The Identification of Oral Cariogenic Bacteria through Colorimetric Sensor Array Based on Single-Atom Nanozymes.

Effective identification of multiple cariogenic bacteria in saliva samples is important for oral disease prevention and treatment. Here, a simple colorimetric sensor array is developed for the identification of cariogenic bacteria using single-atom nanozymes (SANs) assisted by machine learning. Interestingly, cariogenic bacteria can increase oxidase-like activity of iron (Fe)─nitrogen (N)─carbon (C) SANs by accelerating electron transfer, and inversely reduce the activity of Fe─N─C further reconstruction with urea. Through machine-learning-assisted sensor array, colorimetric responses are developed as "fingerprints" of cariogenic bacteria. Multiple cariogenic bacteria can be well distinguished by linear discriminant analysis and bacteria at different genera can also be distinguished by hierarchical cluster analysis. Furthermore, colorimetric sensor array has demonstrated excellent performance for the identification of mixed cariogenic bacteria in artificial saliva samples. In view of convenience, precise, and high-throughput discrimination, the developed colorimetric sensor array based on SANs assisted by machine learning, has great potential for the identification of oral cariogenic bacteria so as to serve for oral disease prevention and treatment.

The oral microbiota and periodontal health in orthodontic patients.

The oral microbiota develops within the first 2 years of childhood and becomes distinct from the parents by 4 years-of-age. The oral microbiota plays an important role in the overall health/symbiosis of the individual. Deviations from the state of symbiosis leads to dysbiosis and an increased risk of pathogenicity. Deviations can occur not only from daily life activities but also from orthodontic interventions. Orthodontic appliances are formed from a variety of biomaterials. Once inserted, they serve as a breeding ground for microbial attachment, not only from new surface areas and crevices but also from material physicochemical interactions different than in the symbiotic state. Individuals undergoing orthodontic treatment show, compared with untreated people, qualitative and quantitative differences in activity within the oral microbiota, induced by increased retention of supra- and subgingival microbial plaque throughout the treatment period. These changes are at the root of the main undesirable effects, such as gingivitis, white spot lesions (WSL), and more severe caries lesions. Notably, the oral microbiota profile in the first weeks of orthodontic intervention might be a valuable indicator to predict and identify higher-risk individuals with respect to periodontal health and caries risk within an otherwise healthy population. Antimicrobial coatings have been used to dissuade microbes from adhering to the biomaterial; however, they disrupt the host microbiota, and several bacterial strains have become resistant. Smart biomaterials that can reduce the antimicrobial load preventing microbial adhesion to orthodontic appliances have shown promising results, but their complexity has kept many solutions from reaching the clinic. 3D printing technology provides opportunities for complex chemical syntheses to be performed uniformly, reducing the cost of producing smart biomaterials giving hope that they may reach the clinic in the near future. The purpose of this review is to emphasize the importance of the oral microbiota during orthodontic therapy and to use innovative technologies to better maintain its healthy balance during surgical procedures.

Radiation-induced xerostomia and cariogenic dietary habits.

PURPOSE: Despite the availability of various prevention methods, dental caries continue to be diagnosed in patients receiving head and neck radiotherapy (RT). Since conventional approaches do not evaluate posttreatment alterations in dietary behaviors, we aimed to assess the influence of radiation-induced xerostomia on post-RT cariogenic dietary habits in patients. METHODS: Fifty-seven patients completed the Xerostomia Questionnaire (XQ) and answered questions regarding daily cariogenic food and beverage (CFB) intake, daily tooth brushing, fluoride application, and subjective total taste acuity (STTA). They also underwent evaluations to determine the Simplified Oral Hygiene Index (OHI-S) score, Saxon test score, number of decayed-missing-filled teeth (DMFT), and proportion of DMFT to the test teeth (DMFT rate). Clinical records were searched for information regarding RT modalities, including the median of the mean dose to the parotid glands, days after the completion of RT, submandibular gland resection, whole-neck irradiation, and the DMFT value and rate before RT. The patients were divided into low and high XQ score groups based on the median XQ score of 47.5 for the two sample tests. Univariable and multivariable regression analyses were used to identify independent factors for frequent CFB intake. RESULTS: Higher XQ scores were associated with a significantly greater frequency of CFB intake (p = 0.028*). Regression analysis also identified a higher XQ score (p = 0.017*) as an independent risk factor for frequent CFB intake. CONCLUSION: Radiation-induced xerostomia increased the frequency of CFB intake.

Analysis of ten-year teaching evaluation of oral microbiology lab curriculum.

BACKGROUND: Based on the updated teaching philosophy of oral microbiology, Wuhan University School of Stomatology initiated a reform in the teaching of oral microbiology in 2009. As part of this reform, an oral microbiology laboratory course was introduced to cultivate students' fundamental skills, professional competence, comprehensive abilities, and innovation capabilities through experimental design. This paper provides thorough examination of the teaching experiment findings from 2013 to 2022, a ten-year timeframe, building on earlier data. METHODS: The curriculum targets fourth-year undergraduate students in a five-year program and adopts a cooperative learning approach. The experimental teaching mainly involves four parts: plaque collection and processing, isolation and cultivation of dental plaque bacteria, staining and biochemical identification of dental plaque bacteria. This article presents a comprehensive analysis of the student experiment results from 2013 to 2022. Statistical analysis was conducted using the chi-square test to assess whether there were any differences in students' experimental grades between different years. A significance level of P < 0.05 was considered statistically significant. Additionally, we evaluated the impact of teaching methods and educational systems on improving students' practical skills and overall innovative abilities. RESULTS: The performance of 664 undergraduate students showed improvement in the oral microbiology laboratory course, with a noticeable decrease in the proportion of "C" grades in Experiments 2, 3, and 4 compared to Experiment 1. These results indicate that the laboratory course enhanced students' academic achievements, aiding their understanding and mastery of course content, and received positive feedback from the students. CONCLUSION: This lab curriculum, through systematic laboratory teaching and practical experience, contributes to the enhancement of students' professional skills and research abilities. It fosters students' interest in scientific research and improves the quality of dental education.

Level of support/commitment and behavior during mealtime and dental care negatively impact the dental caries prevalence in autistic individuals: cross-sectional study.

OBJECTIVE: To verify whether factors associated with Autism Spectrum Disorder (ASD) would have impact on the dental-caries prevalence. MATERIALS AND METHODS: All ASD-individuals receiving care in a specialized center with minimum of 4y old were recruited. Demographic, socioeconomic and behavioral characteristics, level of support/commitment (Childhood Autism Rating Scale), mealtime behavior (Brief Autism Mealtime Behavior Inventory) and medication use were answered by ASD-individual's parents. Behavior during dental care was evaluated from Frankl scale. Dental-caries prevalence was the primary outcome. Three examiners calibrated/trained collected the data. Chi-square test was used to compare the variables impact on the dental-caries prevalence. RESULTS: 61 ASD-individuals were potentially eligible, and the all parents/guardians consent to participate. Dental-caries prevalence was 42.9%, which was statistically associated with lower toothbrushing frequency, higher level of support/commitment, and worse behavior at meals and during in dental care. Dental-caries prevalence was approximately higher twice in ASD-individuals: (i) uncooperative with dental care when compared those cooperative (62% versus 32%, respectively); (ii) with severe level of support when compared to those with mild/moderate level (58% versus 28%, respectively); and (iii) with worse mealtime behavior when compared to those with better behavior (59% versus 28%, respectively). A medium statistical correlation was observed between support level and mealtime behavior (rS=0.39). The BAMBI component statistically associated with dental-caries prevalence was the food refusal (capture problem when a child rejects a presented food, crying, spitting out food). CONCLUSION: higher required level of support, worse mealtime behavior and uncooperative profile in dental care negatively affect the dental-caries prevalence. CLINICAL RELEVANCE: our findings provide evidence of the need of specialized, preventive and individualized dental care among ASD-individuals.

Relationship between parental adverse childhood experiences and the prevalence of early childhood caries.

OBJECTIVES: The aim of this study was to examine the behavioural health conditions associated with parents' retrospective adverse childhood experiences (ACEs) scores and their children's early childhood caries (ECC) in parent-child dyads. MATERIALS AND METHODS: Parents with children younger than 72 months were included in the study. A relational screening model was used. Interaction among ACEs, ECC, nutritional habits and oral hygiene habits were evaluated. Chi-square tests and t-tests were used in the study. Multiple variables were evaluated using the artificial neural network (ANN) model. RESULTS: The mean age of the 535 children included in the study was 46.5 months, and 52% were female. Using the ANN model, there was a statistically significant relationship between the educational status of the mothers in both the ECC and severe ECC (S-ECC) groups and the socioeconomic status of the family (p < 0.05). If the number of snacks consumed daily was three or more, the risk of ECC was statistically significantly higher (chi-square test p = 0.034). The parents' ACEs scores had an impact on both ECC and S-ECC formation (p = 0.001, t-test). The higher the ACEs score, the higher the risk of S-ECC. The mean ACEs scores of the parents were also significantly higher in both the ECC and S-ECC groups compared to those of the parents of children without dental caries (p = 0.001, t-test). It was calculated that ACEs scores were effective at a rate of 18.2% on ECC (p = 0.045, ANN). CONCLUSIONS: The ACEs scores of parents have an impact on the oral health of young children and ECC/S-ECC formation. CLINICAL RELEVANCE: The long-term effects of parental ACEs are reflected in their children's oral health. Therefore, reducing the psychosocial determinants ACEs and providing parental support may help in overcoming barriers to the well-being of young children and may facilitate better oral health.

Association of temperament with oral health behaviour and caries status in Thai preschool children.

BACKGROUND: Temperament associated with oral health behaviour and early childhood caries (ECC) in preschoolers remains inconclusive. AIM: This cross-sectional study investigated the association of temperament with oral health behaviour and ECC status. DESIGN: A total of 421 Thai preschoolers were recruited from elementary schools in Chonburi Province, Thailand. Their caregivers assessed three temperament dimensions (surgency, negative affectivity and effortful control) using the Thai version of the Children's Behaviour Questionnaire Very Short Form and reported oral health behaviours (brushing cooperation and cariogenic snack frequency). Three calibrated dentists assessed ECC status using the modified WHO dmft/dmfs (decayed, missing and filled teeth/surface) index that included noncavitated and cavitated carious lesions. RESULTS: Multiple regression analysis, after adjusting for child's and caregiver's characteristics, revealed that children with high negative affectivity or low effortful control were more likely to have uncooperative brushing behaviour. The temperament scores of children who consumed cariogenic snacks daily and those who did not were comparable. Children with low surgency, high negative affectivity or low effortful control were more likely to have high dmfs scores. CONCLUSION: Negative affectivity and effortful control were associated with brushing behaviour. Temperament was not associated with the frequency of cariogenic snack consumption. All temperamental dimensions, however, were associated with ECC.

The impact of a-tomatine on shear bonding strength in different dentin types and on cariogenic microorganisms: an in vitro and in silico study.

INTRODUCTION: The objective of this study is to investigate the shear bonding strength of a glycoalkaloid, also a novel matrix metalloproteinase enzyme known as α-tomatine, on two different surfaces of dentin (sound & caries-affected) and its efficacy against cariogenic microorganisms using in vitro and in silico methods. METHODS: The effect of a-tomatine at different concentrations (0.75 / 1 / 1.5 µM) on shear bonding strength in caries-affected and sound dentin was also investigated (n = 10; each per subgroup). The analysis of shear bonding and failure tests was conducted after a 24-hour storage period. Fracture surfaces were examined under a scanning electron microscope. A stock solution 3 mM of a-tomatine was prepared for antimicrobial evaluation. Antimicrobial activities of the agents against Streptococcus mutans ATCC 25175, Lactobacillus casei ATCC 4646, and Candida albicans ATCC 10231 standard strains were investigated by microdilution method. In addition, through the method of molecular docking and dynamic analysis, the affinity of a-tomatine for certain enzymes of these microorganisms was examined. RESULTS: The pretreatment agent and dentin type significantly influenced shear bonding strength values (p < 0.05). As the molarity of a-tomatine increased, the bonding value decreased in sound dentin, while the opposite was true in caries-affected dentin. According to molecular docking and dynamic analysis, the highest affinity was observed in L. casei's signaling protein. Microdilution assays revealed a-tomatine to exhibit fungicidal activity against C. albicans and bacteriostatic effects against S. mutans. No antimicrobial effect was observed on L. casei. CONCLUSION: a-tomatine demonstrates a positive impact by serving as both a pretreatment agent for bonding strength and an inhibitor against certain cariogenic microorganisms.

Caries indicators in relation to healthcare access and hygienic-dietary habits in Spanish preschoolers.

INTRODUCTION: Dental caries continues to be a public healthcare problem due to its high prevalence and morbidity. It was proposed to evaluate caries indicators in relation to healthcare access and hygienic-dietary habits in Spanish preschoolers. MATERIALS AND METHODS: A cross-sectional study was carried out on a random sample consisting of 343 patients ranging from 3 to 5 years of age in the primary care setting, the main measurements were: dental care access, hygienic-dietary habits, and caries registration according to WHO criteria. RESULTS: The prevalence of caries was 35.3% and mean ± standard deviation (SD) dft was 1.51 ± 2.93. Preschoolers who had ever visited the dentist had a higher dft occurrence than those who had never attended the dentist. The lower prevalence of caries was significantly associated with the frequency of two daily brushings versus non-daily brushing (p = 0.007; 25.3% vs. 47.1%) and was 10.7% lower in patients who had the habit of night brushing (p = 0.041). The consumption of sugary liquids between meals implied a higher dft index. CONCLUSIONS: The high prevalence of early childhood caries and the dental care access associated with poor oral health suggest the need to implement a multidisciplinary oral healthcare program that involves both healthcare and dental healthcare professionals in Primary Health Care Units without forgetting the participation of the community and local administrations.

Standardization of the Right Heart Catheterization and the Emerging Role of Advanced Hemodynamics in Heart Failure.

The accurate assessment of hemodynamics is paramount to providing timely and efficacious care for patients presenting in cardiogenic shock. Recently, the regular use of the pulmonary artery catheter in cardiogenic shock has had a resurgence with emerging data indicating improved survival in the modern era. Optimal multidisciplinary management of advanced heart failure and cardiogenic shock relies on our ability to effectively communicate and understand the complete hemodynamic assessment. Standardization of data acquisition and a renewed focus on the physiological processes, and thresholds driving disease progression, including the coupling ratio and myocardial reserve, are needed to fully understand and interpret the hemodynamic assessment. This State-of-the-Art review discusses best practices in the cardiac catheterization laboratory as well as emerging data on the prognostic role of emerging advanced hemodynamic parameters.

Immediate and Sustained Root Caries Prevention of Fluoride Varnish Combined with Toothpastes.

The aim of this study was to determine the immediate and sustained effect of a fluoride varnish and its combinations with toothpastes in preventing root caries development using a salivary microcosm in vitro model. Human root dentin specimens (n = 150) were randomly divided into 5 experimental protocols (n = 30): (1) Fluoride Varnish (V); (2) V followed by Paste One (V + PO); (3) V followed by Paste Plus (V + PP); (4) V followed by PO and PP (V + PO + PP); and (5) No treatment (control). One varnish layer was applied on the specimens (except for the control group) and kept for 18 h. Then, the varnish was removed and toothpaste treatments were initiated according to experimental groups. For the short-term incubation model (n = 15), the specimens were also immediately subjected to 7-day cariogenic challenge. For that, human saliva was used as bacterial inoculum and McBain artificial saliva containing 2% sucrose as growth medium. The other half of the specimens (n = 15) were used to study the varnish's sustained effect by long-term incubation (8 weeks) before cariogenic challenge. The protocols' anti-caries properties were evaluated by dentin porosity (rhodamine intensity; RI) and mineral density, while their anti-biofilm effects were evaluated using biofilm's biomass and viability assays. For short- and long-term incubation models, all experimental regimens resulted in statistically significant decreases (p < 0.05) in the RI (up to 180 µm and 120 µm, respectively) as well as higher mineral density compared to No treatment (p < 0.001). V + PO + PP and/or V + PO resulted in statistically lower RI compared to V for some depths (p < 0.05) in both models. There were changes in RI and mineral density within groups over time. All experimental treatments exhibited anti-biofilm effects. All prevention protocols exhibited immediate and sustained anti-caries effect against root caries development. The combination of a fluoride varnish with PO resulted in superior additional anti-caries effects.

Mother's Experience of Conflict Within Their Family Social Network when Advocating for Children's oral Health.

OBJECTIVES: Examine whether mothers perceived that child oral health was a source of conflict in family relationships. METHODS: This cross-sectional qualitative study consisted of 126 semi-structured interviews with mothers of 3-5 year-old children from West Virginia and Pittsburgh, Pennsylvania. Interviews consisted of open-ended questions on the mother's social relationships that affected child dental visits, oral hygiene, and diet. The data were analyzed using template analysis. RESULTS: Over 85% (n = 111/126) of mothers reported interpersonal conflict in their familial relationships related to child oral health. Most (78%) mothers reported conflict with their partners and 58% of mothers reported conflict with the child's grandparents. Conflicts primarily centered around keeping a consistent oral hygiene routine for the child and the promotion of a low-cariogenic diet. CONCLUSIONS FOR PRACTICE: Mothers perceived child oral health promotion as a source of conflict in the family. This study suggests that identifying effective strategies to reduce conflict with caretakers are indicated. Oral health professionals can take an active role not only in communicating with the mother, but also with other caretaking adults in the family to promote oral health practices that benefit all children.

Cariogenic diet consumption during lockdown.

BACKGROUND: During stressful situations such as pandemic-associated lockdowns, individuals' diets may change towards (cariogenic) 'comfort food'. This study assessed the dietary patterns during the lockdown in the Colombian population. METHODS: A cross-sectional online survey was designed. A convenience sample of 489 adults was drawn, with 50% of them being in COVID-19 lockdown and the other being not or only partially in lockdown. The questionnaire collected data about the type and frequency of food consumed, with a special focus on cariogenic (i.e., rich in free sugars and starches) food. Descriptive analyses were performed, and a generalised linear model was estimated to predict the frequency of cariogenic diet consumption in this period of time. RESULTS: Sweet whole wheat bread (38.2%, p = 0.005), flavoured milk (26.4%, p = 0.002), sugar-sweetened bubble gums (39.8%, p = 0.001), toffees (35.4%, p = 0.004), soft candies (e.g., gums) (35.4%, p = 0.018), chocolates (55.3%, p = 0.017), filled doughnuts (28.5%, p = 0.013) or grapes (51.2%, p = 0.002) were significantly consumed more during the lockdown. Multivariable generalised linear modelling showed being single, having children and being in lockdown were significantly associated with higher frequency of cariogenic food consumption. CONCLUSIONS: Lockdown was found to be associated with detrimentally altered food consumption patterns and, specifically, a more cariogenic diet. Healthcare professionals should consider this when reopening services, and political decision-makers may want to reflect on the unwarranted side effect of lockdown.

Factors associated with a cariogenic diet among adolescents: a structural equation modeling approach.

OBJECTIVE: To investigate the factors directly and indirectly associated with a cariogenic diet among southern Brazilian adolescents. MATERIALS AND METHODS: This cross-sectional study included 15-19-year-old students attending high schools in Santa Maria, southern Brazil. The participants completed a questionnaire on sociodemographic and behavioral variables. The Oral Health Impact Profile-14 was applied to collect data on oral health-related quality of life (OHRQoL). Clinical examination was used to assess the dental caries status (decayed, missing, and filled teeth index). A cariogenic diet was considered a latent variable measured by the self-perception of a healthy diet and the frequency of consumption of sugary foods and drinks. Structural equation modeling was used to analyze the direct and indirect pathways to a cariogenic diet. RESULTS: A total of 1197 adolescents were included. Low toothbrushing frequency (standardized coefficient (SC), 0.10; p < 0.05), cigarette smoking (SC, 0.15; p < 0.01), and alcoholic beverages (SC, 0.14; p < 0.01) were directly linked to a cariogenic diet, which, in turn, was directly linked to untreated dental caries (SC, 0.18; p < 0.01) and poor OHRQoL (SC, 0.16; p < 0.01). In addition, household income (via toothbrushing frequency) and age (via alcoholic beverages) were indirectly linked to a cariogenic diet. CONCLUSION: A cariogenic diet was consistently associated with a range of unhealthy behaviors during adolescence as well as poor household income. CLINICAL RELEVANCE: Health promotion strategies to restrict sugar consumption and encourage healthier lifestyles should be aware of the synergism observed among unhealthy behaviors during adolescence.

Modified Lactoperoxidase System as a Promising Anticaries Agent: In Vitro Studies on Streptococcus mutans Biofilms.

The lactoperoxidase (LPO) system shows promise in the prevention of dental caries, a common chronic disease. This system has antimicrobial properties and is part of the non-specific antimicrobial immune system. Understanding the efficacy of the LPO system in the fight against biofilms could provide information on alternative strategies for the prevention and treatment of caries. In this study, the enzymatic system was modified using four different (pseudo)halide substrates (thiocyanate, thiocyanate-iodide mixture, selenocyanate, and iodide). The study evaluated the metabolic effects of applying such modifications to Streptococcus mutans; in particular: (1) biofilm formation, (2) synthesis of insoluble polysaccharides, (3) lactate synthesis, (4) glucose and sucrose consumption, (5) intracellular NAD+ and NADH concentrations, and (6) transmembrane glucose transport efficiency (PTS activity). The results showed that the LPO-iodide system had the strongest inhibitory effect on biofilm growth and lactate synthesis (complete inhibition). This was associated with an increase in the NAD+/NADH ratio and an inhibition of glucose PTS activity. The LPO-selenocyanate system showed a moderate inhibitory effect on biofilm biomass growth and lactate synthesis. The other systems showed relatively small inhibition of lactate synthesis and glucose PTS but no effect on the growth of biofilm biomass. This study provides a basis for further research on the use of alternative substrates with the LPO system, particularly the LPO-iodide system, in the prevention and control of biofilm-related diseases.

Effect of Chitosan on the Number of Streptococcus mutans in Saliva: A Meta-Analysis and Systematic Review.

We conducted a meta-analysis and systematic review to investigate the efficacy of chitosan-containing chewing gums, and to test their inhibitory effects on Streptococcus mutans. The systematic search was performed in three databases (Cochrane Library, EMBASE, and PubMed) and included English-language randomized-controlled trials to compare the efficacy of chitosan in reducing the number of S. mutans. To assess the certainty of evidence, the GRADE tool was used. Mean differences were calculated with a 95% confidence interval for one outcome: bacterial counts in CFU/mL. The protocol of the study was registered on PROSPERO, registration number CRD42022365006. Articles were downloaded (n = 6758) from EMBASE (n = 2255), PubMed (n = 1516), and Cochrane (n = 2987). After the selection process, a total of four articles were included in the qualitative synthesis and three in the quantitative synthesis. Our results show that chitosan reduced the number of bacteria. The difference in mean quantity was -4.68 × 105. The interval of the random-effects model was [-2.15 × 106; 1.21 × 106] and the prediction interval was [1.03 × 107; 9.40 × 106]. The I2 value was 98% (p = 0.35), which indicates a high degree of heterogeneity. Chitosan has some antibacterial effects when used as a component of chewing gum, but further studies are needed. It can be a promising antimicrobial agent for prevention.

Effects of Tea Polyphenols and Theaflavins on Three Oral Cariogenic Bacteria.

In order to investigate the antibacterial mechanism of tea polyphenols and theaflavins against oral cariogenic bacteria, the pH value of the culture medium, the number of bacteria adhering to the smooth glass tube wall, and the electrical conductivity value within 10 h were measured, respectively. The effects of four concentrations of tea polyphenols and theaflavins below the MIC value were studied on acid production, adhesion, and electrical conductivity of oral cariogenic bacteria. The live/dead staining method was used to observe the effects of four concentrations of tea polyphenols and theaflavins below the MIC value on the biofilm formation of oral cariogenic bacteria under a laser scanning confocal microscope. With the increase in concentrations of tea polyphenols and theaflavins, the acid production and adhesion of the cariogenic bacteria gradually decreased, and the conductivity gradually increased. However, the conductivity increase was not significant (p < 0.05). Compared with the control group, the 1/2MIC and 1/4MIC tea polyphenols and theaflavins treatments significantly reduced the biomass of the cariogenic biofilm (p < 0.05). The confocal laser scanning microscope showed that the integrated optical density of green fluorescence of the cariogenic biofilm gradually decreased with the increase in agent concentration after the action of tea polyphenols and theaflavins.

Bonding durability and remineralizing efficiency of orthodontic adhesive containing titanium tetrafluoride: an invitro study.

BACKGROUND: Titanium tetrafluoride has been shown to protect tooth enamel from demineralization. This study investigated the effect of incorporating different concentrations of TiF4 (1, 2 and 3 Wt.%) into an orthodontic primer on the shear bond strength of orthodontic brackets and the enamel microhardness after cariogenic challenges. METHODS: Three different TiF4 concentrations (1, 2 and 3 Wt.%) were prepared and added to the etch and rinse orthodontic primer. Ninety freshly extracted premolars were randomly divided into five groups according to the experimental primers and ageing conditions: TF0, TF0C, TF1C, TF2C, and TF3C. The TF0C group had no TiF4 in the primer, while TF1C, TF2C, and TF3C had 1, 2 and 3 Wt.% TiF4 in the primer, respectively. In the TF0 group, specimens were immersed in deionized water for 24 h as a control group, while all other groups were immersed in a demineralizing solution for 28 days. Each of the five groups was divided into two subgroups: The first group was subjected to shear bond strength and adhesive remnant index testing (N = 50 teeth, 10/group), while the second group was subjected to enamel surface microhardness testing (N = 25 teeth, 50 tooth halves, 10 tooth halves/group). Fifteen teeth (N = 15 teeth, n = 3/group) representing the five groups were subjected to SEM and microelemental analysis (EDX). SBS, ARI, microhardness, and Ca/P ratio were measured, and the data were analyzed using ANOVA and Tukey's tests. RESULTS: The TF2C group had the highest SBS value (9.93 ± 1.23), while the TF0C (5.24 ± 0.65) and TF3C (5.13 ± 0.55) had the lowest SBS values. The enamel microhardness in the TF0C group was significantly reduced (p < .001). Enamel microhardness values were significantly (p < .001) higher in groups TF1C, TF2C, and TF3C than in TF0C. The highest Ca/P ratio was significantly recorded for the TF2C group (2.65 ± 0.02). CONCLUSIONS: Incorporation of 1 and 2 Wt.% TiF4 into the orthodontic primers showed adequate bond strength and better remineralization effect. However, 1 Wt.% TiF4 showed lower ARI values than 2 Wt.% TiF4.

Relation between caries experience and the consumption of sweetened drinks and processed food in children: A population-based study.

OBJECTIVES: Diet can play a role in caries disease and the consumption of ultra-processed foods has increased over the years. The purpose was to propose predictive models on the relation between caries experience, diet, sex, and oral health aspects. METHODS: This cross-sectional study included 5213 schoolchildren aged 2-11 years and a questionnaire based on WHO Oral Health Survey was applied to assess the intake of sugary foods, oral hygiene practices, access to health services and parents' perception; dmft/DMFT index, biofilm accumulation and orthodontic treatment need were assessed by 6 calibrated dentists. RESULTS: The logistic model showed that female sex and presence of biofilm increased the chance of having early childhood caries; besides, this chance increased by 17% for each additional day of sweetened drink intake. In children aged 6-11 years, a negative binomial regression model showed that the absence of biofilm and frequency of toothbrushing were related to lower caries index, while male sex and the consumption of salty snacks and cake/cookies were related to higher dmft+DMFT index. Disagreement or weak agreement between caregivers' perception of the presence of dental caries and children's need for dental treatment was found. CONCLUSION: Early childhood caries was dependent on the consumption of sweetened drinks and the presence of biofilm, while in older children the caries experience was predicted by the consumption of snacks, cakes and biscuits, biofilm accumulation and toothbrushing frequency, emphasizing the need of health education to encourage healthy eating habits and oral care with an approach to parents/caregivers to prevent dental caries development.

Lactobacillus cell envelope-coated nanoparticles for antibiotic delivery against cariogenic biofilm and dental caries.

BACKGROUND: Due to their prevalence, dental caries ranks first among all diseases endangering human health. Therefore, the prevention of caries is of great significance, as caries have become a serious public health problem worldwide. Currently, using nanoscale drug delivery systems to prevent caries has received increased attention. However, the preventive efficacy of these systems is substantially limited due to the unique physiological structure of cariogenic biofilms. Thus, novel strategies aimed at combating cariogenic biofilms to improve preventive efficiency against caries are meaningful and very necessary. Herein, inspired by cell membrane coating technology and Lactobacillus strains, we coated triclosan (TCS)-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles (TCS@PLGA-NPs) with an envelope of Lactobacillus (LA/TCS@PLGA-NPs) and investigated their potential as a nanoparticle delivery system against cariogenic biofilms and dental caries. RESULTS: LA/TCS@PLGA-NPs were successfully prepared with favorable properties, including a coated envelope, controllable size, negative charge, sustained drug-release kinetics and so on. The LA/TCS@PLGA-NPs inherited native properties from the source cell surface, thus the LA/TCS@PLGA-NPs adhered to S. mutans, integrated into the S. mutans biofilm, and interfered with the biofilm formation of S. mutans. The nanoparticles significantly inhibited the activity, biomass and virulence gene expression of S. mutans biofilms in vitro. Additionally, LA/TCS@PLGA-NPs exhibited a long-lasting inhibitory effect on the progression of caries in vivo. The safety performance of the nanoparticles is also favorable. CONCLUSIONS: Our findings reveal that the antibiofilm effect of LA/TCS@PLGA-NPs relies not only on the inheritance of native properties from the Lactobacillus cell surface but also on the inhibitory effect on the activity, biomass and virulence of S. mutans biofilms. Thus, these nanoparticles could be considered feasible candidates for a new class of effective drug delivery systems for the prevention of caries. Furthermore, this work provides new insights into cell membrane coating technology and presents a novel strategy to combat bacterial biofilms and associated infections.