BACKGROUND: Smoking exerts an adverse effect on the periodontal tissue by reorganizing the ecosystem of oral microorganisms and is considered to be an important factor in the development of periodontal disease. Although cross-sectional studies on smokers and non-smokers have been attempted to investigate the microbial differences in periodontal oral cavity, only few studies have been conducted to investigate the changes in oral microorganisms during smoking cessation. The purpose of this study was to investigate the changes of bacteria in saliva and gingival crevicular fluid (GCF) over a period of one year among 11 smokers trying to quit smoking.METHODS: Eleven smokers trying to quit smoking visited the clinic at baseline, two weeks, two months, four months, six months, and 12 months to give saliva and GCF samples. The amounts of 16S rRNA, Porphyromonas gingivalis, Treponema denticola, Prevotella intermedia, Fusobacterium nucleatum subsp. nucleatum, Streptococcus mutans, and Streptococcus sobrinus in saliva and GCF were quantified using real-time polymerase chain reaction TaqMan probe assay. The results were analyzed by nonparametric statistical analysis using Friedman test and Spearman correlation coefficient.RESULTS: After cessation of smoking, the amounts of 16S rRNA corresponding to P. gingivalis, F. nucleatum, P. intermedia, and T. denticola in saliva decreased and then again increased significantly. The amount of F. nucleatum 16S rRNA in GCF decreased significantly after smoking cessation. Positive correlations were observed between 16S rRNA and F. nucleatum and between F. nucleatum and T. denticola in saliva and GCF.CONCLUSION: Even if the number of subjects in this study was small, we suggest that smoking cessation may reduce the total bacterial amount and F. nucleatum in GCF. However, the results regarding changes in the microbial ecosystem due to smoking or smoking cessation were inconsistent. Therefore, further in-depth studies need to be carried out.
Bacteria ; Bacterial Load ; Cross-Sectional Studies ; Ecosystem ; Fusobacterium nucleatum ; Gingival Crevicular Fluid ; Mouth ; Periodontal Diseases ; Porphyromonas gingivalis ; Prevotella intermedia ; Real-Time Polymerase Chain Reaction ; Saliva ; Smoke ; Smoking Cessation ; Smoking ; Streptococcus mutans ; Streptococcus sobrinus ; Treponema denticola

Polyphenon 60 refers to the mixture of catechins present in green tea. The aim of this study was to investigate the antimicrobial activities of polyphenon 60 against 4 strains of Streptococcus mutans and 2 strains of Streptococcus sorbrinus, which are the major causative bacteria of dental caries. The minimum bactericidal concentration (MBC) values of polyphenon 60 for S. mutans and S. sobrinus were determined and the effect of biofilm formation inhibition of that was evaluated. The MBC value of polyphenon 60 against the bacterial strains was 2.5 mg/ml except for one particular strain, S. mutans KCOM 1128 for which the value was 1.25 mg/ml. The results of biofilm formation inhibition assay revealed that polyphenon 60 inhibited biofilm formation more than 90% at a concentration of 2.5 mg/ml. It was apparent that polyphenon exhibited biofilm formation inhibition activity along with bactericidal effect against S. mutans and S. sobrinus. Therefore, it is proposed that polyphenon 60 as one of the components of bactericidal agents could be useful in developing oral hygiene products, toothpaste or gargling solution.
Bacteria ; Biofilms ; Catechin ; Dental Caries ; Oral Hygiene ; Streptococcus mutans ; Streptococcus sobrinus ; Streptococcus ; Tea ; Toothpastes

The aim of this study was to determine the efficacy of a 3 tone plaque disclosing gel in assessing the risk of caries related to the population of Streptococcus mutans, Streptococcus sobrinus, and Lactobacillus spp. quantified using a quantitative real-time polymerase chain reaction (qRT-PCR).15 healthy children of ages 9 – 12 years were randomly examined. The 3 tone plaque disclosing gel was applied on teeth surfaces, which changed the color to pink or red, blue or purple and light blue. Plaque was divided into 3 groups based on staining. Genomic DNA from each sample was subjected to a qRT-PCR assay for quantitative detection of target bacteria. The Kruskal-Wallis test was conducted for correlation between the color of plaque and the number of bacterial species.The levels of S. mutans, S. sobrinus, and Lactobacillus spp. were significantly different in the plaque samples of the 3 groups (p < 0.05). The proportion of S. sobrinus to S. mutans showed correlation to the color of plaque.The different color-dyed plaque was related to the number of acidogenic bacteria. The 3 tone plaque disclosing gel could be used as one of the indicators to assess the clinical risk of caries associated with the population of S. mutans, S. sobrinus, and Lactobacillus spp.
Bacteria ; Child ; Dental Caries ; Dental Plaque ; DNA ; Humans ; Lactobacillus ; Real-Time Polymerase Chain Reaction ; Streptococcus mutans ; Streptococcus sobrinus ; Tooth

This study aimed to evaluate the antimicrobial effects of Acanthopanax sessiliflorum fruit (ASF; Ogaza) extracts on Streptococcus mutans and Streptococcus sobrinus, which are agents that cause dental caries, and on Streptococcus mitis and Streptococcus salivarius, the microbial flora of the oral cavity. The ASF extracts obtained using 70% ethanol were fractionated in the order of ethyl acetate and n-Butanol, concentrated under reduced pressure, and lyophilized to give powdery solvent extracts. The antimicrobial activity of ASF extracts from each solvent was examined using the disk diffusion method. As a result, only those extracts obtained using an ethyl acetate solvent showed antimicrobial activity. These extracts were selected, and the minimum inhibitory concentration was measured by disk diffusion method at various extract concentrations. Results showed a minimum inhibitory concentration of 32 mg/ml. The viable cell count was measured to confirm the minimum bactericidal concentration. Results showed a minimum bactericidal concentration of 64 mg/ml. In the cytotoxicity test using normal human dermal fibroblast cells, the absorbance value of the test group was similar to that of the control group at 0.64, 1.28, and 6.4 mg/ml. The bacteria and their colonies were examined using a scanning electron microscope. Boundaries between the antimicrobial activity region and non-antimicrobial activity region were observed around the paper disk, which was immersed in the extract with 32 mg/ml concentration. Bacterial colonization was not observed in the area with antimicrobial activity. This finding suggests that ASF extracts can inhibit the growth of some microorganisms in the oral cavity, in addition to the effects of these extracts known to date. In particular, ASF extracts may be used as a preparation for preventing dental caries by adding the extract to the toothpaste or oral mouthwash.
1-Butanol ; Bacteria* ; Cell Count ; Colon ; Dental Caries ; Diffusion ; Eleutherococcus* ; Ethanol ; Fibroblasts ; Fruit* ; Humans ; Methods ; Microbial Sensitivity Tests ; Mouth ; Streptococcus ; Streptococcus mitis ; Streptococcus mutans ; Streptococcus sobrinus ; Toothpastes

OBJECTIVES: This study was conducted to determine whether Prunus mume extracts have an antimicrobial effect against Streptococcus mutans (S. mutans) and Streptococcus sobrinus (S. sobrinus). METHODS: The study used crushed and dried Prunus mume, to which 80% methanol was added to obtain extracts. The extracts then underwent a demarcation process, sequentially using hexane, chloroform, and ethyl acetate, all of which have different polarities, followed by a reduction in pressure . The disc diffusion method was then used to measure the clear zone diameter to identify the antimicrobial effect of Prunus mume extracts using the different solvents. The methanol extracts that presented antimicrobial activity against S. mutans and S. sobrinus were then selected, and their optical densities (3, 6, 9, 12, and 24 h after cultivation) were measured to identify growth retardation effects based on extract concentration (0.01, 0.1, 1, and 5 mg/ml). RESULTS: A clear zone was observed in methanol and ethyl acetate for S. mutans when the antimicrobial effect of Prunus mume extracts of each solvent against oral microorganisms was measured via the disc diffusion method. A clear zone was observed in hexane, chloroform, methanol, and ethyl acetate, when the extracts were tested for antimicrobial activity against S. sobrinus. The extract concentration of 1 mg/ml retarded growth with a statistical significance (P<0.05) from 6 h onwards, as determined when the optical density was measured hourly and the growth curves of S. mutans and S. sobrinus were plotted. CONCLUSIONS: Prunus mume extracts retarded the growth of S. mutans and S. sobrinus with increase in time and concentration. Therefore, Prunus mume extracts hold the potential to be used for developing an oral antimicrobial agent to control dental caries.
Bacteria* ; Chloroform ; Dental Caries ; Diffusion ; Methanol ; Methods ; Prunus* ; Solvents ; Streptococcus mutans ; Streptococcus sobrinus

PURPOSE: This study investigated the effects of silver nanoparticle (SN) loading into hydraulic calcium silicate-based Portland cement on its mechanical, antibacterial behavior and biocompatibility as a novel dental bone substitute. MATERIALS AND METHODS: Chemically reduced colloidal SN were combined with Portland cement (PC) by the concentrations of 0 (control), 1.0, 3.0, and 5.0 wt%. The physico-mechanical properties of silver-Portland cement nanocomposites (SPNC) were investigated through X-ray diffraction (XRD), setting time, compressive strength, solubility, and silver ion elution. Antimicrobial properties of SPNC were tested by agar diffusion against Streptococcus mutans and Streptococcus sobrinus. Cytotoxic evaluation for human gingival fibroblast (HGF) was performed by MTS assay. RESULTS: XRD certified that SN was successfully impregnated in PC. SPNC at above 3.0 wt% significantly reduced both initial and final setting times compared to control PC. No statistical differences of the compressive strength values were detected after SN loadings, and solubility rates of SPNC were below 3.0%, which are acceptable by ADA guidelines. Ag ion elutions from SPNC were confirmed with dose-dependence on the concentrations of SN added. SPNC of 5.0 wt% inhibited the growth of Streptococci, whereas no antimicrobial activity was shown in control PC. SPNC revealed no cytotoxic effects to HGF following ISO 10993 (cell viability > 70%). CONCLUSION: Addition of SN promoted the antibacterial activity and favored the bio-mechanical properties of PC; thus, SPNC could be a candidate for the futuristic dental biomaterial. For clinical warrant, further studies including the inhibitory mechanism, in vivo and long-term researches are still required.
Agar ; Anti-Bacterial Agents ; Bone Substitutes ; Calcium ; Colloids ; Compressive Strength ; Diffusion ; Fibroblasts ; Humans ; Nanocomposites ; Nanoparticles* ; Silver* ; Solubility ; Streptococcus mutans ; Streptococcus sobrinus ; X-Ray Diffraction

PURPOSE: This study investigated the effects of silver nanoparticle (SN) loading into hydraulic calcium silicate-based Portland cement on its mechanical, antibacterial behavior and biocompatibility as a novel dental bone substitute. MATERIALS AND METHODS: Chemically reduced colloidal SN were combined with Portland cement (PC) by the concentrations of 0 (control), 1.0, 3.0, and 5.0 wt%. The physico-mechanical properties of silver-Portland cement nanocomposites (SPNC) were investigated through X-ray diffraction (XRD), setting time, compressive strength, solubility, and silver ion elution. Antimicrobial properties of SPNC were tested by agar diffusion against Streptococcus mutans and Streptococcus sobrinus. Cytotoxic evaluation for human gingival fibroblast (HGF) was performed by MTS assay. RESULTS: XRD certified that SN was successfully impregnated in PC. SPNC at above 3.0 wt% significantly reduced both initial and final setting times compared to control PC. No statistical differences of the compressive strength values were detected after SN loadings, and solubility rates of SPNC were below 3.0%, which are acceptable by ADA guidelines. Ag ion elutions from SPNC were confirmed with dose-dependence on the concentrations of SN added. SPNC of 5.0 wt% inhibited the growth of Streptococci, whereas no antimicrobial activity was shown in control PC. SPNC revealed no cytotoxic effects to HGF following ISO 10993 (cell viability > 70%). CONCLUSION: Addition of SN promoted the antibacterial activity and favored the bio-mechanical properties of PC; thus, SPNC could be a candidate for the futuristic dental biomaterial. For clinical warrant, further studies including the inhibitory mechanism, in vivo and long-term researches are still required.
Agar ; Anti-Bacterial Agents ; Bone Substitutes ; Calcium ; Colloids ; Compressive Strength ; Diffusion ; Fibroblasts ; Humans ; Nanocomposites ; Nanoparticles* ; Silver* ; Solubility ; Streptococcus mutans ; Streptococcus sobrinus ; X-Ray Diffraction

OBJECTIVEThis study is to determine the common oral streptococcal adhesion forces by using composite resin and glass ionomer cement (GIC) with different degrees of surface roughness via atomic force microscopy (AFM) analysis. The influence of surface roughness on bacterial adhesion force is also discussed.

METHODSPolishing and grinding were applied to obtain 300, 200, 100, and 10 nm surfaces of light-cured composite resin and GIC samples. Surface topography was assessed by AFM analysis. Initial colonizers (Streptococcus sanguinis and Streptococcus mitis) and cariogenic bacterial strains (Streptococcus mutans and Streptococcus sobrinus) were used to obtain bacteria-modified AFM probes. The force-distance curves were also measured by AFM analysis to determine the adhesion forces of bacteria on the surfaces of the composite resin and GIC. Material surface roughness was analyzed using ANOVA, and adhesion forces were subjected to nonparametric analysis (Kruskal-Wallis test). Comparison among groups was performed by Dunn's test. Material surface roughness and bacterial adhesion forces were subjected to correlation analysis.

RESULTSBacterial adhesion forces increased with increasing material roughness. The adhesion forces of the four bacterial species reached the maximum on the material surface of 300 nm. The adhesion force of Streptococcus mutans increased from 0.578 nN to 2.876 nN on GIC surfaces with 10 and 300 nm roughness. The adhesion forces of the four species on the surface of the composite resin were stronger than that of GIC. The initial colonizers exhibited stronger adhesion forces to different materials than the cariogenic strains. Intergroup differences were evident on the 200 and 300 nm material surfaces.

CONCLUSIONSThe surface roughness of the material significantly affected the bacterial adhesion forces, and a significant linear correlation existed between both factors. The bacterial adhesion forces of the GIC were lower than that of the composite resin. Furthermore, surface roughness exhibited less influence on the cariogenic strains than that on the initial colonizers.

The purpose of this study was to develop Streptococcus sobrinus-specific qPCR primers based on the nucleotide sequence of the RNA polymerase β-subunit gene (rpoB). The specificity of the primers was determined by conventional polymerase chain reaction (PCR) with 12 strains of S. sobrinus and 50 strains (50 species) of non-S. sobrinus bacteria. The sensitivity of the primers was determined by quantitative real-time PCR (qPCR) with serial dilutions of the purified genomic DNAs (40 ng to 4 fg) of S. sobrinus ATCC 33478(T). The specificity data showed that the S. sobrinus-specific qPCR primers (RTSsob-F4/RTSsob-R4) detected only the genomic DNAs of S. sobrinus strains with a detection limit of up to 4 fg of S. sobrinus genomic DNA. Our results suggest that the RTSsob-F4/RTSsob-R4 primers are useful in detecting S. sobrinus with high sensitivity and specificity for epidemiological studies of dental caries.
Bacteria ; Base Sequence ; Dental Caries ; DNA ; DNA-Directed RNA Polymerases ; Epidemiologic Studies ; Limit of Detection ; Polymerase Chain Reaction ; Real-Time Polymerase Chain Reaction* ; Sensitivity and Specificity ; Streptococcus sobrinus* ; Streptococcus*

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.