcus sanguis ; Sucrose

OBJECTIVETo compare the antibacterial effect between sodium fluoride and Galla Chinesis in bioflim model. To evaluate the feasibility of application of Gala Chinesis in the clinical practice of caries prevention.

METHODSStreptococcus mutans, Streptococcus sanguis, Streptococcus salivarius and Actinomyces naeslundii had been chosen as the experimental bacteria. In the experiment, biofilmn model was constructed, and two agents were added in the media. After a period of continuous culture, the number of bacteria adhering on the HA disc was examed, the planktonic pH in the flow cell was recorded continuously, and the morphology of the biofilmn formed on the HA disc was observed by SEM.

RESULTS(1) Galla Chinesis could inhibit the growth of the four oral bacteria in the biofilm just as sodium fluoride. (2) Galla Chinesis and sodium fluoride could prevent the descent of the planktonic pH in the flow cell, but Galla Chinesis was less efficient than sodium fluoride. (3) The biofilms formed after application of Galla Chinesis and fluoride, but the bacterial cells had less matrix than those applicated with sucrose.

CONCLUSIONGalla Chinesis is one kind of effective cariostatic natural agents.

Actinomyces ; Bacteria ; Biofilms ; Cariostatic Agents ; Dental Caries ; Fluorides ; Phosphates ; Sodium Fluoride ; Streptococcus mutans ; Streptococcus sanguis ; Sucrose

OBJECTIVEUsing MBEC-Assay to assay minimal biofilm eradication concentration (MBEC) of Galla Chinensis and Nidus Vespae to oral bacterial biofilm. To set up traditional Chinese medicine susceptibility pharmacodynamic empirical study methods of oral bacterial biofilm.

METHODSCariogenic bacteria strains were selected (Streptococcus mutans ATCC 25175, Streptococcus sanguis ATCC 10556, Lactobacillus rhamnosus AC 413, Actinomyces naeslundii WVU 627) in this study. Extraction components of Galla Chinensis were GCE (aqueous extract), GCE-B (30% alcohol extract) and extraction components of Nidus Vespae were NVE1 (95% alcohol extract). (1) To observe oral bacterial biofilm formatiom in MBEC-Device at different time. (2) MBEC-HTP-Assay: The minimal inhibitory concentration (MIC) and minimal biofilm eradication concentration (MBEC) of GCE, GCE-B and NVE1 to oral bacteria strains were determined.

RESULTSOral bacterial biofilm were readily formed on the lid of MBEC-Device under selected condition (observed by SEM). Oral cariogenic bacteria growing as plankton populations were sensitive to GCE, GCE-B and NVE1. To GCE, GCE-B and NVE1, oral cariogenic bacterial biofilm were 2-16 times less susceptible than growing plankton bacteria. GCE and GCE-B were the most effective medicine against oral cariogenic bacterial biofilm. NVE1 were effective in killing oral-bacterial biofilm at relatively high concentration.

CONCLUSIONGCE and GCE-B were effective medicine against oral cariogenic bacterial biofilm. MBEC (minimal biofilm eradication concentration) can provide a relative accurate medicine concentration for clinical test.

Bacteria ; Biofilms ; Dental Caries ; Microbial Sensitivity Tests ; Streptococcus mutans ; Streptococcus sanguis

The purpose of this study was to evaluate the effectiveness of chlorhexidine varnish treatment in the prevention of dental caries in orthodontic patients by observing microbial change in dental plaque after varnish treatment. The sample consisted of 26 patients who were classified into an experimental group and a control group, 13 patients each. The experimental group was treated with cl orhexidine varnish once a week for 4 weeks. The control group was treated with placebo varnish using the same procedure, The microbial change was analysed by indirect immunofluorescenize technique before treatment and 4 weeks, 8 weeks after treatment. The results were as follows. 1. Streptococcus inutans were strongly suppressed until 8 weeks after chlorhexidine varnish treatment(p<0.01). 2 The proportion of Streptococcus sanguis increased temporarily 4 weeks after chlorhexidine varnish treatment(p<0.U5), decreased to original level after 8 weeks. 3. Streptococcus mitts, Actinomyces viscosus, Actinomyces naeslundii did not show significant change after chlorhexidine varnish treatment.
Actinomyces ; Actinomyces viscosus ; Chlorhexidine* ; Dental Caries ; Dental Plaque* ; Humans ; Paint* ; Streptococcus ; Streptococcus sanguis

The authors observed the long term effects of chlorhexidine varnish treatment on microbial of dental plaque in orthodontic patients with fixed appliances. The initial sample was 100 patients who were arranged to be treated with fixed orthodontic appliances. The final sample consisted of 21 patients who could be traced for 32 weeks after application of fixed orthodontic appliances. They were classified into the experimental group (12 patients) and the control group (9 patients). The experimental group was treated with chlorhexidine varnish once a week for 4 weeks before application of fixed orthodontic appliance. The control group was not treated with chlorhexidine varnish before application of fixed orthodontic appliance. The experimental group was treated once more after 20 weeks. The microbial changes of dental plaque were analysed by indirect immunofluorescence technique at pre-treatment 4, 8, 20, and 32 weeks. The result were as follows. 1. In the experimental group, streptococcus mutans was significantly suppressed during experimental period. (p<0.01) But, in the control group, streptococcus mutans was significantly increased after placement of fixed orthodontic appliances during experiment period. (p<0.05) 2. Streptococcus sanguis, streptococcus mitis, Actinomyces viscosus, and Actinomyces naeslundii did not show significant change between the experimental and the control group during experiment period.
Actinomyces ; Actinomyces viscosus ; Chlorhexidine* ; Dental Plaque* ; Fluorescent Antibody Technique, Indirect ; Humans ; Orthodontic Appliances ; Paint* ; Streptococcus mitis ; Streptococcus mutans ; Streptococcus sanguis

OBJECTIVEThe purples of this study was to investigate the role of different components of Galla Chinensis extract on the growth of 6 kinds of cariogenic bacteria, and to find out the most effective components of Galla Chinensis extract.

METHODSFour different components (GCE1, GCE2, GCE3 and GCE4) were separated from Galla Chinensis and there antibacterial activities to Streptococcus mutans ATCC 25175, Streptococcus sanguis ATCC 10556, Streptococcus salivarius SS 196, Actinomyces naeslundii WVU 627, Actinomyces viscosus ATCC 19246 and Lactobacillus rhamnosus AC 413 were checked. There effects on the growth curve of Streptococcus mutans ATCC 25175 were also investigated.

RESULTSThe most effective part of Galla Chinensis was found to be GCE2 and GCE4, which were found to be a mixture of polyphenol-rich fractions. All of the different components had an inhibitory effect to the growth of Streptococcus mutans ATCC 25175.

CONCLUSIONAll of the 4 different components of Galla Chinensis extract could inhibit the growth of the tested bacteria. These results suggest that the antibacterial activity of Galla Chinensis extract is caused by a synergistic effect of monomeric polyphenols, which can easily bind to proteins.

Actinomyces viscosus ; Anti-Bacterial Agents ; Bacteria ; Dental Caries ; Drugs, Chinese Herbal ; In Vitro Techniques ; Streptococcus mutans ; Streptococcus sanguis