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PubMed2006

Influence of biosurfactant on interactive forces between mutans Streptococci and enamel measured by atomic force microscopy.

Although interactive forces, influenced by environmental conditions, between oral bacteria and tooth surfaces are important for the development of plaque, they have never been estimated. It is hypothesized that interactive forces, as measured by atomic force microscopy, between enamel with or without a pellicle and two strains of mutans streptococci become less attractive by the application of a Streptococcus mitis BMS biosurfactant coating. Upon approach of each of the strains toward bare and pellicle-coated enamel, adsorbed biosurfactant increased the range of the repulsive forces. Upon retraction of the enamel surface, small adhesion forces (0.8-0.9 nN) were measured for bare enamel that almost disappeared after biosurfactant coating. The prevalence and magnitude of the adhesion forces also decreased upon pellicle-coating of the enamel, with a minor effect of adsorbed biosurfactant. These findings indicate that adsorbed S. mitis BMS biosurfactant changes the interactive forces between the mutans streptococci studied and enamel, explaining the effects of biosurfactant on adhesion.

Adsorption↗
PubMed2003

Glucan-binding proteins of the oral streptococci.

The synthesis of extracellular glucan is an integral component of the sucrose-dependent colonization of tooth surfaces by species of the mutans streptococci. In investigators' attempts to understand the mechanisms of plaque biofilm development, several glucan-binding proteins (GBPs) have been discovered. Some of these, the glucosyltransferases, catalyze the synthesis of glucan, whereas others, designated only as glucan-binding proteins, have affinities for different forms of glucan and contribute to aspects of the biology of their host organisms. The functions of these latter glucan-binding proteins include dextran-dependent aggregation, dextranase inhibition, plaque cohesion, and perhaps cell wall synthesis. In some instances, their glucan-binding domains share common features, whereas in others the mechanism for glucan binding remains unknown. Recent studies indicate that at least some of the glucan-binding proteins modulate virulence and some can act as protective immunogens within animal models. Overall, the multiplicity of GBPs and their aforementioned properties are testimonies to their importance. Future studies will greatly advance the understanding of the distribution, function, and regulation of the GBPs and place into perspective the facets of their contributions to the biology of the oral streptococci.

Bacterial Adhesion↗
PubMed1994

An investigation of diterpenes from the leaves of Rabdosia trichocarpa and their antibacterial activity against oral microorganisms.

The ethanolic extract of Rabdosia trichocarpa leaves showed antibacterial activity against cariogenic mutans streptococci and periodontopathic Porphyromonas gingivalis. Chromatographic separation and purification of the extract afforded ten diterpenes, including one novel ent-kauren type compound named trichoranin. Some of these compounds possess potent antibacterial activity against these oral micro-organisms, indicating that these diterpenes may be useful natural substances for the maintenance of oral health.

Anti-Bacterial Agents↗
PubMed1997

Assessing the cariogenic potential of some infant formulas, milk and sugar solutions.

Using a desalivated rat model, the authors found that several commonly used infant formulas had significant cariogenic potential. Sucrose was by far the most cariogenic and cows' milk the least cariogenic of all the products examined. The data show that dental practitioners and other health care professionals should discourage the use of sugar in baby bottles and provide information on which formulas are least likely to induce caries when continuous bottle feeding is unavoidable.

Animals↗
PubMed2002

Bacterial, behavioral and environmental factors associated with early childhood caries.

The goals of this cross-sectional study were to characterize and compare demographic, behavioral, and environmental factors potentially associated with early childhood caries (ECC) and to assess salivary levels of mutans streptococci (MS) and lactobacilli (LB) in underserved, predominantly Hispanic children. One hundred forty-six children aged 3 to 55 months with a range of caries experience were identified and examined. ECC was primarily associated with the presence of MS and lack of access to dental care. Salivary MS levels among young children with ECC were higher than would be expected in a dentally healthy population, but lower than levels reported among older children at high risk for caries. After adjustment for age, children with log10 MS > or = 3.0 or log10 LB > or = 1.5 were about five times as likely (OR=4.9, 95% CI=2.0, 12.0) to have ECC than those with lower bacterial levels. This study demonstrated a significant association between relatively low cariogenic bacterial levels and dental caries in infants and toddlers. Antibiotic use, exposure to lead, and anemia were not significantly associated with the number of decayed and filled surfaces or decayed and filled teeth. ECC correlated significantly with child's age and lack of dental insurance of the children, as well as inversely with both family income and the educational level of the mother of the child.

Analysis of Variance↗
PubMed2004

Mutans streptococci, lactobacilli in saliva and acidity from organisms in dental plaque: changes after restorative treatment.

The effect of restorative dental treatment was evaluated on mutans streptococci and lactobacilli in saliva, as well as acid production by plaque bacteria. We used semiquantitative culture kits at time points up to 6 months following treatment. Changes in eating habits and oral hygiene during the study period were ruled out using a questionnaire. Mutans streptococci, lactobacilli, and acidity all had decreased significantly at 1 week after treatment. Acidity often was the first variable to return to pretreatment levels, while abundant at 6 than 3 months. Lactobacilli showed the most durable response to treatment. Restorative treatment achieves import temporary decreases in caries-associated bacteria, especially lactobacilli, without influence from potentially relevant behavioral changes. In addition, follow up examinations at relatively long intervals at least 3 month would appear most effective for dental health management.

Child↗
PubMed2004

Time of initial acquisition of mutans streptococci by human infants.

The aim of this study was to detect and monitor the acquisition of mutans streptococci (MS) in healthy Brazilian children. Samples of 4 different sites (saliva, tongue dorsum, dental ridges, and dental plaque, if teeth were present) were collected from 33 edentulous nursery school infants (5.9+/-1.5 month-old), using sterilized swabs, bi-monthly for 24 months. Saliva samples from the mothers were collected only once. After inoculation, and incubation typical morphotype colonies, were isolated and submitted to amplification by the technique of polymerase chain reaction (PCR) for identification. The PCR method identified 1667 strains as MS In 29 of the children's samples, the first positive culture for MS occurred at 15.3+/-4.6 months. At the end of the follow-up period, 77% of the children were classified as colonized and in 33% MS was found as a transient microorganism. A positive correlation was found between the time of MS acquisition by the infant and the number of erupted teeth (p<0.0001), and the time of emergence of the first tooth (p=0.0048). After 24 months, there were no dental caries, and 77% of children remained caries-free. These results indicate that MS colonization in this sample of low-income pre-school children may begin earlier than suggested by some investigations.

Age Factors↗
PubMed2006

Evaluation of fluoride release from teeth after topical application of NaF, SnF2 and APF and antimicrobial activity on mutans streptococci.

UNLABELLED: The objectives of this study were to evaluate and compare the amount and pattern of fluoride release from teeth after topical application of 2% NaF, 8% SnF2 and 1.23% APF at different time intervals. The growth inhibitory effects of this released fluoride ion was assessed on mutans streptococci (MS) and correlated with the fluoride release. Forty premolars divided into four groups were subjected to different topical fluoride treatments. All the teeth were immersed individually in deionized water and were transferred to containers at 1 hour, 1 day and 1 week time intervals. 240 samples in total were used for fluoride estimation by ion selective electrode method and the samples from the other subgroup were used for evaluation of antimicrobial activity on mutans streptococci (MS) by bacterial inhibition assay method. The results showed that the highest fluoride release (7.83 +/- 0.55 ppm) was seen in SnF2 treated specimens, as compared to that of NaF (3.71 +/- 0.60ppm) and APF (3.30 +/- 0.51ppm), the difference being statistically significant (P<0.01). This was observed immediately after 1 hour, followed by a drastic reduction thereafter. No zones of inhibition were observed at the released fluoride concentrations at different time intervals in the different groups. IN CONCLUSION: 8% SnF2 is expected to have greater anticaries property from the high fluoride releasing property for prolonged period of time.

Acidulated Phosphate Fluoride↗
PubMed1997

Dental caries and related factors in 88- and 92-year-olds. Cross-sectional and longitudinal comparisons.

Our aim was to compare two groups of 88- and 92-year-olds (n = 92 and n = 40), respectively, with regard to teeth, caries, and salivary and microbial conditions. Oral variables were analyzed in relation to functional capacity and use of cardiovascular agents and psychoactive drugs. Untreated root caries, plaque score, and counts of lactobacilli increased between the ages of 88 and 92 years (P < 0.01). Nine of the 24 longitudinally followed up subjects had lost 1-5 teeth over 4 years, and 17 subjects had developed new caries (DFS). The mean caries increment over 4 years was 1.3 coronal and 3.6 root surfaces, and new DFS per 100 surfaces at risk was 4.3 coronal and 17.5 root surfaces. Plaque score and final pH of buffer capacity increased (P < 0.05 and 0.01, respectively), whereas saliva flow, independent of gender, was unchanged. Use of cardiovascular agents and psychoactive drugs was associated with a deteriorated dental status.

Activities of Daily Living↗
PubMed2005

Antibacterial activities and bonding of MMSA/TBB resin containing amphiphilic lipids.

The purpose of this study was to investigate the antibacterial activity of MMA/TBB resin containing newly developed amphiphilic lipids. The amphiphilic lipids, C10-L-Ala/pts and C12-L-Ala/pts, synthesized from the reaction of n-alkyl alcohol and L-alanine were dissolved in MMA at concentrations of 0.5, 1.0, 1.5, and 2.0 mol%. Resin mixtures of PMMA powder and each MMA liquid containing lipid and TBB were prepared for all tests. Both lipids gave antibacterial effect to MMA/ TBB resin. The addition of C12-L-Ala/pts to MMA resulted in a significantly higher antibacterial activity than the addition of C10-L-Ala/pts. In terms of bond strength, the bond strength of MMA/TBB resin to bovine dentin was significantly decreased by the addition of amphiphilic lipids. But for enamel, the bond strength of MMA/TBB resin with amphiphilic lipids was clinically acceptable for orthodontic brackets. In conclusion, amphiphilic lipids will be useful as a component of adhesive resin to give the latter an antibacterial effect.

Acrylic Resins↗
PubMed1999

Effect of oleanolic acid-cyclodextrin inclusion compounds on dental caries by in vitro experiment and rat-caries model.

Earlier work in vitro showed that oleanolic acid (OA) was a potential inhibitor of insoluble glucan (ISG) synthesis from mutans streptococci (MS). In this study, two oleanolic acid-cyclodextrin inclusion compounds (OA-CDs), oleanolic acid-G1-beta-cyclodextrin (OA-G1-beta CD) and oleanolic acid-beta-cyclodextrin (OA-beta CD), were assayed for their effects on ISG synthesis from Streptococcus mutans MT8148R, and on the growth of oral bacteria. OA-beta CD inhibited ISG synthesis by 55.3 and 37.4% at 62.5 and 15.6 micrograms/ml of OA, respectively. Both OA-CDs inhibited the growth of MS, S. sanguis, and S. salivarius at 4 to 8 micrograms/ml of OA. The anticariogenic effect of the OA-beta CD was examined in a rat-caries model. Rats in the infected control groups showed the highest caries score. The infected treatment group B (0.5% OA in diet) showed lower scores than the control group. These results suggest that OA-beta CD is a potential anti-caries agent.

Animals↗
PubMed2000

Effect of surface roughness of porcelain on adhesion of bacteria and their synthesizing glucans.

STATEMENT OF PROBLEM: In some instances of porcelain restoration, refinishing is inevitable. In terms of plaque accumulation on porcelain, refinishing could be a substitute method for glazing. PURPOSE: This study compared the amount of adhesion of plaque components (bacterial cells and glucans) on porcelain disks with various degrees of surface roughness to assess the effects of surface roughness on the amount of plaque accumulation. MATERIAL AND METHODS: Radiolabeled cell suspensions were incubated with porcelain disks for 3, 8, and 24 hours at 37 degrees C, and the amounts of adhered cells and glucans were measured by using a liquid scintillation method. RESULTS: The amount of cells and glucans adhered on porcelain increased with incubation time. The surface roughness value and the amount of plaque adhesion decreased with the increase in polishing level. However, the greatest amount of plaque was adhered on glazed surfaces, although their surfaces were smoother than the surfaces polished with 120- or 600-grit abrasive papers. CONCLUSION: With the exception of glazed surfaces, a positive correlation between surface roughness and the amount of plaque accumulation was observed. Repolishing with a diamond paste would not induce problems of plaque accumulation, compared with an intact glazed surface.

Analysis of Variance↗
PubMed1997

[Effects of sodium doecyl sulfate on the artificial dental plaque in chemostat].

Sodium doecyl sulfate (SDS) is widely used as a detergent in dentifrices. It has been shown to interfere with the protein adsorption to hydroxyapatite (HA), and inhibit acquired pellicle formation. The aim of the present study was to examine the effects of SDS on the artificial dental plaque in chemostat. The amount of the 3H-labelled bacteria adhered on the enamel fragment surface was determined with scintillometer. The artificial dental plaque was observed under the scanning electron microscope. The results showed that enamel fragments treated with SDS adsorbed less bacteria than untreated ones, and had no plague formed. It suggested that SDS can inhibit the bacterial adherence on enamel surface and thus reduce dental plaque formation.

Actinomyces viscosus↗
PubMed2001

Mutans streptococci--in families and on tooth sites. Studies on the distribution, acquisition and persistence using DNA fingerprinting.

Mutans streptococci (MS) are bacteria showing several cariogenic traits. This thesis is based on the concept that humans acquire MS directly or indirectly from each other. Previous research on the transmission of the bacteria in families has indicated that children acquire MS from their mothers. Just a few studies have included fathers. Diverging results have been presented about spouses acquiring MS from each other. The information on the distribution of MS types at a tooth surface level has been limited. The methods used for identification of MS types have been refined during the years making further studies in the field interesting. The present thesis deals primarily with the distribution of MS in families. Twenty-five Swedish families including a 3-year-old first-born child (I) and 11 corresponding Chinese families (II) were studied. The Swedish families were followed up 2-5 years later (III and IV). Study V deals with the colonization of MS on tooth sites in 13 young adults. MS were isolated from bacterial plaque samples obtained from the teeth of the subjects. Identification of MS types was carried out through DNA analysis methods, REA and RAPD respectively. MS were detected in 11 of the 25 Swedish children. The distribution of MS genotypes in these families indicated that the mothers and individuals outside the family were the sources of MS to the children (I). The distribution of MS genotypes in the Chinese families (II) pointed to the fact that the father played a more pronounced role as MS source compared to in the Swedish families. The intra-familial distribution of MS seemed to be different in the two groups of families with different cultural backgrounds. At the follow-up, genotypes of MS were found again among the MS positive children and their parents. This indicated that genotypes of MS persisted. Even though some alterations in the prevalence of MS genotypes were shown (III). Among the MS negative children some had acquired the bacteria, but most of them remained MS negative by the age of 5-8 years (IV). The father was in some few cases the MS source to the child in the Swedish families (III, IV). Few spouses acquired MS from each other. It is not clear to which extent the parents' salivary levels of MS, caregiver of the child, breast-feeding or antibiotic treatment influenced the acquisition of MS in the groups studied (I-IV). Finally it was shown that several different genotypes of MS colonized a particular tooth site simultaneously. Within each individual the same genotype occurred on two or more tooth sites. Genotypes persisted 4-7 months on their site. The colonization diverged inter-individually in terms of the number and the distribution of MS genotypes on the tooth sites (V).

Adult↗
PubMed2002

[Anti-caries vaccines].

Even though the reduction of caries-incidence in developed countries, its increasing has been observed nowadays. The use of a vaccine was object of many researches, going under modifications and evaluations during years. Wallace and McCollum showed the chance to induce experimental cavities, while Clarke and McIntosh were the first underlining the roll of S. mutans and Lactobacilli as efforts of the pathology. Williams was the first working with humans and Zinner and Fitzgerald continued. So since Bowen the research tried to build a vaccine made of single bacterial molecules with antigenic power. We can count about a large number of targets, like: the Ag I/II, the glucosyltransferase enzyme (GTF), the glucan-binding-protein (GBP), the destranase, the fruttosyltransferase and the glucans. Among the substances used to obtain a vaccine cacao revealed its capacity against bacteria able to develop cavities, thanks to its cariostatic and anti-glucosyltransferase activity due to polyphenols, that we can find in green tea too. It's also interesting a technique that gives passive antibodies like cow's milk, but in particular the one of a monoclonal antibody made with biotechnology of plants: the Guy's 13. It does not show substantial differences in comparison with the human Ig and it's able to prevent the installation of micro-organism and to reduce cavities in adult patients already infected. For the setting-up of a vaccine, however, only studies, comparison and research will be able to show precise instruments of defence.

Antibodies, Monoclonal↗
PubMed2002

Detection of cariogenic Streptococcus mutans by quantitative polymerase chain reaction.

OBJECTIVE: To establish a kind of molecular biology clinical detective method to cariogenic S. mutans. METHODS: Using the coamplification of target and reference genes. One pair of specific primers were designed according to a portion of the dextranase (dexA) gene of S. mutans. The reference gene was plasmid pET23b DNA. The saliva samples of 196 children were quantitative detected. The PCR method was compared with the routine culture method. RESULTS: The rate of S. mutans counts >/= 10(8) CFU/L (colony-forming unit per millilitre) saliva by quantitative PCR was 91.3%. The results of coincidence rate between the new method and the routine way was 94.9%. CONCLUSIONS: The new quantitative detective method is fast and provides with high scoincidence rate and high specificity, so have extensive clinical practice foreground.

DNA Primers↗
PubMed2003

The paradigm shift in the etiology, prevention, and management of dental caries: its effect on the practice of clinical dentistry.

Treatment of dental caries as an infectious disease will require a paradigm shift in the way dentists and other health care professionals approach prevention and management of the disease. Prevention of dental caries has relied upon patient cooperation and often requires significant lifestyle changes that are at best difficult to implement and maintain or at worst ignored. This paradigm shift in the etiology, prevention, and treatment of dental caries demands that clinicians redirect their energies and emphasis from the "surgical" approach to dental caries to a "medical" strategy that focuses on early (prenatal if possible) risk assessment of the mother and implementation of appropriate therapeutic intervention, including use of antimicrobials, risk assessment of infants at 6 months of age, and a reduction in the levels of caries-producing bacteria. This revolution in how dentists practice and think will require that they develop strategies and curriculum to "retrain" practicing dentists and to train current and future dental students and residents as well as other medical colleagues on the essentials of the paradigm shift.

Anti-Infective Agents, Local↗