Cariogenic Potential Research Articles

Evaluation of Sugar Content and Erosive Potential of the Commonly Prescribed Liquid Oral Medications

Objective: To assess the total sugar content, endogenous pH, total soluble solids content (TSSC) and titratable acidity of the commonly prescribed long-term and short-term liquid oral medicines (LOM) for children and to compare the erosive potential with the total sugar content and total soluble solids of the LOM. Material and Methods: Twenty-three most commonly prescribed pediatric LOM were evaluated in-vitro for the cariogenic and erosive potential. Manufacturers' information on labels, endogenous pH, titratable acidity, TSSC, and the total sugar content was determined. Descriptive statistics and the Mann-Whitney U test were applied. Results: Overall, 22 LOM contained sugar. Only 3 LOM revealed the sugar content of the formulation but did not disclose the quantity (Cheston, Ventorlin and Eptoin). None of the samples revealed the sugar content as well as endogenous pH in their labels. The overall mean total sugar content was 6.92 ± 3.49 g/100ml, ranging from 3.40 ± 0.00 (corticosteroids) to 9.67 ± 0.61 (antitussive/expectorant). The mean endogenous pH for the total sample of medicines was 5.91 ± 1.51 (range of 3.5 to 10.3). Eptoin (0.013%) presented the lowest titratable acidity and Imol (1.171%) presented the highest titratable acidity with an overall mean of 0.40 ± 0.73. Omnacortil and Epilex presented the highest TSS content (19.3%), and Ventorlin presented the lowest TSS content (18.7%) with an overall mean of 18.97 ± 0.19. Over twelve medicines were identified to have the potential to cause dental erosion. No significant differences were seen in the total sugar content, total soluble solids, titratable acidity, and the endogenous pH between the short-term and long-term LOMs (p=0.145, p=0.263, p=0.067 and p=0.107), respectively. Conclusion: The pediatric LOMs showed the presence of the sugar, low endogenous pH, high titratable acidity and high total soluble solids.

Chapter 8: Milk, Yoghurts and Dental Caries.

Milk is an important part of the human diet; after weaning, cow's milk (bovine milk) predominates and this chapter considers the effect of bovine milk on dental caries. Yoghurt, which is a milk product, is also considered here. Several published reviews have concluded that milk is of very low cariogenicity and may have some caries protective potential. For example, WHO reviewed the strength of the evidence in 2003 and concluded that a "decreased risk" of dental caries from milk was "possible." The evidence comes from several types of study: epidemiological studies (interventional and observational), animal experiments, plaque pH studies, and in vivo and in vitro enamel and dentine slab experiments. More recent observational epidemiological studies have adjusted for potential confounders and have reported that milk consumption is associated with lower caries experience or incidence. Other types of study generally support this conclusion. Reasons for these favourable caries-related properties include the lower acidogenicity of lactose compared with other dietary sugars and the protective effects of calcium, phosphate, proteins, and fats. There is less research concerning yoghurts but it is likely that the cariogenic potential of plain yoghurt is similar to that of milk. The addition of sucrose to milk increases caries risk.

PH dependent effects of sodium ions on dextransucrase activity in Streptococcus mutans

Dextransuccrase (E.C 2.4.1.5) is a key enzyme in S. mutans for the metabolism of sucrose which helps in the adherence and accumulation of bacteria on tooth surface leading to the formation of dental caries. Dextransuccrase resembles in its catalytic properties with the brush boarder sucrase and exhibits pH dependent inhibitory and stimulatory effects in response to Na+. In this communication we studied the effect of monovalent cations on the activity of dextransuccrase from S. mutans. The percentage inhibition of dextransuccrase was 65% at 0.5 mM NaCl which enhanced to 90% at 20 mM sodium concentration. However there was no effect on dextransucrase activity in presence of other monovalent cations (Rb+, Cs+, and K+) tested. Enzyme activity was enhanced 20–24% in acidic pH but was strongly inhibited (59–89%) around neutral and alkaline pH by 0.5–2.0 mM sodium chloride. Upon dialysis, 86% of enzyme activity was restored to control values. There was no effect of 2 mM NaCl on glucosyltransferase activity of the enzyme. Kinetic studies revealed that enzyme showed biphasic effects in response to Na+ ions. At acidic pH the enzyme exhibited mixed type of activation affecting both Vmax and Km, while in alkaline pH, the enzyme showed V- type effect reducing Vmax by 74% without affecting Km. The effects of sodium ions on dextransuccrase activity were specific, thus it can be useful to block its catalytic activity, and reducing the cariogenic potential of S. mutans.

Conserved Pheromone Production, Response and Degradation by Streptococcus mutans.

Streptococcus mutans, a bacterium with high cariogenic potential, coordinates competence for natural transformation and bacteriocin production via the XIP and CSP pheromones. CSP is effective in inducing bacteriocin responses but not competence in chemically defined media (CDM). This is in contrast to XIP, which is a strong inducer of competence in CDM but can also stimulate bacteriocin genes as a late response. Interconnections between the pathways activated by the two pheromones have been characterized in certain detail in S. mutans UA159, but it is mostly unknown whether such findings are representative for the species. In this study, we used bioassays based on luciferase reporters for the bacteriocin gene cipB and the alternative sigma factor sigX to investigate various S. mutans isolates for production and response to CSP and XIP pheromones in CDM. Similar to S. mutans UA159, endogenous CSP was undetectable in the culture supernatants of all tested strains. During optimization of the bioassay using the cipB reporter, we discovered that the activity of exogenous CSP used as a standard was reduced over time during S. mutans growth. Using a FRET-CSP reporter peptide, we found that S. mutans UA159 was able to degrade CSP, and that such activity was not significantly different in isogenic mutants with deletion of the protease gene htrA or the competence genes sigX, oppD, and comR. CSP cleavage was also detected in all the wild type strains, indicating that this is a conserved feature in S. mutans. For the XIP pheromone, endogenous production was observed in the supernatants of all 34 tested strains at peak concentrations in culture supernatants that varied between 200 and 26000 nM. Transformation in the presence of exogenous XIP was detected in all but one of the isolates. The efficiency of transformation varied, however, among the different strains, and for those with the highest transformation rates, endogenous XIP peak concentrations in the supernatants were above 2000 nM XIP. We conclude that XIP production and inducing effect on transformation, as well as the ability to degrade CSP, are conserved functions among different S. mutans isolates. Understanding the functionality and conservation of pheromone systems in S. mutans may lead to novel strategies to prevent or treat unbalances in oral microbiomes that may favor diseases.

Analysis of cariogenic potential of alternative milk beverages by in vitro Streptococcus mutans biofilm model and ex vivo caries model

ObjectiveTo evaluate the potential of various alternative milk beverages to support bacterial biofilm formation and acid production and cause unbalanced demineralization. Designin vitro assays were used to examine the ability of the beverages to support Streptococcus mutans’ biofilm formation and acid production from sugar fermentation and the capacity of the beverages to buffer pH changes. Biofilm formation was done using 96-well plate model. Acid production was measured using L-Lactate assay kit, and the buffering capacity was assessed by pH titration. For ex vivo caries model, enamel and dentine slabs and S. mutans biofilms were exposed to selected alternative milk beverages three times a day, 30 min each, and by the end of the experiments, slab’s demineralization was assessed by loss of surface microhardness. ResultsOf the alternative milk beverages tested in this study, Original Almond consistently supported the most S. mutans biofilms, followed by Chocolate Cashew Milk, while the least biofilms were measured with Unsweetened Flax Milk. The most acids and the lowest culture pH were measured with Toasted Coconut Almond Milk, while the least buffering capacity was measured with Unsweetened Coconut Milk. The results of ex vivo caries model showed that like Bovine Whole Milk, repeated exposure to Original Almond led to significant enamel and dentine slab demineralization, when compared to those exposed to saline as a control (P < 0.001). ConclusionsThese results further provide support that popular alternative milk beverages, especially those with supplemental sugars, are potentially cariogenic.

Acidogenic Potential of Oral Bifidobacterium and Its High Fluoride Tolerance.

Bifidobacterium is frequently detected in early childhood caries and white spot lesions, indicating that it is a novel caries-associated bacterium. Bifidobacterium is known to possess a unique metabolic pathway, the “bifid shunt,” which might give it cariogenic potential by increasing its acid production. Thus, we evaluated the acid-producing activity of Bifidobacterium and its sensitivity to fluoride, a caries preventive reagent. Bifidobacterium longum, Bifidobacterium dentium, and Streptococcus mutans were used. Acid-producing activity was measured using a pH-stat in the absence and presence of fluoride under anaerobic conditions. Furthermore, metabolomic analysis was performed to elucidate the mechanism underlying the inhibitory effects of fluoride. The acid production of Bifidobacterium at pH 5.5 was as high as that seen at pH 7.0, indicating that Bifidobacterium has high cariogenic potential, although it produced less acid than S. mutans. In addition, Bifidobacterium produced acid in the absence of extracellular carbohydrates, suggesting that it can store intracellular polysaccharides. Bifidobacterium produced more acid from lactose than from glucose. Bifidobacterium mainly produced acetate, whereas S. mutans mainly produced lactate. The 50% inhibitory concentration (IC50) of fluoride for acid production was 6.0–14.2 times higher in Bifidobacterium than in S. mutans. Fluoride inhibited enolase in the glycolysis, resulting in the intracellular accumulation of 3-phosphoenolpyruvate, glucose 6-phosphate, and erythrose 4-phosphate. However, the bifid shunt provides a bypass pathway that can be used to produce acetate, suggesting that Bifidobacterium is able to metabolize carbohydrates in the presence of fluoride. It is suggested that its exclusive acetate production contributes to the pathogenesis of dental caries.

In vitro evaluation of the cariogenic potential of rebaudioside A compared to sucrose and xylitol.

The aim of the present study was to evaluate the growth and acid synthesis of cariogenic pathogens in vitro when rebaudioside A was the sole source of carbon, compared to sucrose, xylitol, and a commercial sweetener containing rebaudioside A. First, sucrose or sugar substitutes were added to human saliva and the pH was measured over 10h. Subsequently, the growth and acid synthesis efficiency of Streptococcus mutans, Streptococcus sobrinus, Streptococcus oralis, Lactobacillus rhamnosus, Lactobacillus paracasei, and Candida albicans were investigated: after adding them to minimal culture media containing only one of the carbon sources, the optical density and pH were determined over 10h. A significant pH drop only occurred in the sucrose group of human saliva whereas no differences were found between the sugar substitute groups. The individual strains of caries pathogens showed significantly lower growth rates and less acid synthesis in the sugar replacement groups, in comparison to sucrose. However, these groups also showed bacterial growth and a decline in pH. Xylitol appeared to be superior to rebaudioside A regarding the inhibition of mutans streptococci. The results for the remaining microorganisms indicate that rebaudioside A causes a similar or lower acid synthesis than xylitol. As saliva contains buffer systems, the metabolism of rebaudioside A did not seem to shift the equilibrium to demineralization. Rebaudioside A may not be suitable as a targeted Streptococcus mutans treatment, but it could contribute to a reduction of caries risk as a replacement for sucrose.

Influence of fluoride and/or bovine albumin and some common beverages on electrochemical properties of ionic liquid coated Zirconium for enhancing dental implantology performance

Myriads of materials have been used for dental replacement. The success of these materials relies on the ability to accommodate with the host oral cavity which provides an ideal and unique environment for study of biological processes involving metallic dental aids. Indeed, the essential acids and sugars in beverages have both acidogenic and cariogenic potential, resulting in dental corrosion. In this regard, a new approach for corrosion protection of Zirconium surface coated with 1-Butyl-3-methylimidazolium chloride ionic liquid ([Bmim]Cl) IL was investigated in artificial saliva containing fluoride and/or albumin, and some corrosive beverages. The morphology and composition of the ([Bmim]Cl) IL produced coat was characterized by means of scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy (SEM-EDX). The cyclic voltammetry and impedance spectra were recorded and the equivalent electric circuits were developed. The tafel slopes were noted from the linear polarization, and the corrosion parameters were calculated for bare and coated Zirconium. All results sustained the corrosion resistance enhancement for coated Zr, which ascribed to the beneficial effect of the adherent passive film caused by the thermal breakdown of IL molecules and the consequent adsorption of the Imidazolium molecule by planar configuration on Zr surface. Furthermore, computational chemistry modeling was used to understand the adsorption and corrosion inhibition performance for the IL on metal surface interface, and the results come in strong agreement with the experimental study.

Role of Candida albicans on enamel demineralization and on acidogenic potential of Streptococcus mutans in vitro biofilms.

There is growing evidence that C. albicans is associated with dental caries, but its role on caries development needs to be better clarified. Label="OBJECTIVE">To evaluate at the hard tissue level the effect of C. albicans on the cariogenic potential of S. mutans biofilms focusing on the mineral profile of induced carious lesions. This study also aimed to evaluate the effect of C. albicans on the acidogenic potential of S. mutans biofilms. METHODOLOGY Dual-species (CA+SM) and single-species biofilms (CA or SM) were grown on the surface of enamel slabs in the presence of glucose/sucrose supplemented culture medium for 24, 48 and 72 hours. Demineralization was evaluated through percentage of surface microhardness change (%SMC) and transversal microradiography analysis (ILM and LD) and pH of the spent medium was recorded daily. Data were analyzed by two-way ANOVA followed by Bonferroni correction. RESULTS%SMC was statistically different among the biofilms at each time point being the highest for SM biofilms and the lowest for CA biofilms which also differed from CA+SM biofilms [SM (24 h: 47.0±7.3; 48 h: 66.3±8.3; 72 h: 75.4±3.9); CA (24 h: 7.3±3.3; 48 h: 7.1±6.4; 72 h: 6.6±3.6); CA+SM (24 h: 35.9±7.39.1; 48 h: 47.2±9.5; 72 h: 47.6±9.5)]. pH of spent medium was statistically lower for SM biofilms compared to the other biofilms at each time point and remained constant over time while pH values increased from 24 to 72 h for both CA and CA+SM biofilms [SM (24 h: 4.4±0.1; 48 h: 4.4±0.1; 72 h: 4.5±0.1); CA (24 h: 6.9±0.3; 48 h: 7.2±0.2; 72 h: 7.5±0.2); CA+MS (24 h: 4.7±0.2; 48 h: 5.1±0.1; 72 h: 6.1±0.6)]. IML and LD for SM biofilms increased over time while no difference was observed from 24 to 72 h for the other biofilms. CONCLUSIONS The present data suggest that C. albicans has low enamel demineralization potential and the presence of C. albicans can reduce both the cariogenic and acidogenic potentials of S. mutans biofilms.

Oral Health of Hospitalized Brazilian Children: A Cross-Sectional Study

Objective: To evaluate the oral health conditions of hospitalized children, as well as describe the knowledge and practices of oral health care adopted by their parents/guardians. Material and Methods: The sample was composed of 46 children who had been hospitalized for at least five days, who had erupted teeth in the oral cavity and were accompanied by their parents/guardians. Information was collected in relation to: the oral health status of children (DMFT/DEF), the socioeconomic profile and access to information on health and oral hygiene of the parents/guardians and data regarding the hospitalization of the children. The data were analyzed using the Fisher, Pearson's and Mann Whitney's Chi-squared tests, with a confidence level of 95%. Results: 47.8% of the hospitalized children had experienced caries, and the most relevant component for the determination of the experience of caries was the presence of decayed teeth (0.50 to 1.94). A total of 97.8% of parents/guardians said they had not received information on oral health and hygiene, 100.0% had not received guidance on the sugar contained in medicines or the salivary decrease caused by the medications. 34.8% of the children did not perform oral hygiene during hospitalization. According to medical records, 58.7% took liquid medication orally. Conclusion: The hospitalized children had precarious oral health conditions, with the occurrence of carious lesions of the teeth. The presence of risk factors for dental caries in hospitalized children was observed (poor oral hygiene, low schooling and income of parents/guardians, limited knowledge of parents/guardians regarding health care and oral hygiene, consumption of medicines with cariogenic potential).

Maternal Knowledge of Oral Health of Children Aged 1-4 Years.

Knowledge of oral health (KOH) among mothers has an important influence on their children's oral habits and routines. Lack of maternal KOH had been related to the development of early childhood caries among preschool children. To assess KOH among mothers of 1-4 year-olds. Participating mothers completed a 3-part questionnaire on general demographic information, KOH of their children, and ranking of six food items according to their cariogenic potential. Most of the 285 participating mothers had an academic education. Only 47% of the mothers correctly answered seven questions on KOH. The dentist was the main source for KOH. Most of the mothers (94.39%) were aware of the need to brush their children's teeth twice daily. Most of them (72.29%) did not know the correct fluoride concentration in their child's toothpaste. They ranked salty snacks as the least cariogenic food item. Most of the mothers were not aware that snacks and sweetened drinks should be consumed during meals, and two-thirds reported tasting food from their child's spoon. Overall, mothers of toddlers lacked basic knowledge of oral health issues and practices to follow for the prevention of their children's caries.

Cariogenic Potential of Infant Formulas–An In Vitro Study

Objectives: To compare the in vitro cariogenic potential of two infant formulas (IF, for ages 6-12 months) processed with sterile distilled water with or without 1 ppm fluoride. Study design: Nine specimens in each water type were inoculated with Streptococcus mutans (SM) suspension. The specimens were then divided into one group of samples cultured immediately on Mitis salivarius (MS) agar plates (T0) and another group of specimens cultured on MS agar plates after incubation at 37°C for 4 hours in anaerobic conditions (T4). Six-fold dilutions of each sample were incubated for 48 hours, and colony-forming units (CFUs) of SM were numerated. The pH changes associated with bacterial fermentation of each of the suspensions were measured at T0 and at T4 following incubation. Results: The pH was lower at T4 than at T0 in both IF. The SM colonies increased significantly at T4 compared to T0 in both IF (P < 0.001). There was no significant difference between the CFUs of the mediums at T0 and T4 or relation between SM colonies of IF based on fluoridated and non-fluoridated distilled water. Conclusion: The cariogenic potential was not significantly different between two IF prepared with fluoridated or non-fluoridated distilled water.

Candida albicans Increases Dentine Demineralization Provoked by Streptococcus mutans Biofilm

Streptococcus mutans are considered the most cariogenic bacteria, but it has been suggested that Candida albicans could increase their cariogenicity. However, the effect of this dual-species microorganisms’ combination on dentine caries has not been experimentally evaluated. Biofilms of C. albicans, S. mutans and C. albicans + S. mutans (n = 12/biofilm) were grown in ultra-filtered tryptone yeast extract broth culture medium for 96 h on root dentine slabs of known surface hardness and exposed 8 times per day for 3 min to 10% sucrose. The medium was changed 2 times per day (after the 8 cariogenic challenges and after the overnight period of famine), and aliquots were analyzed to determinate the pH (indicator of biofilm acidogenicity). After 96 h, the biofilms were collected to determine the wet weight, colony-forming units, and the amounts of extracellular polysaccharides (soluble and insoluble). Dentine demineralization was assessed by surface hardness loss (% SHL). The architecture of the biofilms was analyzed by confocal laser scanning microscopy (CLSM) and transmission electron microscopy (TEM). Data were analyzed by ANOVA followed by Tukey’s test (α = 0.05). The dual-species C. albicans + S. mutans biofilm provoked higher % SHL on dentine (p < 0.05) than the S. mutans and C. albicans biofilm. This was supported by the results of biofilm acidogenicity and the amounts of soluble (6.4 ± 2.14 vs. 4.0 ± 0.94 and 1.9 ± 0.97, respectively) and insoluble extracellular polysaccharides (24.9 ± 9.22 vs. 18.9 ± 5.92 and 0.7 ± 0.48, respectively) (p < 0.05). The C. albicans biofilm alone presented low cariogenicity. The images by CLSM and TEM, respectively, suggest that the C. albicans + S. mutans biofilm is more voluminous than the S. mutans biofilm, and S. mutans cells interact with C. albicans throughout polysaccharides from the biofilm matrix. These findings show that C. albicans enhances the cariogenic potential of the S. mutans biofilm, increasing dentine demineralization.

Erosive and cariogenic potential of various pediatric liquid medicaments on primary tooth enamel: A SEM study.

Oral pediatric liquid medications (PLMs) are commonly used in children who suffer from chronic diseases. The physicochemical parameters of PLMs can have a deleterious effect on tooth structure. The purpose of the present study was to investigate the erosive and cariogenic effect of widespread PLMs on the surface roughness and structure of primary tooth enamel. The erosive potential of 8 common PLMs used in Egypt was assessed by measuring their inherent pH, using a digital pH electrode meter. The total sugar content was measured according to the Fehling method. The erosive effect of each liquid medicine on the enamel surface of primary teeth was assessed using scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) microanalysis for calcium (Ca) and phosphorus (P) content. Most PLMs revealed an acidic nature, with pH values ranging between 3.47 and 6.92. About 93.8% of analgesics had pH values ≤5.5, critical for enamel demineralization, whereas most antitussives and 1 antibiotic (Augmentin®) had pH values ≥6.2. Sucrose was present in all the samples studied. The SEM analysis revealed observable differences in the tooth enamel in the experimental groups, with different degrees of surface roughness and erosion. The current results suggest that the pH, sugar content and Ca dissolution ability of PLMs can significantly influence erosion in primary tooth enamel.

Cariogenic potential of sweet flavors in electronic-cigarette liquids.

BackgroundMost electronic-cigarette liquids contain propylene glycol, glycerin, nicotine and a wide variety of flavors of which many are sweet. Sweet flavors are classified as saccharides, esters, acids or aldehydes. This study investigates changes in cariogenic potential when tooth surfaces are exposed to e-cigarette aerosols generated from well-characterized reference e-liquids with sweet flavors.MethodsReference e-liquids were prepared by combining 20/80 propylene glycol/glycerin (by volume fraction), 10 mg/mL nicotine, and flavors. Aerosols were generated by a Universal Electronic-Cigarette Testing Device (49.2 W, 0.2 Ω). Streptococcus mutans (UA159) were exposed to aerosols on tooth enamel and the biological and physiochemical parameters were measured.ResultsE-cigarette aerosols produced four-fold increase in microbial adhesion to enamel. Exposure to flavored aerosols led to two-fold increase in biofilm formation and up to a 27% decrease in enamel hardness compared to unflavored controls. Esters (ethyl butyrate, hexyl acetate, and triacetin) in e-liquids were associated with consistent bacteria-initiated enamel demineralization, whereas sugar alcohol (ethyl maltol) inhibited S. mutans growth and adhesion. The viscosity of the e-liquid allowed S. mutans to adhere to pits and fissures. Aerosols contained five metals (mean ± standard deviation): calcium (0.409 ± 0.002) mg/L, copper (0.011 ± 0.001) mg/L, iron (0.0051 ± 0.0003) mg/L, magnesium (0.017 ± 0.002) mg/L, and silicon (0.166 ± 0.005) mg/L.ConclusionsThis study systematically evaluated e-cigarette aerosols and found that the aerosols have similar physio-chemical properties as high-sucrose, gelatinous candies and acidic drinks. Our data suggest that the combination of the viscosity of e-liquids and some classes of chemicals in sweet flavors may increase the risk of cariogenic potential. Clinical investigation is warranted to confirm the data shown here.

Maltodextrin and dental caries: a literature review

ABSTRACT Carbohydrates are largely present in our diet. Sucrose the most commonly consumed carbohydrat and presents a high cariogenic potential. Starch has low cariogenic potential but this effect may be increased if it is consumed in combination with a sucrose-rich diet due to a prolonged retention on tooth surfaces. Maltodextrin is derived from the acid hydrolysis and/or enzymatic hydrolysis of corn starch and it is increasingly present in a variety of industrialized foods such as infant formulas, sports drinks and energy supplements. Yet, its role in the development of dental caries is not clear. The objective of this study was to conduct a literature review of the association between maltodextrin and dental caries. Based on the studies included in this review it can be concluded that maltodextrin has an acidogenic potential lower than sucrose, and that there is a lack of studies about the association between maltodextrin and sucrose and it may not be possible to assess the relationship to dental caries.

Analysis of oral health conditions and risk factors for dental caries in patients with sickle cell disease

ABSTRACT Objective: To analyze the oral health conditions and risk factors for caries in patients with sickle cell disease. Methods: An observational, cross-sectional study was conducted in the clinic of the Association of Persons with Hemoglobinopathies of Alagoas, in the city of Maceió-AL, Brazil. The sample composed of 43 patients were included by census sampling. The ICDAS/DMFT/dmf-t caries indices were used, and simplified oral hygiene, salivary flow and buffer capacity tests were performed. Patients were interviewed to check their level of knowledge about oral hygiene and diet. Spearman correlation and ANOVA statistical tests were applied (p&lt;0.05). Results: The mean DMFT was 15.49±4.43; oral hygiene regular (IHOS=2.22±0.18); mean salivary flow 0.92±0.26, and mean buffer capacity 4.60±0.32. Correlation was found between salivary flow and buffer capacity (p = 0.009). Patients with the highest caries prevalence, in the age-ranges 6 to 12, and 20 to 26 years, had the lowest buffer capacity values (p = 0.04). Interviews showed that 58% did not use dental floss, 88% consumed cariogenic snacks, 100% reported never having received guidance from dentists about the cariogenic potential of foods and 60% reported the use of anticholinergic medications to reduce drooling (Tramal® and morphine) during pain crises. Conclusion: These patients presented extremely high caries prevalence, with predominance of carious teeth. The salivary parameters analyzed and level of knowledge about oral hygiene and cariogenic diet presented, showed that patients with sickle cell disease belonged to a group with risk for development of dental caries.

Association between Oral Candida and Bacteriome in Children with Severe ECC

Candida albicans is an opportunistic fungal organism frequently detected in the oral cavity of children with severe early childhood caries (S-ECC). Previous studies suggested the cariogenic potential of C. albicans, in vitro and in vivo, and further demonstrated its synergistic interactions with Streptococcus mutans. In combination, the 2 organisms are associated with higher caries severity in a rodent model. However, it remains unknown whether C. albicans influences the composition and diversity of the entire oral bacterial community to promote S-ECC onset. With 16s rRNA amplicon sequencing, this study analyzed the microbiota of saliva and supragingival plaque from 39 children (21 S-ECC and 18 caries-free [CF]) and 33 mothers (17 S-ECC and 16 CF). The results revealed that the presence of oral C. albicans is associated with a highly acidogenic and acid-tolerant bacterial community in S-ECC, with an increased abundance of plaque Streptococcus (particularly S. mutans) and certain Lactobacillus/Scardovia species and salivary/plaque Veillonella and Prevotella, as well as decreased levels of salivary/plaque Actinomyces. Concurrent with this microbial community assembly, the activity of glucosyltransferases (cariogenic virulence factors secreted by S. mutans) in plaque was significantly elevated when C. albicans was present. Moreover, the oral microbial community composition and diversity differed significantly by disease group (CF vs. S-ECC) and sample source (saliva vs. plaque). Children and mothers within the CF and S-ECC groups shared microbiota composition and diversity, suggesting a strong maternal influence on children’s oral microbiota. Altogether, this study underscores the importance of C. albicans in association with the oral bacteriome in the context of S-ECC etiopathogenesis. Further longitudinal studies are warranted to examine how fungal-bacterial interactions modulate the onset and severity of S-ECC, potentially leading to novel anticaries treatments that address fungal contributions.

Sucrose challenges to Streptococcus mutans biofilms and the curve fitting for the biofilm changes.

The relationship between sugar level and development of dental caries has long been a main topic in dentistry. However, as a ubiquitous component of the modern diet, sucrose is mainly derived from three meals a day, rather than a long time exposure. In this study, various concentrations of sucrose were provided to Streptococcus mutans biofilms for 1 h per exposure (three times per day) to imitate a human meal pattern. And then the relationship between sucrose concentration and changes in the treated biofilms was determined. The results indicated that the components and acid production of the treated biofilms changed in a second-order polynomial curve pattern with sucrose concentration increase, which were confirmed by CLSM and SEM analyses. However, gene expression related to extracellular polysaccharides (EPS) formation, acid production and tolerance was up-regulated with sucrose concentration increase, which might have been due to compensation for the decrease in EPS formation and acid production by the biofilms at higher concentrations of sucrose. These findings suggest that sucrose in the range of 1%-5% can support the highest acid production and accumulation of S. mutans biofilms, which may further increase its cariogenic potential. However, additional studies are required to confirm the relationships in human cariogenic biofilms.

Assessment of plaque pH after oral rinsing with four customary used types of complementary infant formula

Background: Complementary infant formulas are the second most important sources of nutrition for neonates after breast milk. Considering the cariogenic potential of infant formulas, selection of these nutritive sources should be safe to reduce the risk of baby bottle syndrome in newborns. The present study aimed to estimate the plaque pH changes after rinsing with four customary used types of complementary infant formula. Methods: An in-vivo, in-vitro study was conducted on five healthy neonates aged 12-18 months to assess the plaque pH changes caused by rinsing with four different types of complementary infant formula, including Rice and Milk Cerelac, Wheat and Milk Cerelac, Banana and Milk Humana, and Peach and Milk Humana. Data analysis was performed in SPSS version 17 using paired t-test to compare the pH changes associated with each formula. In all the statistical analyses, P-value of less than 0.01 was considered significant. Results: All the formulas significantly reduced the plaque pH to less than the pre-rinse pH. However, the plaque pH decreased to less than the critical pH level (<5.7), particularly in the infants using the Rice and Milk Cerelac formula. Conclusion: According to the results, rinsing with the Rice and Milk Cerelac formula reduced the plaque pH value more than the other formulas. Therefore, it seems that complementary infant formulas could decrease the plaque pH and play a key role in the development of caries in neonates depending on the ingredients.