Prevalence Of Mutans Streptococci Research Articles

Prevalence of Streptococcus mutans and Candida dubliniensis in Plaque of Caries-free and Caries-active 3–6-year-old Children by Using Polymerase Chain Reaction: A Clinical Study

Prevalence of Streptococcus mutans and Candida dubliniensis in Plaque of Caries-free and Caries-active 3–6-year-old Children by Using Polymerase Chain Reaction: A Clinical Study

The Clinical Pattern and Prevalence of Streptococcus mutans and Streptococcus sobrinus among Adult and Children Patients with Dental Caries

Objective: To explore the clinical pattern, host factors, and presentation of Streptococcus mutans related to caries incidence among children and adults visiting Universitas Airlangga dental clinic. Material and Methods: This was an observational study with a cross-sectional approach with 50 patients in each group of carious children (6-12 years) and adults (18-35 years). Dental decay samples were taken by sterile excavator, put in a BHI’s transport medium, and directly incubated overnight at 37 ºC. The next day, they were sub-cultured microbiologically in Tryptone Yeast Cystine Sucrose Bacitracin (TYCSB) selective medium. Bacterial species and serogroups were examined by PCR. All patient’s data were collected from medical records and direct observation. Results: Caries were mostly media type in both children and adults. Oral hygiene (OHIS) in children was higher than in adults but not significantly different according to their DMFT. The highest scores for decay, missed and filled teeth were 16, 8 and 7, with an average of 6.82, 1.22 and 0.63, considered quite high. Conclusion: The prevalence of S. mutans was higher in children’s caries than in adults, but among the adult patients the co-incidence of S. mutans and S. sobrinus was associated with higher DMFT. The mutans serotypes e, f, and d were more prevalent among children than adults.

Determinación de Streptococcus sp. y Candida albicans en la cavidad oral de pacientes sometidos a trasplante de médula ósea

Introduction: Chemotherapy can lead to an imbalance in the ecosystem of the oral cavity, allowing the development of mucositis in the immunosuppression phase due to interaction with microbial agents. The objective of this study was to identify bacterial and fungal species that contribute to oral complications in patients undergoing marrow trans-lantation and compare their susceptibility to various antimicrobial agents before and during the immunosuppression period. Material and Methods: This observational-longitudinal study was performed on 18 patients undergoing bone marrow transplantation from the Oncohematology Ser-vice of Sanatorio Allende (2018/2019), with buccal mucosa swabs before treatment (I) and mid-stage (M), fourteen days after transplantation. The samples were cultured in selective media for Streptococcus and fungal species and a susceptibility study was performed on Müller Hinton agar. Results: At (I), 82.30% of patients were found to be positive for Streptococcus mutans, 11.30% for Streptococcus salivarius, 5.50% for Streptococcus sobrinus and 9.40% grew mixed commensal microorganisms. At (M), 96.60% were positive for Streptococcus mutans and 23.10% for Streptococcus salivarius, without any growth of Streptococcus sobrinus or mixed microorganisms. In (I), a 27.00% incidence of Candida albicans was observed, while in (M) the incidence was 73.00%. The antibiotics to which the microorganisms were most sensitive in (I) were vancomycin (88.80%), amikacin (83.30%), amoxicillin + clavulanic acid (78.00%), ciprofloxacin (77.75%) and azithromycin (66.60%). In (M) sensitivity to amikacin was 92.30%, vancomycin, 76.90%; amoxicillin + clavulanic acid, 38.50%; azithromycin, 23.10%; and ciprofloxacin, 15.40%. A statistically significant prevalence of Streptococcus mutans was observed in comparison to other species. Conclusion: During the immunosuppression period, there was a significant increase in Candida albicans. The antibiotics to which the bacteria were most sensitive were amikacin and, to a lesser extent, vancomycin, showing significant resistance to ciprofloxacin, azithromycin and amoxicillin + clavulanic acid.

The antibacterial effect of Magnolia mouthwash on the levels of salivary Streptococcus mutans in dental plaque: a randomized, single-blind, placebo-controlled trial.

Background and Objectives:Dental caries is one of the most common chronic diseases around the world. Inhibitory effects of Magnolia Grandiflora bark extract has been proved on tooth decay both in vitro and by using free sugar chewing gum. This research aimed to examine the effect of Magnolia Grandiflora bark mouth-wash on the prevalence of Streptococcus mutans in dental plaque.Materials and Methods:This crossover, placebo-controlled, clinical trial study, was performed on a total of twenty participants (aged 18 to 35 years) in both control and intervention groups and four phases. The prevalence of S. mutans was measured in a certain volume of volunteer’s dental plaque at the beginning of the project (phase 1), after the first prescription (phase 2), following the washout period (phase 3) and finally after the second prescription (phase 4) by culture on bacteriology medium. Plaque index and saliva sampling were carried out in follow-up visits by a dentist. The data were analyzed using T-Test (paired and independent) quantitatively.Results:There was a significant difference in S. mutans frequency in dental plaque between when the participants used Magnolia mouthwash and when they washed out or used a placebo (p<0.005). Results also showed a significant difference between Magnolia and Placebo groups in the mean count of saliva bacterial colony counts after oral administration in the first and second time (P<0.001 and P<0.004, respectively).Conclusion:The current trial showed that Magnolia Grandiflora %0.3 mouthwash tends to decrease the number of S. mutans in dental plaque significantly. Therefore, its mass production and release to the oral health community are suggested. However, further studies with larger sample sizes and varying treatment are required to substantiate the findings of this study.

The Queensland Birth Cohort Study for Early Childhood Caries: Results at 7 Years.

This study investigated caries predictors in 378 children remaining from a birth cohort of 1,052 at 7 y and compared the efficacy of home visits (HVs) and telephone contacts (TCs) for early childhood caries (ECC) prevention. The HVs or TCs were made at ages 6, 12, 18, 30, and 42 mo with annual dental clinic examinations at ages 2 to 7 y. At every visit, the parents completed validated questionnaires regarding the children's family, medical, dental, and dietary histories. The caries prevalence increased from 2% and 6% at ages 2 and 3 y to 15%, 33%, 42%, and 52% at ages 4 to 7 y. The mean caries experience (decayed, missing, and teeth extracted due to caries) of the total cohort increased from 0.1 ± 0.5 at age 2 y to 0.2 ± 1.1 at 3 y, 0.5 ± 1.6 at 4 y, 1.1 ± 2.4 at 5 y, 1.6 ± 2.6 at 6 y, and 2.0 ± 2.7 at 7 y. The prevalence of mutans streptococci (MS) in the total cohort at years 2 to 7 was 22%, 36%, 42%, 42%, 39%, and 44%, respectively. MS was strongly correlated with caries prevalence for all years (all P < 0.001). Statistical modeling employing the generalized estimating equations identified caries predictors as holding a Health Care Card (low socioeconomic status) (P = 0.009; odds ratio [OR] = 2.05; confidence interval [CI]: 1.20-3.52), developmental defects of enamel (DDEs) (P < 0.001; OR = 1.09; CI: 1.05-1.14), and MS counts ≤105/mL (P = 0.001; OR = 1.63; CI: 1.24-2.14). By contrast, HVs were more protective than TCs for caries (P = 0.008; OR = 0.42; CI: 0.22-0.80). This study provides prospective, clinical evidence that MS, DDEs, and low socioeconomic status are strongly correlated with early childhood caries and that HVs are more efficacious than TCs in ECC prevention. This 7-y birth cohort study provides longitudinal clinical evidence that mutans streptococci, developmental defects of enamel, and low socioeconomic status are key risk indicators of early childhood caries.

Molecular and serological typing of Streptococcus mutans strains isolated from young Galician population: relationship with the oral health status.

The aim of this study was to determine the prevalence of Streptococcus mutans and its serotypes in samples from oral cavity of young Galician population and their relationship with the oral health state. The variables generally associated with dental caries, such as salivary flow rate, buffering capacity, eating habits, and lifestyle, were also analysed. No relationship was found between the variables studied and the presence of S. mutans in the oral cavity or the existence of dental caries. Presumptive strains of S. mutans were isolated from saliva samples from 48% of the analysed population. The use of conventional microbiological methods, API 20 Strep system, and species-specific polymerase chain reaction (PCR) allowed to substantiate the identity of the strains as S. mutans. Multiplex PCR protocols, developed in this study for the simultaneous detection of S. mutans and serotypes c, e, and f andfor detection ofS. mutans and serotype k, also confirmed this result and demonstrated that serotype c was predominant in the studied young Galician population (86%). Serotypes e (8%), k (3%), and f (2%) were also detected. Serotype c was detected in carious and caries-free subjects, while the remaining serotypes were only found in subjects with caries.

The Prevalence of Streptococcus Mutans with Different ABO Blood Groups Among Healthy College Students

Objective:This study was conducted to determine the correlation between the occurrence ofStreptococcus mutans(S. mutans) which is considered as the main pathogen responsible for the initiation and development of dental caries with blood groups and Rhesus (Rh) factor that are considered as a genetic predictor of having dental caries among healthy students.Methods:Saliva and blood samples were taken from 40 healthy students whose ages were between 19-23 years old in the College of Dentistry/Al-Iraqia University in Baghdad, Iraq. Estimation of the flow rate and pH was done for all the collected saliva samples within 5 min of saliva collection. Then, 100 µL of saliva was cultured on Mitis salivarius bacitracin agar (MSBA) at 37 °C for 48 h. The colonies ofS. mutanswere identified by their morphology and biochemical tests. Later, 1 to 2 drops of blood were taken from each student’s thumb to determine the blood group.Results:This study showed there was a greater prevalence ofS. mutansamong students of blood group A in contrast to the blood group O. In addition, Rh+ groups were dominant than Rh- groups among the study samples.Conclusion:S. mutanslevels were higher in the blood group A followed by AB, B, O blood groups among the college students studied.

Microorganisms related to early childhood caries in a sample of an oral preventive-educative program: a longitudinal study

Objetivo: Premature acquisition of cariogenic microorganisms seems to be related to higher prevalence and activity of caries lesions. The aim of the study was to evaluate the prevalence of Streptococcus mutans and Streptococcus sobrinus in infants enrolled in a dental preventive program and in their mothers, as well as to assess the influence of bacterial prevalence, diet and oral hygiene in dental caries prevalence. Material and Methods: After clinical examinations (n = 50), saliva and oral biofilms were collected and stored prior to real-time PCR at 6, 12, 18 and 24 months of age. Results: No correlation was observed between the presence of cariogenic pathogens and diet or hygiene habits at all ages; however, association increased with number of erupted teeth. Salivary levels of bacteria were lower in children than in their mothers at all ages, and children with carious lesions had high ingestion of sugared food. Conclusion: As the levels of cariogenic pathogens were low in the patients that were enrolled in a preventive program, we can conclude that control of oral biofilm as eruption of infants’ teeth occurs and sugar ingestion should be considered of great importance in preventive dentistry, because the association between them was highly positive.KeywordsSaliva; Dental caries; Oral hygiene; Cariogenic; Streptococcus mutans.

Streptococcus mutans Dental Caries among Patients Attending Debre Berhan Referral Hospital, Ethiopia

Background: Dental caries is an irreversible microbial disease of the calcified tissues of the teeth. Streptococcus mutans is a bacterial resident of the oral cavity and is considered to be the principal etiological agent of dental caries in humans. Therefore, the aim of this study was to determine the prevalence and risk factors associated with Streptococcus mutans dental caries. Methods: A cross sectional study was conducted among patients who attended Debre Berhan referral hospital dental clinic. Patient’s demographic and clinical information was collected by using pre-tested questionnaire. Dental plaques from all patients was picked up by forceps and suspended in to phosphate-buffered saline for further Streptococcus mutans identification. Result: From a total of 115 study participants 56 (48.7%) and 59 (51.3%) were males and females respectively. The overall prevalence of Streptococcus mutans was 79 (68.7%) among patients with dental caries. participants 25 (21.7%) had gem bleeding and 47 (40.9%) of the participants had previous tooth decay. Conclusion: In this study, again Streptococcus mutans is the common public health problem among dental caries patients. Drinking soft drinks, oral debris and gingival index were the associated risk factor for dental caries of Streptococcus mutans.

Genotypic diversity and phenotypic traits of Streptococcus mutans isolates and their relation to severity of early childhood caries

BackgroundEarly childhood caries (ECC) is an aggressive condition that can affect teeth of young children. This study aimed to evaluate genotypic diversity and phenotypic traits of S. mutans isolated from dental biofilms of children with different caries status in comparison with caries free (CF) children.MethodsStreptococcus mutans strains were isolated from supragingival biofilm samples of CF, ECC and severe-ECC (S-ECC) children and genotyped by arbitrary-primer polymerase chain reaction - AP-PCR. S. mutans genotypes were tested for their ability to reduce the suspension pH through glycolysis, to tolerate extreme acid challenge and by their ability to form biofilm. Response variables were analyzed by ANOVA/Tukey or Kruskal-Wallis/Mann-Whitney tests at a 5% of significance.ResultsThere was an increase in the prevalence of Streptococcus mutans in biofilms with the severity of dental caries. No differences in genotypic diversity and in acidogenicity of genotypes were found among CF, ECC and S-ECC children. S mutans strains with genotypes more characteristic for ECC and S-ECC children formed more biofilms than those identified in CF children. The strains isolated from S-ECC children were highly acid tolerant.ConclusionAlthough S. mutans genotypic diversity was similar among the groups of children, phenotypic traits of S. mutans, especially the acid tolerance response, could explain the severity of early childhood caries.

Correlation of Streptococcus mutans count in Mother-child Pair of Working and Nonworking Mothers: A Cross-sectional Study.

PurposeTo determine the prevalence of Streptococcus mutans (MS) in mother-child pairs and to evaluate the correlation in the levels of salivary MS of working and nonworking mothers with that of their children and their associations with other related factors.Materials and methodsA cross-sectional study was carried out among 100 mother-child pairs residing in New Multan Nagar Colony, New Delhi, India. A total of 50 children with their mothers were included in the working group and another 50 were included in the nonworking group. A questionnaire regarding the feeding habits, oral hygiene habits, daily intake of sugars of the children along with their weaning time was carried out. All mothers and children were clinically examined for recording decayed, extracted, and filled teeth (deft)/decayed, missing, and filled teeth (DMFT), and whole unstimulated saliva was collected and cultured for MS in the laboratory. The data were collected and subjected to statistical analysis using chi-square, Spearman’s correlation, and logistic regression analysis.ResultsThe prevalence of salivary MS in the children was 69%. A statistically significant correlation was found between the oral levels of MS in nonworking and working mother-child pairs. Regression analysis showed that those children who feed by bottle for more than 12 months, have daily sweet intake, have sugars in feeding bottle and have higher defts were more likely to have mutans score of 1 or 2.ConclusionThe mother, working or nonworking, being the primary care provider is the major source of transmission of MS to their child irrespective of the amount of time spent with them.How to cite this articleSharma P, Goswami M, Singh D, Massod SS, Nganba K. Correlation of Streptococcus mutans count in Mother-child Pair of Working and Nonworking Mothers: A Cross-sectional Study. Int J Clin Pediatr Dent 2016;9(4):342-348.

Streptococcus mutans and Lactobacillus Species Infection in Obese and Non-Obese School Children in Accra, Ghana

Introduction Several bacteria colonize the oral cavity. Some are involved in oral diseases including dental caries. Dental caries is one of the commonest oral problems in children [1]. Acid producing oral bacteria such as Streptococcus mutans and Lactobacillus species are the major bacteria associated with caries [2]. For a long time it was thought that the presence of these bacteria alone may lead to dental caries but later studies have demonstrated that there were cases where caries occurred even in the absence of these bacteria [3,4]. Some of these other bacteria include Streptococcus sanguinis, Streptococcus oralis, Neisseria subflava. However, when Streptococcus mutans and Lactobacillus species dominate the plaque caries occurs faster [2,3]. Colonization by some of the oral bacterial starts even before the eruption of teeth in the mouth of children [5]. These bacteria are thought to be transmitted from mother to child [6-9]. Background: Streptococcus mutans and Lactobacillus species are major bacteria associated with dental caries. In the presence of fermentable sugars and poor oral hygiene these bacteria increase risk of caries. Some studies have associated obesity with dental caries while others did not. High sugar snacks are risks for both obesity and dental caries. Citation: Ndanu TA, Aryeetey R, Sackeyfio J, Otoo G, Lartey A, et al. (2015) Streptococcus Mutans and Lactobacillus Species Infection in Obese and Non-Obese School Children in Accra, Ghana. J Obes Overweig 1(1): 101 Objectives: This study aimed at determining Streptococcus mutans and Lactobacillus species infection and its relationship with dental caries among obese and non-obese children. Methods: Oral plaque was taken from 75 each of obese and non-obese children from private schools in Accra, Ghana. The plaque was pre-enriched in thioglycollate broth for 48 hours at 37 °C. Streptococcus mutans and Lactobacillus species were recovered after sub-culturing the broths onto Mitis Salivarius Bacitracin (MSB) and Man Rogosa Sharpe (MRS) selective plates, respectively, and incubation at 37 °C under anaerobic conditions. Bacteria isolates on the selective plates were identified using Gram morphology and catalase activity. Results: Streptococcus mutans was isolated in 51 (33.6%) of all 150 children. The prevalence of Streptococcus mutans was significantly higher in the obese children 31 (41.3%) than the non-obese 20 (26.0%), p=0.033. Recovery of Lactobacillus species was low 2 (1.3%). Caries prevalence was similar in the obese 14.9% and non-obese 15.1%. There was no significant association between Streptococcus mutans infection and the dental caries. Overall Silness and LOe Plaque Index of 1.1 ± 0.5 indicate good oral hygiene status for the children. Conclusion: Obese school children had higher oral Streptococcus mutans infections than non-obese children but this was not significantly associated with dental caries prevalence.

Can insoluble polysaccharide concentration in dental plaque, sugar exposure and cariogenic microorganisms predict early childhood caries? A follow-up study

BackgroundInsoluble polysaccharide (IP) has been associated with caries prevalence in young children. However, the power of IP to predict ECC needs to be demonstrated. AimsTo assess the relationships between early childhood caries (ECC) and extracellular insoluble polysaccharides (IP) in dental plaque, sugar exposure and cariogenic microorganisms. DesignVisible plaque on maxillary incisors was recorded, followed by caries diagnosis in 65 preschoolers (3–4 years) at baseline and after 1 year. Plaque was collected for mutans streptococci (MS), total microorganism (TM) and lactobacilli (LB) enumerations in selective media, as well as for IP analysis, which was later assessed by colorimetry. Sugar/sucrose exposure was assessed by a diet chart. ResultsPositive correlations were found among the prevalence of caries and MS, TM, LB, solid sucrose and visible dental plaque. Additionally, children with IP concentrations in dental plaque higher than 2.36μg/mg (odds ratio-OR=6.8), with visible plaque on maxillary incisors (OR=4.3), harbouring LB (OR=13) and exposed to solid sugar more than twice/day (OR=5) showed higher risk of developing caries (p<0.05). ConclusionExtracellular insoluble polysaccharides, solid sugar/sucrose, visible dental plaque and cariogenic microorganisms could predict caries development, partially explaining the ECC pattern.

Chlorhexidine treatment for the prevention of dental caries in children and adolescents.

Dental caries (tooth decay) is a common disease that is preventable by reducing the dietary intake of free sugars and using topical sodium fluoride products. An antibacterial agent known as chlorhexidine may also help prevent caries. A number of over-the-counter and professionally administered chlorhexidine-based preparations are available in a variety of formulations and in a range of strengths. Although previous reviews have concluded that some formulations of chlorhexidine may be effective in inhibiting the progression of established caries in children, there is currently a lack of evidence to either claim or refute a benefit for its use in preventing dental caries. To assess the effects of chlorhexidine-containing oral products (toothpastes, mouthrinses, varnishes, gels, gums and sprays) on the prevention of dental caries in children and adolescents. We searched the Cochrane Oral Health Group Trials Register (25 February 2015), the Cochrane Central Register of Controlled Trials (CENTRAL; 2014, Issue 12), MEDLINE via OVID (1946 to 25 February 2015), EMBASE via OVID (1980 to 25 February 2015) and CINAHL via EBSCO (1937 to 25 February 2015). We handsearched several journals placed no language restrictions on our search. After duplicate citations were removed, the electronic searches retrieved 1075 references to studies. We included parallel-group, randomised controlled trials (RCTs) that compared the caries preventive effects of chlorhexidine gels, toothpastes, varnishes, mouthrinses, chewing gums or sprays with each other, placebo or no intervention in children and adolescents. We excluded trials with combined interventions of chlorhexidine and fluoride or comparisons between chlorhexidine and fluoride interventions. Two review authors independently extracted trial data and assessed risk of bias. We resolved disagreements by consensus. We contacted trial authors for clarification or additional study details when necessary. The number of included studies that were suitable for meta-analysis was limited due to the clinical diversity of the included studies with respect to age, composition of intervention, and variation in outcome measures and follow-up. Where we were unable to conduct meta-analysis, we elected to present a narrative synthesis of the results. We included eight RCTs that evaluated the effects of chlorhexidine varnishes (1%, 10% or 40% concentration) and chlorhexidine gel (0.12%) on the primary or permanent teeth, or both, of children from birth to 15 years of age at the start of the study. The studies randomised a total of 2876 participants, of whom 2276 (79%) were evaluated. We assessed six studies as being at high risk of bias overall and two studies as being at unclear risk of bias overall. Follow-up assessment ranged from 6 to 36 months.Six trials compared chlorhexidine varnish with placebo or no treatment. It was possible to pool the data from two trials in the permanent dentition (one study using 10% chlorhexidine and the other, 40%). This led to an increase in the DMFS increment in the varnish group of 0.53 (95% confidence interval (CI) -0.47 to 1.53; two trials, 690 participants; very low quality evidence). Only one trial (10% concentration chlorhexidine varnish) provided usable data for elevated mutans streptococci levels > 4 with RR 0.93 (95% CI 0.80 to 1.07, 496 participants; very low quality evidence). One trial measured adverse effects (for example, ulcers or tooth staining) and reported that there were none; another trial reported that no side effects of the treatment were noted. No trials reported on pain, quality of life, patient satisfaction or costs.Two trials compared chlorhexidine gel (0.12% concentration) with no treatment in the primary dentition. The presence of new caries gave rise to a 95% confidence interval that was compatible with either an increase or a decrease in caries incidence (RR 1.00, 95% CI 0.36 to 2.77; 487 participants; very low quality evidence). Similarly, data for the effects of chlorhexidine gel on the prevalence of mutans streptococci were inconclusive (RR 1.26, 95% CI 0.95 to 1.66; two trials, 490 participants; very low quality evidence). Both trials measured adverse effects and did not observe any. Neither of these trials reported on the other secondary outcomes such as measures of pain, quality of life, patient satisfaction or direct and indirect costs of interventions. We found little evidence from the eight trials on varnishes and gels included in this review to either support or refute the assertion that chlorhexidine is more effective than placebo or no treatment in the prevention of caries or the reduction of mutans streptococci levels in children and adolescents. There were no trials on other products containing chlorhexidine such as sprays, toothpastes, chewing gums or mouthrinses. Further high quality research is required, in particular evaluating the effects on both the primary and permanent dentition and using other chlorhexidine-containing oral products.

Correlation between mutans streptococci counts of parents and their children residing in Chandigarh, India.

Objectives: To determine the prevalence of Mutans Streptococci (MS) in children and to evaluate the relationship between the salivary levels of MS in children and their parents. Material and Methods: 100 children aged 3-6 years along with their parents (100 mothers and fathers each) were included in the study. The children were segregated depending upon their age and level of caries experience. The children were examined clinically on an ordinary chair in natural daylight using the Møller’s index criteria. Assays for Mutans Streptococci (MS) were done for both the children and their parents using the Dentocult SM strip mutans test. Collected data was assessed using SPSS software. Results: The overall prevalence of MS in the children was 83%. A statistically significant correlation (p<0.05) was observed between salivary MS counts of children and their mothers. No significant correlation was seen with the fathers. Conclusions: The findings conclude that if primary caregivers harbour high levels of MS in their saliva, it is likely that their children will have the same. Key words:Mutans streptococci, parents, children, dentocult SM kits.

Serotype specific polymerase chain reaction identifies a higher prevalence of streptococcus mutans serotype k and e in a random group of children with dental caries from the Southern region of India.

Background:The development of dental caries has been associated with the oral prevalence of Streptococcus mutans. Four serotypes of S. mutans have been reported, namely serotype c, e, f, and k that are classified based on the composition and linkages of cell wall polysaccharides, response to physiological reactions, sero-specificity and 16s rRNA homology. Although the oral prevalence of S. mutans serotype c in Indian subjects with or without caries is known, the prevalence of the other three serotypes, e, f, and k are not known. Hence in this study, we have investigated the occurrence of the e, f, and k serotypes in children with or without caries within the age group of 6-12 years.Materials and Methods:Genomic DNA isolated from whole saliva of caries active (CA) and caries free (CF) groups were first screened for the presence of S. mutans by strain specific polymerase chain reaction (PCR). Those samples that tested positive for the presence of S. mutans were further analyzed by serotype specific PCR to identify the prevalence of the serotypes.Results:Strain specific PCR indicated a higher prevalence of S. mutans in CA group (80%) relative to CF group (43%). Further analysis of the S. mutans positive samples in both groups indicated a higher prevalence of serotype k and e, followed by serotype f in CA group.Conclusion:The present data clearly establishes a novel S. mutans serotype prevalence hierarchy in children from this region, compared with those that have been reported elsewhere. Besides, the data are also clinically significant as the occurrence of serotype k has been associated with infective endocarditis.

Prevalence of dental erosion and association with lifestyle factors in Swedish 20-year olds

Objective. To investigate the prevalence, distribution and severity of dental erosion and its association with lifestyle, oral and general health in young adults. Materials and methods. Four hundred and ninety-four individuals, 20-years of age, participated. Dental erosion in molars and maxillary incisors was evaluated. Caries, plaque and gingivitis were registered. Saliva samples were taken and the subjects were interviewed about behavioural and dietary habits and oral and general health. Body mass index (BMI) was calculated. The individuals were sub-divided into two groups according to the presence and absence of dental erosion: within the group with erosion was a sub-group of individuals with extensive erosion. Results. Of the individuals 25% had no erosion, 75% had erosion and 18% had extensive erosion. Erosion was found in molars in 74% of the individuals and on buccal and palatal surfaces in maxillary incisors in 4% and 7%, respectively. Cupping was seen in 65% of individuals and severe erosion in molars in 1.6%. Compared to subjects with no erosion, those with extensive erosion had a higher consumption of soft drinks (p = 0.05), caries prevalence (p < 0.01), prevalence of mutans Streptococci (p < 0.01) and BMI (p < 0.05). Furthermore, subjects with erosion had higher caries prevalence (p < 0.01) and BMI (p < 0.01) than those with no erosion. Conclusions. Swedish young adults have a high prevalence of dental erosion, but the level of severe erosion is low. The study disclosed a relationship between dental erosion and behavioural factors, oral health and BMI.

Bacterial colonization, enamel defects and dental caries in 4-6-year-old mono- and dizygotic twins

Knowledge of the genetic and environmental influences in caries aetiology has relevance for preventive dentistry. This classical twin study compared concordance of mutans streptococci (MS) and lactobacilli (LB) colonization, enamel defects, and caries in a cohort of 4-6-year-old mono- (MZ) and dizygotic (DZ) twin pairs. The twins were examined for prevalence and concordance of enamel opacities and hypoplasia, oral counts of MS and LB, and dental caries. Bacterial counts were assessed using a commercial microbiological kit. Thirty-four MZ and 50 DZ twins (mean gestational age 35.0 ± 2.4 weeks, and birthweight 2.4 ± 0.6 kg) were examined. There were no statistically significant differences between MZ and DZ twins in the prevalence of MS, LB, and enamel hypoplasia. Concordance rates for MS and LB presence and prevalence of enamel defects within MZ and DZ twin pairs were not significantly different. There were more children with caries in DZ compared with MZ twins (18% vs 3%, P = 0.0029), most likely due to increased daily frequency of sugar consumption and less toothbrushing. Concordance data from MZ and DZ twins did not demonstrate any statistically significant difference in susceptibility for enamel defects and colonization of MS and LB.

Prevalence of Streptococcus mutans and Lactobacillus fermentum and their association with caries and dietary habits in preschool Thai children

To detect the prevalence of Streptococcus mutans and Lactobacillus fermentum in plaque obtained from severe early childhood caries (S-ECC) and caries-free (CF) groups and to assess any association between their prevalence, feeding habits and oral hygiene practices within each group. Sixty-four supra-gingival plaque samples were collected from S-ECC and CF groups (CF=30, S-ECC=34). All participants were asked about feeding habits and oral hygiene care behaviour by direct questionnaire. After DNA extraction, S. mutans and L. fermentum were amplified using standard PCR. Nested PCR was performed as a second identification method for S. mutans. Mean age in CF and S-ECC was 2.29±0.42 and 2.49±0.41years, respectively. Mean dmft in S-ECC was 4.51±0.72. By standard PCR, no S. mutans was detected in CF group, while 10% was detected in S-ECC group. By nested PCR, S. mutans was detected for 48 and 50% in CF and S-ECC, respectively. L. fermentum was detected for 16 and 40% in CF and S-ECC, respectively. Nested PCR gave a higher detection frequency than standard PCR but not significant (p≤0.05). The prevalence of S. mutans was not different between the two groups, while the prevalence of L. fermentum was significantly associated with S-ECC (p≤0.05).

Streptococcus mutans and Streptococcus sobrinus detection by Polymerase Chain Reaction and their relation to dental caries in 12 and 15 year-old schoolchildren in Valencia (Spain)

A cross-sectional study was carried out to determine the prevalence of Streptococcus mutans and Streptococcus sobrinus and the association of the two in a random sample (n=614) of the child population of the region of Valencia (Spain). Saliva samples were analyzed by the quantitative polymerase chain reaction (PCR) method to study the relation of these bacteria to caries prevalence and the DMFT index. The prevalence of S. mutans was 35.4% at age 12 and 22.9% at age 15, that of S. sobrinus 18.9% and 8.4% and that of the S. mutans-S. sobrinus association 18.2% and 6.8% respectively. At both 12 and 15 years of age, the caries prevalence rates were lower in the Streptococcus-free group of children (37.6% and 48.5% respectively) and higher in the S.mutans-only group (67.3% and 74.0%). At the age of 12, the DMFT index was significantly higher in the mutans-only carriers (2.1) than in the Streptococcus-free and S. mutans-S. sobrinus association groups (both 0.9). At the age of 15, the DMFT index was significantly higher in the S. mutans-S. sobrinus association (3.71) and mutans-only (3.1) carrier groups than in the Streptococcus-free group (1.4). Determination of S. mutans and S. sobrinus by real-time quantitative PCR can provide valuable information for caries risk assessment in epidemiological studies. Key words:Streptococcus mutans, Streptococcus sobrinus, polymerase chain reaction, dental caries, cross-sectional studies.