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Mutans Streptococci (mutan + streptococcus)
Selected AbstractsAbility of different restorative materials to prevent in situ secondary caries: analysis by polarized light-microscopy and energy-dispersive X-rayEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 4 2008Thaís Cachuté Paradella Secondary caries is the main cause of direct restoration replacement. The purpose of this study was to analyze enamel adjacent to different restorative materials after in situ cariogenic challenge using polarized-light microscopy (PLM), scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDS). Twelve volunteers, with a low level of dental plaque, a low level of mutans streptococci, and normal salivary flow, wore removable palatal acrylic appliances containing enamel specimens restored with Z250 composite, Freedom composite, Fuji IX glass-ionomer cement, or Vitremer resin-modified glass-ionomer for 14 days. Volunteers dripped one drop of 20% sucrose solution (n = 10) or distilled water (control group) onto each specimen 8 times per day. Specimens were removed from the appliances and submitted to PLM for examination of the lesion area (in mm2), followed by dehydration, gold-sputtering, and submission to SEM and EDS. The calcium (Ca) and phosphorus (P) contents were evaluated in weight per cent (%wt). Differences were found between Z250 and Vitremer, and between Z250 and FujiIX, when analyzed using PLM. Energy-dispersive X-ray analysis results showed differences between the studied materials regarding Ca %wt. In conclusion, enamel adjacent to glass-ionomer cement presented a higher Ca %wt, but this material did not completely prevent enamel secondary caries under in situ cariogenic challenge. [source] Dental caries and salivary status in children with type 1 diabetes mellitus, related to the metabolic control of the diseaseEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 1 2006Jolanta Siudikiene The aim of this study was to investigate the relationship among type 1 diabetes mellitus, dental caries, and salivary status in children. The study comprised 68, 10,15-yr-old diabetics, and 68, age- and gender-matched non-diabetic controls. Diabetics were categorized into well-to-moderately controlled (HbA1c <,9.0%) and poorly controlled (HbA1c , 9.0%) groups. Caries was recorded by assessing lesion activity at non-cavitated and cavity levels. Teeth were examined visually for the presence of dental plaque. Saliva was analyzed for unstimulated and stimulated flow rates, buffer effect, mutans streptococci, lactobacilli, and yeasts. Diabetics had fewer caries and plaque, lower salivary flow rates and buffer effect, and more frequent growth of yeasts than their non-diabetic controls. Well-to-moderately controlled diabetics had fewer decayed surfaces and lower counts of mutans streptococci and yeasts than poorly controlled diabetics, but the level of metabolic control of diabetes had no influence on salivary flow rates and buffer effect. High caries levels in diabetics were significantly associated with age, plaque score, and decreased unstimulated salivary flow rate, but were not associated with the level of metabolic control of diabetes. High caries experience in this study population could be related to plaque accumulation and/or to changes in saliva induced by diabetes mellitus. [source] Oral status of 35 subjects with eating disorders , A 1-year studyEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 4 2000Rolf Öhrn The aim was to record changes over time in the oral status of subjects with diagnosed eating disorders. The outpatient psychiatrist had referred to the hospital dental clinic 35 women (19,47 yr, median 27 yr) with eating disorders, diagnosed according to DSM III-R criteria. At the baseline examination, dental, medical and dietary histories were taken, and intra-oral clinical and radiographic examinations were supplemented by intra-oral photographs, study casts and salivary analysis. The subjects were re-examined 1 yr later. Together, the investigators assessed progression of tooth wear blindly by comparing coded study casts from the baseline and 12-month examinations. Progression of erosive tooth wear was recorded in almost half of the subjects. Several subjects had low unstimulated salivary flow rates (<0.1 ml/min) and very high counts of mutans streptococci and lactobacilli, both at baseline and 1 yr later. The flow rates for paraffin-stimulated saliva at baseline were significantly lower for subjects with progression of erosive tooth wear than for those without. Because of the increased susceptibility to both caries and erosion, patients with eating disorders should be encouraged to have regular dental check-ups. Test of salivary flow may serve as an indicator of patients' risk of progression of erosive tooth wear. [source] Molecular analysis of the inhibitory effects of oolong tea polyphenols on glucan-binding domain of recombinant glucosyltransferases from Streptococcus mutans MT8148FEMS MICROBIOLOGY LETTERS, Issue 1 2003M Matsumoto Abstract An oolong tea polyphenol (OTF6) has been shown to possess a strong anti-glucosyltransferase (GTF) activity and inhibit experimental dental caries in rats infected with mutans streptococci. The effects of OTF6 on the functional domains of GTFs of Streptococcus mutans, an N-terminal catalytic domain (CAT), and a C-terminal glucan-binding domain (GBD), were examined. The maximum velocity of glucan synthesis by recombinant GTFB (rGTFB) and GTFD (rGTFD) became significantly slower in the presence of OTF6, however, Km values remained stable when compared in their absence. These results suggest that OTF6 reduces glucan synthesis by non-competitively inhibiting the GBD of S. mutans GTFB and GTFD. Further, the recombinant proteins of CAT (rCAT) and GBD (rGBD) were expressed using Escherichia coli, and purified by affinity column chromatography. rGBD but not rCAT was found to possess dextran-binding activity, which was shown to be inhibited by OTF6. These results indicate that OTF6, a polymeric polyphenol specific for oolong tea is able to reduce glucan synthesis by inhibiting the GBD of S. mutans GTFB. [source] Ingredients in dentifrices and their effect on plaque, gingivitis and mutans streptococciINTERNATIONAL JOURNAL OF DENTAL HYGIENE, Issue 1 2004L Jannesson The main objectives of this thesis were to study: (i) the effect of an enzyme-containing dentifrice (Zendium Dentine®), with addition of xylitol on mutans streptococci (MS) in saliva and dental plaque (Paper I) (ii) the effect of a combination of triclosan and xylitol in a dentifrice (Colgate Total®) on MS in saliva and dental plaque (Paper II), and (iii) the effect of oxybenzone on prostaglandin E2 (PGE2)-production in cell culture and the effect of an oxybenzone-containing dentifrice on plaque, gingivitis and MS (Paper III). In Paper I, the subjects were divided into two test groups: one using a 10% xylitol and the other using a 5% xylitol dentifrice for 3 months. The addition of 10% xylitol to Zendium Dentine® had an inhibitory effect on MS in both saliva and dental plaque, and the effect of xylitol seemed to be dose dependent. In Paper II, three groups were using one of the following dentifrices: (i) Colgate Total® with addition of 10% xylitol; (ii) Colgate Total®; and (iii) Colgate Total® without triclosan and without xylitol. The results showed that the addition of 10% xylitol to Colgate Total® reduced the number of MS in saliva and plaque. This effect was more pronounced at 6 months than at 2 months. In Paper III, the effect of oxybenzone was studied in vitro and in vivo. Human Embryo Palatal Mesenchyme (HEPM) cells were used to test the inhibition of IL-1,-stimulated PGE2 production by different concentrations of oxybenzone. The results revealed that there was no decrease of cell viability up to 50 µm. A dose-dependent inhibition of stimulated PGE2 production was found: 50% inhibition (IC50) was found at 0.6 µm. Paper III also included a double-blind clinical trial testing two fluoride dentifrices: one with the addition of 0.5% oxybenzone and one without. Plaque index was reduced in both groups. There was no difference between the groups. A 25% reduction in gingival index was observed in the oxybenzone group after 6 weeks, compared to 2% in the placebo group, indicating an anti-inflammatory effect of oxybenzone. [source] Probiotics and oral health effects in childrenINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 1 2008SVANTE TWETMAN Background., Probiotics are living micro-organisms added to food which beneficially affect the host by improving its intestinal microbial balance. Objective., This paper aims to present a general background on probiotics and its health effects in children, and to examine the evidence for oral colonization and the possible impact on oral health in children and young adults. Methods., For delivery and general health effects, recent systematic reviews, meta-analyses, and other relevant papers were used. Concerning oral installation and oral effects, a broad search for publications in English was conducted through February 2007 in PubMed. Studies describing an installation or intervention trial in humans with a controlled design and an oral endpoint measure were considered. Fourteen papers with dental focus were identified, of which two were narrative reviews. Results., Only one study of dental interest was conducted in children. Four papers dealt with oral installation of probiotic bacteria, and although detectable levels were found in saliva shortly after intake, the studies failed to demonstrate a long-term installation. Seven papers evaluated the effect of lactobacilli- or bifidobacteria-derived probiotics on the salivary levels of caries-associated bacteria in placebo-controlled designs. All but one reported a hampering effect on mutans streptococci and/or yeast. The single study carried out in early childhood reported a significant caries reduction in 3- to 4-year-old children after 7 months of daily consumption of probiotic milk. Conclusion., Bacteriotheraphy in the form of probiotic bacteria with an inhibitory effect on oral pathogens is a promising concept, especially in childhood, but this may not necessarily lead to improved oral health. Further placebo controlled trials that assess carefully selected and defined probiotic strains using standardized outcomes are needed before any clinical recommendations can be made. [source] Dental health and oral mutans streptococci in 2,4-year-old Estonian childrenINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 2 2007JANA OLAK Objective., The aim of this study was to assess the dental health and presence of mutans streptococci (MS) in 2,4-year-old Estonian children. Methods., The dental health of 472 2,4-year-old children was examined using a mirror and a penlight in 14 daycare centres representing seven communities around Estonia. The mean (± SD) age of the children was 41.4 ± 4.1 months (n = 222). Plaque samples of 222 children were employed to determine the presence of MS using the Dentocult® SM Strip mutans test. Results., Caries was diagnosed in 42% of the children, and the average (± SD) dmft index was 1.6 ± 2.5, ranging from 1.1 ± 1.2 in Tartu to 2.4 ± 3.1 in Võru. The proportion of caries-free children decreased from 82% in the younger to 63% in the older group (P = 0.001). Among the tested subjects, 58% were colonized with MS, and those with caries were colonized more often than children with no visible caries (80% and 51%, respectively; P = 0.001). Conclusions., The prevalence of dental caries in Estonian 2,4-year-olds is higher than in the Nordic countries, but similar to other Baltic nations. Colonization by MS was associated with dental caries. [source] Mutans streptococci in subgingival plaque of treated and untreated patients with periodontitisJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 7 2001W. A. Van Der Reijden Abstract Background: The etiology of root caries is thought to be identical to coronal caries, though root caries seem to be more complicated because of the higher susceptibility of exposed roots (dentin) by periodontal therapy to demineralization than intact enamel. This implies that mutans streptococci are the most likely pathogens in the development of root caries. Although it is known that both the numbers of mutans streptococci and the frequency of isolation in root caries lesions are negatively correlated with the distance from the gingival margin, the subgingival sulcus has not been considered a possible habitat for mutans streptococci. However, subgingival occurence of mutans streptococci in both untreated and treated periodontal patients has not been documented well in the literature. Objective: To investigate the presence and levels of mutans streptococci in the subgingival plaque of patients (n=154) in different stages of periodontal therapy. The subgingival sulcus may be a possible habitat for mutans streptococci. This localisation of mutans streptococci may be of importance in the development of root caries after periodontal surgery. Materials and methods: In this cross-sectional study, subgingival plaque samples from 154 consecutive adult periodontitis patients were tested for presence and levels of mutans streptococci and putative periodontal pathogens by anaerobic cultures. These patients were divided into 4 groups based on their stage of periodontal treatment: (1) untreated patients; (2) patients after initial periodontal therapy only; (3) patients in the maintenance phase who not underwent periodontal surgery; (4) patients after periodontal surgery. Results: The prevalence of mutans streptococci in the 4 study groups varied from 82% in untreated patients to 94% in maintenance patients. The mean proportion of mutans streptococci was 6.65% in maintenance patients versus 1.86% in untreated patients (p=0.005) and 2.51% in patients after scaling and root planing (p=0.041). Conclusions: The subgingival area is a microbial habitat for mutans streptococci that may be of importance in the development of root caries in periodontitis patients. Zusammenfassung Hintergrund: Es wird angenommen, dass die Ätiologie der Wurzelkaries und der Kronenkaries übereinstimmen, obwohl die Entstehung von Wurzelkaries komplizierter zu sein scheint wegen der erhöhten Empfindlichkeit entblößter Wurzeln (Dentin) für Demineralisation im Vergleich zu gesundem Schmelz. Das bedeutet, dass MS die wahrscheinlichsten Pathogene für die Entstehung der Wurzelkaries sind. Obwohl bekannt ist, dass die Zahl der MS und die Häufigkeit ihres Nachweises aus Wurzelkariesläsionen negativ mit dem Abstand vom Gingivarand korrelieren, wurde die subgingivale Region bisher nicht als möglicher Lebensraum für MS erwogen. Das subgingivale Vorkommen von MS bei behandelten und unbehandelten Parodontitispatienten ist in der Literatur nicht gut dokumentiert. Die subgingivale Region könnte ein möglicher Lebensraum für MS und diese Lokalisation bedeutsam für die Entstehung von Wurzelkaries nach parodontaler Therapie sein. Zielsetzung: Untersuchung des Vorkommens und der Menge von MS in der subgingivalen Plaque von Patienten zu unterschiedlichen Zeitpunkten parodontaler Therapie. Material und Methoden: In einer Querschnittsstudie wurden subgingivale Plaqueproben von 154 Patienten mit Erwachsenenparodontitis auf das Vorkommen und den Anteil von MS und putativer Parodontalpathogene in anaerober Kultur untersucht. Die Patienten wurden nach dem Stadium der parodontalen Therapie in 4 Gruppen unterteilt: (1) unbehandelte Patienten (n=51), (2) Patienten nach abgeschlossener Initialtherapie (Mundhygieneunterweisungen sowie Scaling und Wurzelglättung [SRP]) (n=41), (3) Patienten in der unterstützenden Parodontitistherapie (UPT), die nicht parodontalchirurgisch behandelt worden waren (n=48), und (4) Patienten nach Parodontalchirurgie (n=14). Ergebnisse: Die Prävalenz der MS variierte in den 4 Untersuchungsgruppen von 82% bei unbehandelten bis 94% bei UPT-Patienten. Der mittlere Anteil der MS an subgingivaler Plaque lag bei 6.65% (UPT) im Vergleich zu 1.86% (unbehandelte Parodontitis) (p=0.005) bzw. zu 2.51% (SRP) (p=0.041) und 2.18% nach Parodontalchirurgie (n.s.) Schlußfolgerungen: Die subgingivale Region ist ein Lebensraum für MS, die eine Bedeutung für die Pathogenese der Wurzelkaries bei Patienten mit Parodontitis haben könnte. Résumé L'étiologie des caries radiculaires semble étre identique à celle des caries coronaires bien que les caires radiculaires paraîssent plus compliquées vu la susceptibilité plus importante des racines exposées (dentine) par le traitement parodontal à la même déminéralisation que ne l'est l'émail intact. Ceci a comme conséquence que les Streptocoques mutans sont vraisemblabement les pathogènes les plus problables dans le dévelopment des caries radicularies. Bien qu'il soit connu que les nombres de Streptocoques mutans autant que la fréquence de l'isolation des lésions carieuses radiculaires soient en corrélation négative avec la distance depuis la gencive marginale, le sulcus gingival n'a pas été considéré comme habitat possible pour les Streptocoques mutans. Cependant, l'occurence sous-gingivale des Streptocoques mutans chez les patients avec parodontite traitée ou non n'a pas été suffisamment documentée dans la littérature. Le but de cette étude a été d'analyser la présence et les niveaux de Streptocoques mutans dans la plaque sous-gingivale de 154 patients à différentes étapes de leur traitement parodontale. Le sillon sous-gingival pourrait dont être un habitat possible pour les Streptocoques mutans. Cette localisation peut être importante dans le dévelopment des caries radiculaires après le traitement parodontal. Dans cette étude croisée des échantillons de plaque sous-gingivale ont été prélevés chez 154 patients adultes avec parodontite pour vérifier la présence et les niveaux de Streptocoques mutans et d'autres pathogènes parodontaux putatifs par culture anaérobie. Les patients étaient divisés en 4 groupes suivant le stade de leur traitement parodontal: non-traité, traitement initial seulement, phase de maintien mais sans chirurgie, et patient après chirurgie parodontale. La fréquence globale des Streptocoques mutans dans les 4 goupes variaient de 82% chez les patients non-traités à 94% chez ceux au stade de maintenance. La proportion moyenne de Streptocoques mutansétaient de 6.65% chez les patients en maintenance versus 1.86% chez les patients non-traités (p=0.005) et de 2.51% chez les patients après détartrage et surfaçage radiculaire (p=0.041). L'aire sous-gingivale est donc un habitat microbien pour les Streptocoques mutans qui pourraient être assez importants dans le développement des caries radiculaires chez les patients souffrant de parodontite. [source] Antibacterial activity of silver inorganic agent YDA fillerJOURNAL OF ORAL REHABILITATION, Issue 4 2004S. Ohashi summary, YDA filler is an antibacterial agent that is currently in commercial dental use. In this study, we attempted to determine whether it exerts an antibacterial effect on human saliva bacteria, and to determine whether it can be used in dental materials. CFUs in 1 mL stimulated human saliva were examined using blood agar and mitis salivarius agar after immersion, with or without YDA filler. The antibacterial effect was compared with that of Ketac-Silver. Dental materials containing 5% wt YDA filler were prepared for in vitro testing on S. mutans and A. viscosus. Furthermore, we examined the in vitro cytotoxicity of experimental MMA resin containing YDA filler on HeLa cells. Human saliva bacteria and mutans streptococci showed reduced viability following exposure to YDA filler after 12 h. The concentration of silver ions released by YDA filler was below 1 ppm after 12 h. Two tested strains showed reduced viability following exposure to dental materials containing YDA filler. In another experiment, MMA resin containing YDA filler did not show cytotoxicity on HeLa cells after 24- and 48-h exposure. Thus, YDA filler may help in the development of antibacterial dental materials, such as composite resin, glass,ionomer or temporary cement. [source] A synergistic chlorhexidine/chitosan combination for improved antiplaque strategiesJOURNAL OF PERIODONTAL RESEARCH, Issue 5 2005E.-M. Decker Background:, The minor efficacy of chlorhexidine (CHX) on other cariogenic bacteria than mutans streptococci such as Streptococcus sanguinis may contribute to uneffective antiplaque strategies. Methods and Results:, In addition to CHX (0.1%) as positive control and saline as negative control, two chitosan derivatives (0.2%) and their CHX combinations were applied to planktonic and attached sanguinis streptococci for 2 min. In a preclinical biofilm model, the bacteria suspended in human sterile saliva were allowed to attach to human enamel slides for 60 min under flow conditions mimicking human salivation. The efficacy of the test agents on streptococci was screened by the following parameters: vitality status, colony-forming units (CFU)/ml and cell density on enamel. The first combination reduced the bacterial vitality to ,0% and yielded a strong CFU reduction of 2,3 log10 units, much stronger than CHX alone. Furthermore, the first chitosan derivative showed a significant decrease of the surface coverage with these treated streptococci after attachment to enamel. Conclusions:, Based on these results, a new CHX formulation would be beneficial unifying the bioadhesive properties of chitosan with the antibacterial activity of CHX synergistically resulting in a superior antiplaque effect than CHX alone. [source] Oral Health of Young Children in Mississippi Delta Child Care Centers: A Second Look at Early Childhood Caries Risk AssessmentJOURNAL OF PUBLIC HEALTH DENTISTRY, Issue 4 2008Linda H. Southward PhD Abstract Objectives: To identify the predictors of early childhood caries and urgent dental treatment need among primarily African-American children in child care centers in the Delta region of Mississippi. The purpose of this study was to replicate predictors of caries and urgent dental treatment needs that were identified in an earlier study conducted in Delta child care centers and to assess additional caries risk factors not collected in the original study. Methods: Children in 19 child care centers were examined by the dentists, and the parents provided data on oral health practices, oral health history, and on children's oral health-related quality of life (QOL). The dentists also assessed visible plaque and tested levels of mutans streptococci. Predictors of caries and treatment need among children 24 to 71 months of age were examined using logistic regression. Results: Two parent predictors of caries identified in the earlier study (parent flossing and soft/sugary drink consumption) were not predictive in the current study. Parent history of abscess continued to predict their child's urgent need for treatment. Young children's level of salivary mutans streptococci, maxillary incisor visible plaque, and parents' reports of child oral health-related QOL measures predicted the presence of both caries and urgent treatment need. Some expected predictors, such as frequency of child's toothbrushing, were not predictive of caries. Conclusions: Parental abscess and parent's report of the child's oral health-related QOL are risk indicators for poor oral health outcomes that could be used by nondental personnel to identify young children in need of early preventive intervention and dental referral. [source] Factors Associated with Dental Caries Experience in 1-Year-Old ChildrenJOURNAL OF PUBLIC HEALTH DENTISTRY, Issue 2 2008John J. Warren DDS Abstract Objectives: Dental caries in early childhood is an important public health problem. Previous studies have examined risk factors, but they have focused on children during the later stages of the disease process. The purpose of this study was to assess the factors associated with caries in children aged 6 to 24 months as part of a cross-sectional analysis. Methods: Two hundred twelve mothers with children 6 to 24 months of age were recruited from Special Supplemental Nutrition Program for Women, Infants, and Children clinic sites in southeastern Iowa for participation in a longitudinal study of dental caries. Baseline assessments included detailed questions regarding the children's beverage consumption, oral hygiene, and family socioeconomic status. Dental caries examinations using the d1d2-3f criteria and semiquantitative assessments of salivary mutans streptococci (MS) levels of mother and child were also conducted. Counts of the number of teeth with visible plaque were recorded for maxillary and mandibular molars and incisors. Results: Of the 212 child/mother pairs, 187 children had teeth. Among these children, the mean age was 14 months, and 23 of the children exhibited either d1, d2-3, or filled lesions. Presence of caries was significantly associated with older age, presence of MS in children, family income <$25,000 per year, and proportion of teeth with visible plaque. Conclusions: Results suggest that not only microbial measures, including MS and plaque levels, are closely associated with caries in very young children, but that other age-related factors may also be associated with caries. Continued study is necessary to more fully assess the risk factors for caries prevalence and incidence in preschool children. [source] New serotype of mutans streptococci isolated from pig oral cavityMICROBIOLOGY AND IMMUNOLOGY, Issue 2 2008Kazuko Takada ABSTRACT Gram-positive streptococcal mutans-like strains, but with clearly different colony formation than S. orisuis on Mitis Salivarius agar, were isolated from the pig oral cavity and identified by 16S rRNA sequencing, G+C content, DNA-DNA homology and extensive biochemical and serological testing. The phenotypic data showed that the strains were similar to S. orisuis except for susceptibility to bacitracin. DNA-DNA homology between the isolates and S. orisuis was 72,81%. However, serological data showed that they have a different sero-specific antigen from S. orisuis and other mutans streptococci. A new serotype, designated p, strains are classified in a serovar of S. orisuis, one of mutans streptococci. [source] Non-oral bifidobacteria and the aciduric microbiota of the denture plaque biofilmMOLECULAR ORAL MICROBIOLOGY, Issue 3 2010M. Mantzourani Summary The microbiota of the denture plaque biofilm colonizing the fitting surface of dentures in edentulous subjects with healthy palates (n = 20) and in edentulous subjects with denture stomatitis (n = 20) was studied. The numbers of bacteria colonizing the dentures of healthy subjects was significantly less than the numbers colonizing the dentures of stomatitis subjects. The proportions and frequency of isolation of mutans streptococci, lactobacilli, bifidobacteria and yeasts were significantly (P < 0.05) greater in the subjects with denture stomatitis. The proportions of these organisms in the denture plaque biofilm of the subjects with denture stomatitis were similar to those found in carious lesions, indicating that the site is a low pH environment. The predominant bifidobacterial species in the mouths of dentate subjects is Bifidobacterium dentium but in the edentulous subjects wearing dentures B. dentium was isolated from only one of the 20 subjects with denture stomatitis and from none of the 20 subjects with healthy palates. Instead, Bifidobacterium breve, Bifidobacterium scardovii and Bifidobacterium longum subsp. longum were isolated. Only a single non-oral bifidobacterial species was isolated from each individual and repetitive extragenic palindromic- and BOX-polymerase chain reaction typing methods indicated that the same genotypes were shared between subjects. Using deferred antagonism spot plate assays, interspecies inhibition was demonstrated between oral isolates of B. dentium, B. breve, B. scardovii and B. longum subsp. longum. Here we have shown that bifidobacteria and caries-associated microbiota are present in denture plaque at levels similar to those of carious lesions and B. dentium cannot be maintained in an edentulous mouth. [source] Automutanolysin disrupts clinical isolates of cariogenic streptococci in biofilms and planktonic cellsMOLECULAR ORAL MICROBIOLOGY, Issue 6 2009P. Thanyasrisung Introduction:, Dental caries remains one of the most common chronic infectious diseases throughout the world. The formation of dental plaque is one of the caries risk factors. As a consequence, the removal of plaque may reduce the incidence of caries development. We identified an autolysin produced by Streptococcus mutans named auto-mutanolysin (Aml). Aml selectively lyses S. mutans and Streptococcus sobrinus. The specificity towards these cariogenic bacteria suggests that Aml may be used to prevent dental caries. Here, with the aim towards therapeutic application, we investigated the lytic activity of Aml against clinical isolates of S. mutans and S. sobrinus using planktonic cells and biofilms. Methods:, Planktonic cell suspensions and biofilms of clinically isolated streptococci were treated with Aml in the absence or the presence of Triton X-100. The lytic activity of Aml was monitored as the change in turbidity. The disruption of biofilms was evaluated by detecting the released DNA by polymerase chain reaction and observing the alteration of optical density of treated biofilms. Results:, Triton X-100 enhances the lytic ability of Aml. Using planktonic cells, Aml had various lysis levels against clinical strains. Repeated Aml treatment showed disruption of the biofilm using the representative clinical strains. Conclusion:, Our study demonstrates that Aml has an ability to lyse planktonic and biofilm cells of clinically isolated mutans streptococci in the presence of Triton X-100. These results suggest the possibility of using Aml as an alternative or additional approach for caries prevention. [source] Bacterial composition and red fluorescence of plaque in relation to primary and secondary caries next to composite: an in situ studyMOLECULAR ORAL MICROBIOLOGY, Issue 1 2008R. Z. Thomas Background/hypothesis:, Secondary caries has been suggested as the main reason for restoration replacement. We hypothesized that more caries-associated bacteria are found on composite resin restoration material, compared to sound tooth tissue. Methods:, Both restored and unrestored dentin and enamel samples were placed in a full denture of eight subjects for 20 weeks. The microbiological composition of approximal plaque and the association between caries-associated bacteria and red autofluorescence of dental plaque was studied. Every 4 weeks the specimens were microradiographed using transversal wavelength independent microradiography (T-WIM). After 1 and 20 weeks red fluorescence pictures and plaque samples were taken. Samples were cultured for total anaerobic counts, mutans streptococci, lactobacilli, candida and Actinomyces odontolyticus. Results:, Lesion depth in the dentin and enamel was positively associated with lactobacilli, and lesion depth in dentin was positively associated with A. odontolyticus, whereas no association was found between mutans streptococci and lesion depth. The red-fluorescent bacteria A. odontolyticus and lactobacilli did not correlate with red-fluorescent plaque, indicating that red fluorescence is probably not caused by a single species of these bacteria. After 20 weeks, a higher proportion of combined mutans streptococci and lactobacilli was found on restored tissue compared to non-restored tissue (P = 0.04). Conclusion:, The higher proportion of caries-associated bacteria on restored tissue indicates that the ecology on the surface of primary lesions differs from that on lesions next to composite, and that secondary caries next to composite may differ from the primary caries process. [source] Effects of antibodies against a fusion protein consisting of parts of cell surface protein antigen and glucosyltransferase of Streptococcus sobrinus on cell adhesion of mutans streptococciMOLECULAR ORAL MICROBIOLOGY, Issue 1 2008T. Kawato Background/aims:, The cell surface protein antigen (PAg) and glucosyltransferases (GTFs) produced by Streptococcus sobrinus are considered to be major colonization factors of the organism. Methods:, We constructed a fusion gene encoding a protein composed of the alanine-rich region of PAg (PAgA) and the glucan-binding domain (GB) of GTF-I, which catalyzes the synthesis of water-insoluble glucan in S. sobrinus. The fusion protein PAgA-GB was purified from cell extracts of Escherichia coli harboring the fusion gene, and antibodies against the fusion protein were prepared in rabbits. Results:, In the presence of sucrose, the antibody against PAgA-GB significantly inhibited the adhesion of both S. sobrinus MT8145 and Streptococcus mutans Xc to saliva-coated hydroxyapatite beads, and the inhibitory effect on S. sobrinus was stronger than that on S. mutans. In the absence of sucrose, the antibody against PAgA-GB significantly inhibited the adhesion of both S. sobrinus and S. mutans, however the inhibitory effect on S. sobrinus was unexpectedly weaker than that on S. mutans. A similar result was observed with the antibody against the intact recombinant PAg protein (rPAg), while the same antibody reacted more strongly against S. sobrinus than against S. mutans cells. Conclusion:, Taken together, these results show that the antibody against S. sobrinus GTF-I may be useful for effective inhibition of the sucrose-dependent adhesion of S. sobrinus. However, PAg of S. sobrinus may not function primarily as a receptor for acquired pellicles, and other cell surface proteins may be involved in the sucrose-independent adhesion of S. sobrinus. [source] Low salivary IgA activity to cell-surface antigens of mutans streptococci related to HLA-DRB1*04MOLECULAR ORAL MICROBIOLOGY, Issue 2 2005M. L. L. Wallengren Background/aims:, Mutans streptococci are found in almost all individuals, though there are large differences in colonization levels between individuals. These differences are not readily explained, though several factors are believed to influence the colonization. One factor is the immune response to mutans streptococci, mainly provided by salivary immunoglobulin A (IgA). In a previous study, differences in salivary IgA reactions to oral streptococci were observed between human leukocyte antigen (HLA)-DR4-positive and DR4-negative individuals. A lower salivary IgA activity to Streptococcus mutans in particular was most pronounced for two DR4 subgroups, DRB1*0401 and *0404. The main purpose of this study was to further investigate, in a larger study group, the salivary IgA activity to antigens of three oral streptococci in relation to different HLA-DRB1*04 alleles. Methods:, Stimulated saliva was collected from 58 HLA-DRB1*04-positive individuals. Whole cell antigen extracts from S. mutans, Streptococcus sobrinus and Streptococcus parasanguis and the streptococcal antigen (SA) I/II were separated in SDS-PAGE, transblotted and detected with diluted saliva (Western blot), and analyzed in a computer program. All distinct immunoblot bands over 100 kDa were recorded and compared in relation to DRB1*04. Results:, The immunoblots revealed lower salivary IgA reactions to S. mutans, S. sobrinus and SA I/II, but not to S. parasanguis, for the DRB1*0401- and *0404-positive individuals compared to other DRB1*04 types. For the *0401 subgroup there was a significant association with a lower IgA response to S. mutans. Conclusion:, The results confirm earlier observations and may also support previous demonstrated association between colonization by mutans streptococci and the serologically defined HLA-DR4. [source] Determination of mutacin activity and detection of mutA genes in Streptococcus mutans genotypes from caries-free and caries-active childrenMOLECULAR ORAL MICROBIOLOGY, Issue 3 2003P. L. Longo Relationships between genetic diversity, mutacin production and sensitivity to mutacins in Streptococcus mutans were evaluated in 19 clinical isolates from caries-free and caries-active children. Mutacin production was tested against 30 indicator strains; results showed significant variations in the inhibitory spectra of the clinical isolates. There was no association between the inhibitory spectrum of the infecting strain and the caries experience or the level of mutans streptococci infection of the host. Homology to the mutA gene coding for mutacin II was detected in one clinical isolate; none of the clinical isolates showed homology to the mutA genes coding for mutacins I or III. Genotyping by random amplified polymorphic DNA (RAPD) reactions grouped the isolates into three clusters, but no correlation was found between any of the clusters and mutacin activity, caries experience or level of mutans streptococci in the host. [source] Effects of apigenin and tt -farnesol on glucosyltransferase activity, biofilm viability and caries development in ratsMOLECULAR ORAL MICROBIOLOGY, Issue 6 2002H. Koo Propolis, a resinous hive product secreted by Apis mellifera bees, has been shown to reduce the incidence of dental caries in rats. Several compounds, mainly polyphenolics, have been identified in propolis. Apigenin and tt -farnesol demonstrated biological activity against mutans streptococci. We determined here their effects, alone or in combination, on glucosyltransferase activity, biofilm viability, and development of caries in rats. Sprague-Dawley rats were infected with Streptococcus sobrinus 6715 and treated topically twice daily as follows: (1) tt -farnesol, (2) apigenin, (3) vehicle control, (4) fluoride, (5) apigenin +tt -farnesol, and (6) chlorhexidine. Apigenin (1.33 mM) inhibited the activity of glucosyltransferases in solution (90,95%) and on the surface of saliva-coated hydroxyapatite beads (35,58%); it was devoid of antibacterial activity. tt -Farnesol (1.33 mM) showed modest antibacterial activity against biofilms and its effects on glucosyltransferases were minimal. The incidence of smooth-surface caries was significantly reduced by apigenin +tt -farnesol (60%), fluoride (70%), and chlorhexidine (72%) treatments compared to control (P < 0.05). [source] Stability and activity of specific antibodies against Streptococcus mutans and Streptococcus sobrinus in bovine milk fermented with Lactobacillus rhamnosus strain GG or treated at ultra-high temperatureMOLECULAR ORAL MICROBIOLOGY, Issue 1 2002H. Wei Passive local immunization against dental caries is a promising approach to its prevention, as clinical evidence of active oral or nasal immunization is still limited and controversial. By means of systemic immunization of pregnant cows with a multivalent vaccine, high titres of IgG antibodies against human cariogenic bacteria, Streptococcus mutans and Streptococcus sobrinus, were produced in bovine colostrum. The purified immune product (IP) of this preparation has a number of anticariogenic properties, such as inhibition of streptococcal adherence to saliva-coated hydroxyapatite and inhibition of glucosyltransferase enzymes. This study investigated whether IP antibodies remained active and functional when added to ultra-high temperature (UHT)-treated milk or to Lactobacillus rhamnosus GG (LGG)-fermented milk stored for an extended time. LGG was chosen because of its widely known health benefits in humans and animals. A commercial UHT toddler's milk was supplemented with IP and stored for 2 months at 5, 21 and 30°C. The antistreptococcal titres in UHT milk did not decline at any temperature during storage, and UHT-IP inhibited the adherence of S. mutans for up to 2 months. This was not the case with UHT toddler's milk without IgG antibodies. Milk was fermented with live LGG cells in the presence or absence of 5% IP. The antistrept?ococcal titres declined to about 30% of the original titres after storage. Fresh milk alone slightly enhanced streptococcal adhesion but fresh milk with IP inhibited the adherence of S. mutans by over 50%. LGG-positive fermented milk without antibodies also inhibited (P < 0.05) the adhesion by about 40%. In both LGG-fermented and UHT immune milk, the activity of antibodies against cariogenic streptococci was maintained during the expected shelf-life of these products. From the anticariogenic point of view it may be beneficial to add bovine-specific antibodies against mutans streptococci to probiotic LGG-containing milk products. [source] Differentiation of Streptococcus mutans and Streptococcus sobrinus via genotypic and phenotypic profiles from three different populationsMOLECULAR ORAL MICROBIOLOGY, Issue 1 2001Y. Li Routine identification of Streptococcus mutans and Streptococcus sobrinus is generally based upon growth on various selective media, colony morphology and biochemical characteristics. We examined various approaches of differentiating these two species through a combination of the conventional phenotypic methodology with chromosomal DNA fingerprint (CDF) and arbitrarily primed polymerase chain reaction (AP-PCR) methods. Initially, ten ATCC type strains and 20 randomly selected clinical isolates of mutans streptococci (MS) were characterized and grouped into two major types based on patterns generated by the CDF using HaeIII digestion. The CDF's patterns with restriction fragments equal to or greater than 6.6 kb were defined as the CDF-1 group. The CDF's patterns with restriction fragments less than 6.6 kb were defined as the CDF-2 group. Both groups were then examined for biotype, serotype, and composition of DNA via thermal denaturation. AP-PCR was applied and evaluated for the capability of delineating S. mutans from S. sobrinus strains. Results of this study showed that all CDF-1 strains fit within a G+C range of 36.2% to 42.2%, whereas the CDF-2 strains had a G+C range of 45.8% to 47.0%. The serotyping assay exhibited 100% sensitivity, 90% specificity and 86.7% agreement with the CDF. The biotyping assay presented the poorest specificity (38.5%), indicating the highest variability. The capability of AP-PCR in differentiation of S. mutans from S. sobrinus was comparable to the CDF method, suggesting that either of these two approaches can and may serve as a viable alternative method to serotyping or biotyping of MS. [source] Cariogenic Bacteria as Biomarkers for Sugar IntakeNUTRITION REVIEWS, Issue 3 2007Karin E. Vågstrand MS Cariogenic bacteria (lactobacilli and mutans streptococci) in saliva are possible biomarkers for sugar intake. We evaluated the strength of the evidence for an association between sugar intake and the two groups of bacteria, and concluded that there is a limited to moderately scientific basis for this association. Because of many confounding factors, bacteria counts can never be used as a precise measurement of sugar intake, but might still be useful on a group level. [source] Factors influencing oral colonization of mutans streptococci in young childrenAUSTRALIAN DENTAL JOURNAL, Issue 2 2007V. Law Abstract This paper aims to critically review current knowledge about the key factors involved in oral colonization of the cariogenic group of bacteria, mutans streptococci (MS) in young children. MS, consisting mainly of the species Streptococcus mutans and Streptococcus sobrinus, are commonly cultured from the mouths of infants, with prevalence of infection ranging from around 30 per cent in 3 month old predentate children to over 80 per cent in 24 month old children with primary teeth. MS is usually transmitted to children through their mothers, and the risk of transmission increases with high maternal salivary levels of MS and frequent inoculation. Factors that affect the colonization of MS may be divided into bacterial virulence, host-related and environmental factors. Complex interaction among these factors determine the success and timing of MS colonization in the child. As clinical studies have shown that caries risk is correlated with age at which initial MS colonization occurred, strategies for the prevention of dental caries should include timely control of colonization of the cariogenic bacteria in the mouths of young children. [source] Caries risk factors in the permanent dentition of Tanzanian children: a cohort study (1997,2003)COMMUNITY DENTISTRY AND ORAL EPIDEMIOLOGY, Issue 6 2007Flemming Scheutz Abstract Objective:, The aims of the cohort study were to study the association between permanent dentition caries and malnutrition and other risk factors or indicators in a group of children with little or no access to restorative and preventive dental care. Methods:, The study was conducted at two primary schools in Dar es Salaam, Tanzania in the period 1997,2003. One school recruits its children from affluent families and the other school is attended by the children of poor families. The children attended grade 1 at the first examination and had a mean age of 7.6 years (SD = 0.4); when the study was completed, the mean age was 13.3 years. Two-hundred and eighteen children examined in 1997 were re-examined in 1999; 147 of the children were examined in 1997 as well as in 2003, and 122 children were examined in all three years. An age- and sex-based body mass index (BMI) was computed to determine the nutritional status of each child. Each year, the same standard methods were used to determine the count of lactobacilli and mutans streptococci, stimulated flow rate and buffering capacity of saliva, and caries. Risk ratios were computed with generalized linear models using the tooth as the unit of analysis. Results:, Mean annual caries increment was 0.27 in the period 1997,1999 and 0.80 in the period 1999,2003 with most children developing no caries at all. Malnutrition at baseline in 1997 was insignificantly predictive for the development of caries, whereas a low stimulated flow rate of saliva (,0.7 ml/min) and a high count of lactobacilli (,100 000/ml) at baseline in 1997 were significantly associated. However, the generalized linear models for the two time periods 1997,1999 and 1999,2003 presented a confusing picture with different risk ratios and without consistency of the associations between the exposure variables and the development of caries. In accordance with this finding, the consistency of the exposure variables over time for the individuals was very low. Conclusions:, The results were inconclusive and left us with more questions than answers. The findings do, however, support the view that our methods for predicting caries are inappropriate or nonexistent. [source] Black teeth: beauty or caries prevention?COMMUNITY DENTISTRY AND ORAL EPIDEMIOLOGY, Issue 2 2006Practice, beliefs of the Kammu people Abstract , Background:, To be beautiful and caries-free, Kammu women in Laos and Vietnam habitually paint their teeth black. Although this practice existed for many generations, it is now known only among the elderly. Objectives:, To describe how the tooth-blackening procedure is performed and to test the black stain for possible antimicrobial effects in laboratory experiments. Methods:, Information on how to blacken teeth was obtained by interviewing groups of elderly Kammu people living in different villages in Laos and Vietnam. Water extracts of the stain were placed in wells in agar plates and the plates incubated with Streptococcus mutans or S. sobrinus. The stain was also let such that it covered half of the strip test-side of the Dentocult SM® Strip Mutans test kit and incubated with saliva from five persons known to carry mutans streptococci in their saliva. Results:, Interviews revealed that three plants were commonly used: Dracontomelon dao nuts (DD nuts), Cratoxylum formosum (CF) wood or Croton cascarilloides (CC) wood. The parts (nut, wood) were burned and soot collected on metal plates. The fresh soot, which had a viscous consistency, was applied to teeth with the index finger. Extracts of soot of the DD nuts had no effect on the streptococci on agar plates but inhibited the growth of salivary mutans streptococci on strips. Controls using soot from birch tree (Betula pendula) had no effect. Conclusions:, The procedure was simple and resulted in black, beautiful (?) teeth. The soot of DD nuts effectively inhibited growth of salivary mutans streptococci in in vitro experiments. [source] The complex oral microflora of high-risk individuals and groups and its role in the caries processCOMMUNITY DENTISTRY AND ORAL EPIDEMIOLOGY, Issue 4 2005David Beighton Abstract , The involvement of the oral biofilm in the caries process requires re-evaluation. The essential role of mutans streptococci (Streptococcus mutans and Streptococcus sobrinus) in the caries process is not proven. Acid production by dental plaque is not dependent upon the presence of mutans streptococci; caries occurs in the absence of these species and their presence does not necessarily indicate caries activity. Other oral bacteria, non-mutans streptococci, Actinomyces spp. and Bifidobacterium spp., are acidogenic and aciduric. They outnumber mutans streptococci in dental plaque, and there are data which support a role for these bacteria in the initiation and progression of caries. Molecular studies demonstrate the great diversity and complexity of the flora associated with caries. Many taxa identified have not been cultured and the role of these taxa is not known. We have, in mutans streptococci, good markers of disease but not necessarily the aetiological agents of the disease. Considerably more research is required to investigate the transition of tooth surfaces from being intact and sound to the white spot lesion stage. A combination of conventional and molecular approaches are required to elucidate the involvement of an individual taxon and of microbial populations with particular traits in the caries process. [source] | |||||||||||||||||||||||||