Salivary proteins and microbiota as biomarkers for early childhood caries risk assessment

Mass spectrometry-based proteomic approaches for salivary protein biomarkers discovery and dental caries diagnosis: A critical review

Dental caries is a multifactorial chronic disease resulting from the intricate interplay among acid-generating bacteria, fermentable carbohydrates, and several host factors such as saliva. Saliva comprises several proteins which could be utilized as biomarkers for caries prevention, diagnosis, and prognosis. Mass spectrometry-based salivary proteomics approaches, owing to their sensitivity, provide the opportunity to investigate and unveil crucial cariogenic pathogen activity and host indicators and may demonstrate clinically relevant biomarkers to improve caries diagnosis and management. The present review outlines the published literature of human clinical proteomics investigations on caries and extensively elucidates frequently reported salivary proteins as biomarkers. This review also discusses important aspects while designing an experimental proteomics workflow. The protein-protein interactions and the clinical relevance of salivary proteins as biomarkers for caries, together with uninvestigated domains of the discipline are also discussed critically.

Metagenomic analysis reveals ecological and functional signatures of oral phageome associated with severe early childhood caries

OBJECTIVES

Severe early childhood caries (S-ECC) is highly prevalent, affecting children's oral health. S-ECC development is closely associated with the complex oral microbial microbiome and its microorganism interactions, such as the imbalance of bacteriophages and bacteria. Till now, little is known about oral phageome on S-ECC. Therefore, this study aimed to investigate the potential role of the oral phageome in the pathogenesis of S-ECC.

METHODS

Unstimulated saliva (2 mL) was collected from 20 children with and without S-ECC for metagenomics analysis. Metagenomics sequencing and bioinformatic analysis were performed to determine the two groups' phageome diversity, taxonomic and functional annotations. Statistical analysis and visualization were performed with R and SPSS Statistics software.

RESULTS

85.7 % of the extracted viral sequences were predicted from phages, in which most phages were classified into Myoviridae, Siphoviridae, and Podoviridae. Alpha diversity decreased, and Beta diversity increased in the S-ECC phageome compared to the healthy group. The abundance of Podoviridae phages increased, and the abundance of Inoviridae, Herelleviridae, and Streptococcus phages decreased in the S-ECC group. Functional annotation revealed increased annotation on glycoside hydrolases and nucleotide metabolism, decreased glycosyl transferases, carbohydrate-binding modules, and biogenic metabolism in the S-ECC phageome.

CONCLUSIONS

Metagenomic analysis revealed reduced Streptococcus phages and significant changes in functional annotations within the S-ECC phageome. These findings suggest a potential weakening of the regulatory influence of oral bacteria, which may indicate the development of innovative prevention and treatment strategies for S-ECC. These implications deserve further investigation and hold promise for advancing our understanding and management of S-ECC.

CLINICAL SIGNIFICANCE

The findings of this study indicate that oral phageomes are associated with bacterial genomes and metabolic processes, affecting the development of S-ECC. The reduced modulatory effect of the oral phageome in counteracting S-ECC's cariogenic activity suggests a new avenue for the prevention and treatment of S-ECC.

Effect of Probiotic Supplements on the Oral Microbiota-A Narrative Review

Data from systematic reviews and meta-analyses show that probiotics positively impact clinical parameters of oral diseases such as gingivitis, dental caries, and periodontitis. However, the working mechanism of probiotics is not fully understood, but is hypothesized to be mediated by direct and indirect interactions with the oral microbiota and the human host. In the present narrative review, we focused on the microbiological effect of probiotic supplements based on data retrieved from randomized clinical trials (RCTs). In addition, we assessed to what extent contemporary molecular methods have been employed in clinical trials in the field of oral probiotics. Multiple RCTs have been performed studying the potential effect of probiotics on gingivitis, dental caries, and periodontitis, as evaluated by microbial endpoints. In general, results are conflicting, with some studies reporting a positive effect, whereas others are not able to record any effect. Major differences in terms of study designs and sample size, as well as delivery route, frequency, and duration of probiotic consumption, hamper comparison across studies. In addition, most RCTs have been performed with a limited sample size using relatively simple methods for microbial identification, such as culturing, qPCR, and DNA-DNA checkerboard, while high-throughput methods such as 16S sequencing have only been employed in a few studies. Currently, state-of-the-art molecular methods such as metagenomics, metatranscriptomics, and metaproteomics have not yet been used in RCTs in the field of probiotics. The present narrative review revealed that the effect of probiotic supplements on the oral microbiota remains largely uncovered. One important reason is that most RCTs are performed without studying the microbiological effect. To facilitate future systematic reviews and meta-analyses, an internationally agreed core outcome set for the reporting of microbial endpoints in clinical trials would be desirable. Such a standardized collection of outcomes would most likely improve the quality of probiotic research in the oral context.

Advances in Electrochemical Biosensors for the Detection of Common Oral Diseases

Limiting and preventing oral diseases remains a major challenge to the health of populations around the world, so finding ways to detect early-stage diseases (e.g., caries, periodontal disease, and oral cancer) and aiding in their prevention has always been an important clinical treatment concept. The development and application of electrochemical detection technology can provide important support for the early detection and non-invasive diagnosis of oral diseases and make up for the shortcomings of traditional diagnostic methods, which are highly sensitive, non-invasive, cost-effective, and less labor-intensive. It detects specific disease markers in body fluids through electrochemical reactions, discovers early warning signals of diseases, and realizes rapid and reliable diagnosis. This paper comprehensively summarizes the development and application of electrochemical biosensors in the detection and diagnosis of common oral diseases in terms of application platforms, sensing types, and disease detection, and discusses the challenges faced by electrochemical biosensors in the detection of oral diseases as well as the great prospects for future applications, in the hope of providing important insights for the future development of electrochemical biosensors for the early detection of oral diseases.

Application of omics technologies in cariology research: A critical review with bibliometric analysis

OBJECTIVES

To review the application of omics technologies in the field of cariology research and provide critical insights into the emerging opportunities and challenges.

DATA & SOURCES

Publications on the application of omics technologies in cariology research up to December 2022 were sourced from online databases, including PubMed, Web of Science and Scopus. Two independent reviewers assessed the relevance of the publications to the objective of this review.

STUDY SELECTION

Studies that employed omics technologies to investigate dental caries were selected from the initial pool of identified publications. A total of 922 publications with one or more omics technologies adopted were included for comprehensive bibliographic analysis. (Meta)genomics (676/922, 73 %) is the predominant omics technology applied for cariology research in the included studies. Other applied omics technologies are metabolomics (108/922, 12 %), proteomics (105/922, 11 %), and transcriptomics (76/922, 8 %).

CONCLUSION

This study identified an emerging trend in the application of multiple omics technologies in cariology research. Omics technologies possess significant potential in developing strategies for the detection, staging evaluation, risk assessment, prevention, and management of dental caries. Despite the numerous challenges that lie ahead, the integration of multi-omics data obtained from individual biological samples, in conjunction with artificial intelligence technology, may offer potential avenues for further exploration in caries research.

CLINICAL SIGNIFICANCE

This review presented a comprehensive overview of the application of omics technologies in cariology research and discussed the advantages and challenges of using these methods to detect, assess, predict, prevent, and treat dental caries. It contributes to steering research for improved understanding of dental caries and advancing clinical translation of cariology research outcomes.

Oral microbiome characteristics in patients with pediatric solid tumor

Background

Pediatric solid tumor, the abnormal proliferation of solid tissues in children resulting in the formation of tumors, represent a prevailing malignant ailment among the younger population. Extensive literature highlights the inseparable association linking oral microbiome and adult tumors, but due to differences in age of onset, characteristics of onset, etc., there are many differences between Pediatric solid tumors and adult tumors, and therefore, studying the relationship between Pediatric solid tumor and the oral microbiota is also essential.

Methods

To unravel the distinct characteristics of the oral microbiota within Pediatric solid tumor patients, 43 saliva samples, encompassing 23 Pediatric solid tumor patients and 20 healthy controls, were diligently procured. A meticulous screening process ensued, and conducted microbial MiSeq sequencing after screening.

Results

We documented the oral microbiome attributes among pediatric diagnosed with solid tumors (PST), and meanwhile, we observed a significant trend of decreased oral microbiota diversity in the pediatric solid tumor group. There were notable disparities in microbial communities observed between the two groups, 18 genera including Veillonellaceae, Firmicutes unclassified, Coriobacteriia, Atopobiaceae, Negativicutes, were significantly enriched in PST patients, while 29 genera, including Gammaproteobacteria, Proteobacteria, Burkholderiales, Neisseriaceae, were dominant in the HCs group. It was found that PST group had 16 gene functions, including Amino acid metabolism, Cysteine and methionine metabolism, Photosynthesis antenna proteins, Arginine and proline metabolism, and Aminoacyl tRNA biosynthesi, were significantly dominant, while 29 gene functions that prevailed in HCs.

Conclusion

This study characterized the oral microbiota of Pediatric solid tumor patients for the first time, and importantly, targeted biomarkers of oral microbiota may serve as powerful and non-invasive diagnostic tools for pediatric solid tumor patients.

Estimation and Association of Total Protein Concentration with Early Childhood Caries in 3-6-year-old Children: A Randomized Clinical Trial

Background and objective

Caries is a common problem witnessed in children, early childhood caries (ECC) is the most predominant chronic disease which not only leads to distress and pain but also poor quality of life, thus affecting the overall well-being of children. Salivary protein plays a vital part in monitoring health status or disease. It was stated that the salivary proteins could regulate the equilibrium of oral health, preserve a stable ecosystem, and constrain the growth of cariogenic bacteria.

Aim

The aim of this study is to estimate the total protein concentration in saliva and its correlation to ECC.

Materials and methods

A total of 20 patients with ECC in the age-group of 3-6 years were selected as the experimental group and 20 patients without caries for the control group. Unstimulated saliva samples were collected and subjected to spectrophotometry. The data obtained was subjected to statistical analysis. Independent student's t-test was used for the comparison of mean salivary pH between the caries group and the control group. Mann-Whitney test was used for a comparison of salivary total protein concentrations between the two groups.

Results

The mean pH of the carious group showed a statistically significant slightly lower value than that of the noncarious group. On the contrary, the mean total protein concentration of the carious group presented a statistically significant higher value than that of the noncarious group. Age-wise comparison of mean salivary proteins in the carious group and the noncarious group showed an increase in the protein concentration in the children aged 4 years or younger.

Conclusion

Based on the results of this study, it can be concluded that there is a strong association between the total protein concentration in saliva and ECC. There exists a significant increase in the total protein concentration in children with ECC. As age increases, total protein concentration decreases with age.

Clinical significance

Total protein concentration and particular protein estimation and quantification help us in assessing the risk of caries in children at the earliest and prevention of caries through preventive measures. Estimation of total salivary protein concentration in children can be a marker for ECC in children.

How to cite this article

Thimmegowda U, Pai S, Chikkanarasaiah N, et al. Estimation and Association of Total Protein Concentration with Early Childhood Caries in 3-6-year-old Children: A Randomized Clinical Trial. Int J Clin Pediatr Dent 2024;17(1):36-40.

Evaluation of Changes in Oral Microflora in Children with Early Childhood Caries after Full Mouth Rehabilitation

Aim

To evaluate the change in microflora in children suffering from severe early childhood caries (ECC) after full mouth rehabilitation.

Materials and methods

A total of 60 children, aged 3-5 years suffering from severe ECC who fulfilled the inclusion and exclusion criteria were included in the study. Pooled plaque samples were taken and subjected to quantitative reverse transcriptase polymerase chain reaction (PCR) to obtain baseline mean values of Streptococcus mutans (S. mutans), Streptococcus sobrinus (S. sobrinus), Candida albicans (C. albicans), and Candida dubliniensis (C. dubliniensis) before full mouth rehabilitation was done under general anesthesia. Posttreatment samples were collected at 6, 12, and 18 months. Wilcoxon signed-rank test was used to compare the mean values of S. mutans, S. sobrinus, C. albicans, and C. dubliniensis before and after full mouth rehabilitation.

Results

A total of 60 patients recruited for the study were present at the follow-up at 6 and 12 months. At 18 months, 55 patients returned, and five were lost due to follow-up. A statistically significant reduction was seen in all microorganisms at 6, 12, and 18 months compared to baseline values. At 18 months a slight increase in S. mutans, S. sobrinus, and C. albicans was seen. C. dubliniensis was not detected in any cases after full mouth rehabilitation. Caries recurrence was seen in four patients at 18 months.

Conclusion

Significant reduction of S. mutans, S. sobrinus, C. albicans, and C. dubliniensis was seen at 6, 12, and 18 months. A complete reduction of only C. dubliniensis was seen. A significant but not permanent reduction of S. mutans, S. sobrinus, and C. albicans. Caries recurrence was seen in 7.27% of patients at 18 months.

How to cite this article

Mathew MG, Jeevanandan G, Rathod NN. Evaluation of Changes in Oral Microflora in Children with Early Childhood Caries after Full Mouth Rehabilitation. Int J Clin Pediatr Dent 2024;17(1):21-25.

Microbiological Evaluation of Herbal Extracts against Candida albicans in Early Childhood Caries Patients: An In Vitro Study

Purpose

The current literature proposes a probable role of Candida albicans (C. albicans) in its etiopathogenesis in early childhood caries (ECC). This study aimed to isolate C. albicans species in children with and without ECC and compare the antifungal efficacy of neem, miswak, cinnamon, clove, stevia, and ketoconazole. This study also aimed to assess and compare salivary pH in children with and without ECC.

Materials and methods

A total of 60 children were included in the study, who were divided into two groups-group I (children with ECC) and group II (children without ECC). Plaque samples were collected and streaked on Sabouraud dextrose agar (SDA). C. albicans isolates were evaluated, and their susceptibility to herbal agents was tested and compared. Saliva samples were collected, and salivary pH was tested and compared.

Results

The presence of C. albicans was significantly higher in group I (76.7%) as compared to group II (23.3%). The mean zone of inhibition for neem was 4.9 mm, whereas, for miswak, it was 4.5 mm; for cinnamon, 9.3 mm; for clove, 3.8 mm; for stevia, 10.9 mm; and for ketoconazole it was 21.09 mm. The mean salivary pH for group I was 6.7, and that for group II was 7.3.

Conclusion

Candida albicans (C. albicans) carriage in children with ECC was significantly higher than in children without ECC. All herbal agents showed significant antifungal activity, with stevia showing the highest activity. The average salivary pH of children without ECC was slightly higher than that of children with ECC.

How to cite this article

Siddaiah SB, Sinha S, BR A. Microbiological Evaluation of Herbal Extracts against Candida albicans in Early Childhood Caries Patients: An In Vitro Study. Int J Clin Pediatr Dent 2024;17(1):26-30.

Salivary microbiome in kidney diseases: A narrative review

Many research has been conducted since the microbiota's discovery that have focused on the role it plays in health and disease. Microbiota can be divided into categories like intestinal, oral, respiratory, and skin microbiota based on the specific localized areas. To maintain homeostasis and control immunological response, the microbial populations live in symbiosis with the host. On the other hand, dysbiosis of the microbiota can cause diseases including kidney diseases and the deregulation of body functioning. We discuss the current understanding of how various kidney diseases are caused by the salivary microbiome (SM) in this overview. First, we review the studies on the salivary microbiota in diverse clinical situations. The importance of the SM in diabetic kidney disease, chronic kidney disease, membranous nephropathy, and IgA nephropathy is next highlighted. We conclude that the characteristics of the SM of patients with various kidney diseases have revealed the potential of salivary microbial markers as noninvasive tool for the detection of various kidney diseases.

The Role of Dysbiotic Oral Microbiota in Cardiometabolic Diseases: A Narrative Review

Over the past decade, there have been significant advancements in the high-flow analysis of "omics," shedding light on the relationship between the microbiota and the host. However, the full recognition of this relationship and its implications in cardiometabolic diseases are still underway, despite advancements in understanding the pathophysiology of these conditions. Cardiometabolic diseases, which include a range of conditions from insulin resistance to cardiovascular disease and type 2 diabetes, continue to be the leading cause of mortality worldwide, with a persistently high morbidity rate. While the link between the intestinal microbiota and cardiometabolic risks has been extensively explored, the role of the oral microbiota, the second-largest microbiota in the human body, and specifically the dysbiosis of this microbiota in causing these complications, remains incompletely defined. This review aims to examine the association between the oral microbiota and cardiometabolic diseases, focusing on the dysbiosis of the oral microbiota, particularly in periodontal disease. Additionally, we will dive into the mechanistic aspects of this dysbiosis that contribute to the development of these complications. Finally, we will discuss potential prevention and treatment strategies, including the use of prebiotics, probiotics, and other interventions.

Comparison of oral cavity protein abundance among caries-free and caries-affected individuals-a systematic review and meta-analysis

Objective

Some salivary proteins seem to be differently abundant among caries-free (CF) and caries-affected (CA) individuals, but previous results are contradictory precluding that definitive conclusion be drawn. A pooled analysis of the available evidence may provide more robust data on identifying oral cavity protein patterns among CF and CA individuals. This systematic review and meta-analysis (PROSPERO CRD42021269079) aimed to compare the oral cavity protein abundance among caries-free and caries-affected individuals.

Methods

This study was conducted following PRISMA guidelines. PubMed, Embase, and Web of Science databases were systematically assessed (up to February 2023) to retrieve clinical studies written in English, German, or in Latin-based languages that compared the oral cavity protein abundance among CF and CA individuals. Data extraction and methodological quality assessment (NIH guidelines) were independently performed by two investigators. Qualitative synthesis was performed from all included studies and meta-analysis was performed using a random-effects model with inverse variance for studies that reported the concentration of proteins or enzymatic activity. Standardized mean difference (SMD) with respective 95% confidence interval (CI) were calculated for each outcome.

Results

A total of 90 studies (two cohort and 88 cross-sectional designs) of more than 6,000 participants were selected for data extraction, being the quality of evidence graded as "fair" for most of them. The oral cavity of CF individuals presented lower total protein concentration [SMD = 0.37 (95% CI: 0.07-0.68; 18 studies)], lower total antioxidant capacity [SMD = 1.29 (95% CI: 0.74-1.85); 17 studies], and lower carbonic anhydrase activity [SMD = 0.83 (95% CI: 0.58-1.09); three studies], whereas CA individuals presented lower carbonic anhydrase concentration [SMD = -0.66 (95% CI: -1.00 to -0.32); three studies], urease [SMD = -0.95 (IC 95%: -1.72 to -0.17); four studies], and arginine deiminase system [SMD = -2.07 (95% CI: -3.53 to -0.62); three studies] activities. Antimicrobial peptides, secretory immunoglobulin-A concentrations and alpha-amylase activity were similar among individuals.

Conclusion

Differences on oral cavity protein abundance were observed among CF and CA individuals. These data indicate some protein patterns for the oral health and dental caries conditions. Even when statistically significant, some of the results were not very consistent. Cohort studies need to be conducted to validate these results.

Predictors of Caries Risk among Egyptian Children Attending Pediatric Dental Clinics at a University Hospital

Background

Dental caries is the most prevalent dental disease. The external validity of the available caries risk assessment (CRA) tools is not established, especially among pediatric population.

Objectives

To assess caries risk using the caries management by risk assessment (CAMBRA) protocol among Egyptian children aged 3-12 years and suggest variables that could potentially be used to develop a simpler CRA model.

Materials and Methods

For this cross-sectional study, we recruited 320 children aged 3 to <6 years (Group I) and 320 children aged 6-12 years (Group II). CAMBRA was used to collect data about disease indicators, biological and environmental factors, and protective factors among study participants. Each child was examined clinically to collect data about past caries experiences and to measure plaque scores.

Results

The risk of caries was high in 92.5% of Group I and 83.4% of Group II participants. The overall dmft was 5.71 ± 3.18 for Group I and 4.78 ± 2.53 for Group II. In Group I, a significant positive relation was found between the overall mean caries risk score and past caries experience (dmft; r = 0.344, P < 0.001) and mean plaque index (r = 0.463, P < 0.001). In Group II, a significant positive relation was found between the overall mean caries risk score and dmft score (r = 0.511, P < 0.001), S. mutans count (r = 234, P < 0.001), Lactobacilli count (r = 0.316, P < 0.001), and plaque index (r = 0.463, P < 0.001). Participants' age, parents' education, and parents' occupation had a negative significant effect on the overall mean caries risk score.

Conclusion

This study suggests predictors that can be used in the development of a new CRA model for children aged 3-12 years.

Prediction of Future Caries in 1-Year-Old Children via the Salivary Microbiome

Dental caries is the most common chronic disease in children that causes negative effects on their health, development, and well-being. Early preventive interventions are key to reduce early childhood caries prevalence. An efficient strategy is to provide risk-based targeted prevention; however, this requires an accurate caries risk predictor, which is still lacking for infants before caries onset. We aimed to develop a caries prediction model based on the salivary microbiome of caries-free 1-y-old children. Using a nested case-control design within a prospective cohort study, we selected 30 children based on their caries status at 1-y follow-up (at 2 y old): 10 children who remained caries-free, 10 who developed noncavitated caries, and 10 who developed cavitated caries. Saliva samples collected at baseline before caries onset were analyzed through 16S rRNA gene sequencing. The results of β diversity analysis showed a significant difference in salivary microbiome composition between children who remained caries-free and those who developed cavitated caries at 2 y old (analysis of similarities, Benjamini-Hochberg corrected, P = 0.042). The relative abundance of Prevotella nanceiensis, Leptotrichia sp. HMT 215, Prevotella melaninogenica, and Campylobacter concisus in children who remained caries-free was significantly higher than in children who developed cavitated caries (Wilcoxon rank sum test, P = 0.024, 0.040, 0.049, and 0.049, respectively). These taxa were also identified as biomarkers for children who remained caries-free (linear discriminant analysis effect size, linear discriminant analysis score = 3.69, 3.74, 3.53, and 3.46). A machine learning model based on these 4 species distinguished between 1-y-old children who did and did not develop cavitated caries at 2 y old, with an accuracy of 80%, sensitivity of 80%, and specificity of 80% (area under the curve, 0.8; 95% CI, 44.4 to 97.5). Our findings suggest that these salivary microbial biomarkers could assist in predicting future caries in caries-free 1-y-old children and, upon validation, are promising for development into an adjunctive tool for caries risk prediction for prevention and monitoring.

Precision Medicine in Oral Health and Diseases: A Systematic Review

Precision medicine (PM) is personalized medicine that can develop targeted medical therapies for the individual patient, in which "omics" sciences lead to an integration of data that leads to highly predictive models of the functioning of the individual biological system. They enable rapid diagnosis, assessment of disease dynamics, identification of targeted treatment protocols, and reduction of costs and psychological stress. "Precision dentistry" (DP) is one promising application that need further investigation; the purpose of this paper is therefore to give physicians an overview of the knowledge they need to enhance treatment planning and patient response to therapy. A systematic literature review was conducted on the PubMed, Scopus, and Web of Science databases by analyzing the articles examining the role of precision medicine in dentistry. PM aims to shed light on cancer prevention strategies, by identifying risk factors, and on malformations such as orofacial cleft. Another application is pain management by repurposing drugs created for other diseases to target biochemical mechanisms. The significant heritability of traits regulating bacterial colonization and local inflammatory responses is another result of genomic research, and is useful for DP in the field of caries and periodontitis. This approach may also be useful in the field of orthodontics and regenerative dentistry. The possibility of creating an international network of databases will lead to the diagnosis, prediction, and prevention of disease outbreaks, providing significant economic savings for the world's health care systems.

Quantitative analysis of salivary and biofilm bacteria associated with cavitated and non-cavitated carious lesions in pre-school children

OBJECTIVE

To quantify and compare Streptococcus mutans (S. mutans) and Lactobacillus fermentum (L. fermentum) in saliva and biofilm of caries-free children to those with cavitated and non-cavitated lesions.

DESIGN

One hundred and thirty-five 3-4 years old children were grouped (n = 45 in each group) according to their caries status: Clinical examination was done by a calibrated examiner. Biofilm and saliva were collected to quantify the microorganisms using qRT-PCR. The decayed-missing-filled surfaces (dmfs) was calculated by adding the number of decayed (ICDAS-II score 3-6), filled (ICDAS-II score 7 and 8) and missing (ICDAS-II score 9) surfaces due to caries. The correlation between the bacterial amounts and the number of carious surfaces was evaluated using Spearman's correlation coefficient. The levels and proportions of the microorganisms were compared using the Kruskal-Wallis test at an α-level of 0.05.

RESULTS

The quantity of S. mutans and L. fermentum was significantly higher in saliva and biofilm of children with cavitated lesions, followed by those with non-cavitated lesions and the lowest in caries-free children. Also, salivary and biofilm S. mutans, along with biofilm L. fermentum levels, significantly correlated with the number of non-cavitated surfaces; while salivary and biofilm S. mutans and L. fermentum levels significantly correlated with the number of cavitated surfaces. Additionally, dmfs scores significantly correlated with the salivary and biofilm S. mutans and L. fermentum levels.

CONCLUSIONS

S. mutans and L. fermentum in saliva and biofilm samples are associated with caries lesion severity.

The abundance of lysozyme, lactoferrin and cystatin S in the enamel pellicle of children - Potential biomarkers for caries?

OBJECTIVE

In this study, the abundance of the protective salivary proteins lysozyme, lactoferrin, and cystatin S was quantified in the in situ formed pellicle of caries-free and caries-active children to determine whether they may be possible biomarkers for caries.

DESIGN

Pellicle formation was performed in situ for 10 min on ceramic specimens from the oral cavity of children (5-8 years) with caries (n = 17) and without evidence of caries (n = 17). Additionally, unstimulated saliva was collected. Levels of lysozyme, lactoferrin, and cystatin S were measured in desorbed pellicle eluates and saliva using ELISA.

RESULTS

No statistically significant differences were found in the occurrence of cystatin S and lysozyme in saliva and pellicle between caries-active and caries-free children. However, significantly higher amounts of lactoferrin were detected in the pellicle of caries-active children.

CONCLUSION

The protective salivary protein lactoferrin may be a biomarker for caries susceptibility in children.

Salivary Diagnostics in Pediatrics and the Status of Saliva-Based Biosensors

Salivary biomarkers are increasingly being used as an alternative to diagnose and monitor the progression of various diseases due to their ease of use, on site application, non-invasiveness, and most likely improved patient compliance. Here, we highlight the role of salivary biosensors in the general population, followed by the application of saliva as a diagnostic tool in the pediatric population. We searched the literature for pediatric applications of salivary biomarkers, more specifically, in children from 0 to 18 years old. The use of those biomarkers spans autoimmune, developmental disorders, oncology, neuropsychiatry, respiratory illnesses, gastrointestinal disorders, and oral diseases. Four major applications of salivary proteins as biomarkers are: (1) dental health (caries, stress from orthodontic appliances, and gingivitis); (2) gastrointestinal conditions (eosinophilic esophagitis, acid reflux, appendicitis); (3) metabolic conditions (obesity, diabetes); and (4) respiratory conditions (asthma, allergic rhinitis, small airway inflammation, pneumonia). Genomics, metabolomics, microbiomics, proteomics, and transcriptomics, are various other classifications for biosensing based on the type of biomarkers used and reviewed here. Lastly, we describe the recent advances in pediatric biosensing applications using saliva. This work guides scientists in fabricating saliva-based biosensors by comprehensively overviewing the potential markers and techniques that can be employed.

Oral hygiene practices in nurseries (0-3 years) in the cities of Pavia and Vigevano

Aim

This study was conducted to evaluate attention to and knowledge of oral care in children aged 0-3 years, on the basis of data collected from early years educators working with this age group. Information was also collected about the oral hygiene practices adopted in nurseries and the types of food provided, with the aim of increasing knowledge and raising awareness of this topic.

Materials and methods

A questionnaire was created using the "Google Forms" program and sent to all the 47 nurseries in the city of Pavia and Vigevano.

Results

Twenty establishments agreed to take part in the research. Assessment of knowledge and of awareness of oral care among early years educators caring for children in the age range 0-3 years revealed variability and some confusion. The results showed a general lack of attention to oral care in the period before the milk teeth appear, as well as limited use of gauze swabs. There was generally some use of educational play focusing on this issue, albeit not daily across all the nurseries participating in the survey. Nurseries rarely had the support of a professional dental hygienist to raise awareness among early years educators and parents.

Conclusions

The findings obtained through this study indicate that, in the area surveyed, there is a lack of widespread knowledge and awareness of oral prevention in young children, and of the oral hygiene maintenance techniques to use in this age group. This suggests a need to develop preventive protocols to improve knowledge and awareness of children's oral health among the adults who care for them.

INDICATORS OF DENTAL HEALTH AND LOCAL IMMUNITY IN YOUNG ADULTS WHO HAVE SUFFERED FROM CORONAVIRUS INFECTION

OBJECTIVE

The aim: To determine the dental status and state of local immunity in young adults who have suffered from the coronavirus disease.

PATIENTS AND METHODS

Materials and methods: The main group consisted of 30 people aged 20-22 years, who suffered from the coronavirus infection Covid19 6.1±1.2 months ago. The comparison group included 20 people who did not have a coronavirus infection. The control group consisted of 35 people, randomized by age and sex, who did not have signs of caries and periodontal tissue disease and did not have coronavirus disease. All patients were examined for dental status and local immunity.

RESULTS

Results: The analysis of indicators of dental status revealed the possibility of the existence of a relationship between the signs of acute SARS-Cov2 viral infection and the development of caries and periodontal tissue diseases. Significant changes in the local immunity of the oral cavity were found in the examined patients, which had a pathogenetic influence on the development and progression of caries and periodontal tissue diseases: a significant increase in the level of Ig G, as well as a probable decrease in the concentration of SIg A relative to the comparison group, a probably higher normative value of pathogenic small- and medium-molecular CICs with a significant decrease in the level of physiological large-sized CICs relative to the comparison group, a decrease in the content of anti-inflammatory IL-4, as well as increased concentration of pro-inflammatory cytokines.

CONCLUSION

Conclusions: Young adults who have suffered a coronavirus infection during the last 6 months have significantly higher caries prevalence, bleeding index, PMA index and hygiene index, halitosis, which indicates deeper tissue damage and tooth pathology with the formation of dentition defects than in the comparison group. Indicators of local immunity of the oral fluid have a deep and specific character.

Prediction model for early childhood caries risk based on behavioral determinants using a machine learning algorithm

BACKGROUND

An easily accessible caries risk prediction model (CRPM) based on nonbiological predictors is lacking. Developing a CRPM for community screening is essential for children's dental health promotion by a public health approach.

OBJECTIVE

This study aimed to develop and validate a caries risk prediction model (CRPM) for children using a machine learning algorithm based on dental care behavioral factors and other nonbiological factors using a 3-month multicenter cohort.

METHODS

Children aged 12 months to 60 months were recruited at three primary care settings and three kindergartens in Chengdu, China. Dental examination was conducted for all enrolled children by calibrated pediatric dentists at baseline and three months later. All parents of the enrolled children were asked to complete a questionnaire with dental-related information. Machine learning algorithms, including random forest, logistic regression, and adaptive boosting, were used to develop a prediction model. Sensitivity, specificity, accuracy, precision, negative predictive value and F-score were reported to estimate the internal validation of the models.

RESULTS

A total of 481 out of 745 children without a history of caries experience at baseline remained for analysis. In the total sample population, 236 (49.1%) children were female, and the mean age was 31.2 months. During the follow-up exams, 66 (13.6%) children had new-onset caries. The child's age, height, weight, family caries status, brush teeth two minutes per time, fluoride toothpaste usage, brushing twice per day, parental monitoring brushing teeth, mother delivery method, brushing child's teeth every day, child number counts, and night feeding frequency in the last month were measured and included in a prediction model. Of the prediction models, the highest area under the curve of RF was 0.91 (95% CI: 0.87- 0.94), followed by 0.86 (95% CI: 0.81-0.91) of LR and 0.81 (95% CI: 0.76-0.86) of AdaBoost.

CONCLUSION

In this CRPM, new onset of dental caries in three months among children aged < 60 months could be predicted by answering twelve nonbiological questions. A good model performance was shown within the internal validation. Dental home care could be improved by referring the CRPM result before new caries onset.

Effectiveness of Mouthwash-Containing Silver Nanoparticles on Cariogenic Microorganisms, Plaque Index, and Salivary pH in A Group of Saudi Children

Objectives:

To compare the effectiveness of Silver nanoparticles (AgNPs) and Chlorhexidine (CHX) mouthwash on Streptococcus mutans (S. mutans), Lactobacillus spp., and Candida albicans (C. albicans) counts O’Leary plaque index (O’Leary PI) scores, and salivary pH levels among children.

Materials and Methods:

The study sample consisted of 117 eligible participants aged 12–18 years. They were divided into control, CHX, and AgNPs groups, with 39 subjects per group. The log10 salivary microbial counts, O’Leary PI, and salivary pH values were recorded and statistically analyzed at baseline and the 28th day. Descriptive statistics were presented as the mean ± standard deviation. In addition, the analyses of variance (ANOVA) and Tukey posthoc test were implemented. The p-value ≤ 0.05 denotes a significant difference between the two points.

Results:

AgNPs and CHX mouthwash were found to have significantly reduced salivary microbial counts and O’Leary PI scores. The salivary pH levels notably increased on the 28th day (p-value < 0.001). All measured outcomes demonstrated notable effects, with the greatest observed for the CHX group, followed by the AgNPs group, and finally, the control group.

Conclusion:

Chlorhexidine and AgNPs mouthwash effectively reduced the cariogenic microbial count and dental plaque and improved the salivary pH values. AgNPs mouthwash may be used as an adjunctive measure to prevent dental caries.

Expert consensus on clinical management for early childhood caries

Early childhood caries (ECC) is the most prevalent chronic oral disease and one of the worldwide public health problems of great urgency for children. ECC can affect children's teeth, dentition, craniomaxillofacial, and general health and development. Therefore, through dental caries etiologies and caries risk assessment, patient-centered, personalized planning and a combination of prevention and treatment should be implemented in the clinical management for ECC. Periodic and continuous cycle management can only be accomplished with the cooperation of medical staff, children, and their guardians. This expert consensus will expound the clinical management of ECC in the following aspects: caries risk assessment, early clinical prevention, treatment strategies, and postoperative management.

Expert consensus on early childhood caries management

Early childhood caries (ECC) is a significant chronic disease of childhood and a rising public health burden worldwide. ECC may cause a higher risk of new caries lesions in both primary and permanent dentition, affecting lifelong oral health. The occurrence of ECC has been closely related to the core microbiome change in the oral cavity, which may be influenced by diet habits, oral health management, fluoride use, and dental manipulations. So, it is essential to improve parental oral health and awareness of health care, to establish a dental home at the early stage of childhood, and make an individualized caries management plan. Dental interventions according to the minimally invasive concept should be carried out to treat dental caries. This expert consensus mainly discusses the etiology of ECC, caries-risk assessment of children, prevention and treatment plan of ECC, aiming to achieve lifelong oral health.

Oralbiotica/Oralbiotics: The Impact of Oral Microbiota on Dental Health and Demineralization: A Systematic Review of the Literature

The oral microbiota plays a vital role in the human microbiome and oral health. Imbalances between microbes and their hosts can lead to oral and systemic disorders such as diabetes or cardiovascular disease. The purpose of this review is to investigate the literature evidence of oral microbiota dysbiosis on oral health and discuss current knowledge and emerging mechanisms governing oral polymicrobial synergy and dysbiosis; both have enhanced our understanding of pathogenic mechanisms and aided the design of innovative therapeutic approaches as ORALBIOTICA for oral diseases such as demineralization. PubMed, Web of Science, Google Scholar, Scopus, Cochrane Library, EMBEDDED, Dentistry & Oral Sciences Source via EBSCO, APA PsycINFO, APA PsyArticles, and DRUGS@FDA were searched for publications that matched our topic from January 2017 to 22 April 2022, with an English language constraint using the following Boolean keywords: ("microbio*" and "demineralization*") AND ("oral microbiota" and "demineralization"). Twenty-two studies were included for qualitative analysis. As seen by the studies included in this review, the balance of the microbiota is unstable and influenced by oral hygiene, the presence of orthodontic devices in the oral cavity and poor eating habits that can modify its composition and behavior in both positive and negative ways, increasing the development of demineralization, caries processes, and periodontal disease. Under conditions of dysbiosis, favored by an acidic environment, the reproduction of specific bacterial strains increases, favoring cariogenic ones such as Bifidobacterium dentium, Bifidobacterium longum, and S. mutans, than S. salivarius and A. viscosus, and increasing of Firmicutes strains to the disadvantage of Bacteroidetes. Microbial balance can be restored by using probiotics and prebiotics to manage and treat oral diseases, as evidenced by mouthwashes or dietary modifications that can influence microbiota balance and prevent or slow disease progression.

Oral fluid immunological characteristics in children with congenital cleft palate and a postoperative defect

Relevance. The lack of anatomical differentiation between the oral cavity and the nasal cavity in children with congenital cleft palate leads to the deterioration of saliva characteristics affecting dental and periodontal disease progression. The oral fluid immunological profile may provide information about the nature of the inflammatory processes and changes in the reaction to the ongoing therapy.

Material and methods. The article presents the results of the oral fluid enzyme immunoassay in 109 children aged 6-12 years with congenital cleft palate and a postoperative defect and in 50 practically healthy children of the same age. The study determined the levels of pro-inflammatory (IL-1β, IL-6, TNF-α) and anti-inflammatory (IL-4, IL-10) cytokines and secretory immunoglobulin sIgA in the oral fluid by enzyme-linked immunosorbent assay.

Results. The study of children aged 6-12 years with congenital cleft palate and a postoperative defect revealed hyperstimulation of oral fluid pro-inflammatory (IL-1β, IL-6, TNF-α) and anti-inflammatory (IL-4, IL-10) cytokines and a decrease in secretory immunoglobulin sIgA mean level.

Conclusion. The oral fluid immunological complexes imbalance in children with congenital cleft palate and a postoperative residual defect is a progressive factor for the development and chronicity of oral inflammatory diseases.

The received data evidence the local inflammatory process and a decrease in the oral fluid local protective factors, which one must consider to develop methods for improving the condition of organs and tissues of the oral cavity in children with congenital cleft palate during preparation for surgery to eliminate the residual defect.

Taxonomic and functional alterations in the salivary microbiota of children with and without severe early childhood caries (S-ECC) at the age of 3

Background

Primary dental caries is the most prevalent oral disease among preschool children, which can cause severe damage to teeth and even affect the mental well-being of children. Various studies have demonstrated that the oral microbiome plays a pivotal role in the onset and development of dental caries. However, it remains uncertain about the key microbial markers associated with caries, owing to the limited evidence.

Methods

Fifteen S-ECC children and fifteen healthy controls were selected from three-year-old children in this study. Their clinical data and oral saliva samples were collected. Shotgun sequencing was conducted to investigate the microbial differences and the relevant functions between the two groups.

Results

We observed no apparent difference in oral microbial community diversity between the two groups. Still, at the genus/species levels, several characteristic genera/species such as Propionibacterium, Propionibacterium acidifaciens, Prevotella denticola, Streptococcus mutans and Actinomyces sp. oral taxon 448/414 increased significantly in S-ECC children, compared with the oral health group. Furthermore, we found that functional pathways involving glycolysis and acid production, such as starch and sucrose metabolism, fructose and mannose metabolism, glycolysis/gluconeogenesis, were prominently up-regulated in the high-caries group.

Conclusions

Our study showed that dental caries in children were associated with the alterations in the oral microbiota at the composition and functional levels, which may potentially inspire the exploration of microbial diagnosis or therapeutic treatments.

Caries Experience and Increment in Children Attending Kindergartens with an Early Childhood Caries Preventive Program Compared to Basic Prophylaxis Measures-A Retrospective Cohort Study

Dental caries constitutes a public health challenge. As preventive strategies are desirable, this retrospective cohort study aimed to assess the caries experience and increment in children attending kindergartens with an early childhood caries (ECC) preventive program (intervention group, IG) compared to basic prophylaxis measures (control group, CG) located in areas of different socioeconomic status (SES) within Marburg (Germany). The long-term caries experience (2009−2019) of these 3−5-year-old kindergarten children was evaluated. For the caries increment, dental records of 2019 were screened for the availability of a minimum of two dental examinations at least 8 months apart. Caries was scored according to the WHO criteria (dmf−t). The data were split by observation period (300−550 and >550 days). Overall, 135 children (Ø 3.7 years) attended IG, and 132 children (Ø 3.6 years) attended CG. After 300−550 days, no significant differences were found between both groups regarding mean caries increment and experience (p > 0.05). After >550 days, IG with low SES exhibited a high caries experience. Fluoride varnish applications could not reduce the caries increment compared to CG in the short-term but slightly decreased the long-term caries experience. Comprehensive ECC prevention measures actively involving parents are needed to overcome the caries burden.

The Composition and Functional Capacities of Saliva Microbiota Differ Between Children With Low and High Sweet Treat Consumption

Excess sugar consumption—common in youth—is associated with poor health. Evidence on the relationship between sugar consumption and the oral microbiome, however, remains scarce and inconclusive. We explored whether the diversity, composition, and functional capacities of saliva microbiota differ based on the consumption of select sugary foods and drinks (“sweet treats”). Using 16S rRNA gene sequencing, we characterized saliva microbiota from 11 to 13-year-old children who participated in the Finnish Health in Teens (Fin-HIT) cohort study. The sample comprised children in the lowest (n = 227) and highest (n = 226) tertiles of sweet treat consumption. We compared differences in the alpha diversity (Shannon, inverse Simpson, and Chao1 indices), beta diversity (principal coordinates analysis based on Bray–Curtis dissimilarity), and abundance (differentially abundant operational taxonomic units (OTUs) at the genus level) between these low and high consumption groups. We performed PICRUSt2 to predict the metabolic pathways of microbial communities. No differences emerged in the alpha diversity between low and high sweet treat consumption, whereas the beta diversity differed between groups (p = 0.001). The abundance of several genera such as Streptococcus, Prevotella, Veillonella, and Selenomonas was higher in the high consumption group compared with the low consumption group following false discovery rate correction (p < 0.05). Children with high sweet treat consumption exhibited higher proportions of nitrate reduction IV and gondoate biosynthesis pathways compared with the low consumption group (p < 0.05). To conclude, sweet treat consumption shapes saliva microbiota. Children who consume a high level of sweet treats exhibited different compositions and metabolic pathways compared with children who consume low levels of sweet treats. Our findings reveal novel insights into the relationship between sugary diets and oral microbiota.

The Crosstalk Between Saliva Bacteria and Fungi in Early Childhood Caries

Early childhood caries (ECC) is the most prevalent oral disease in children, which greatly affects the quality of life and health condition of the patients. Although co-infection of oral streptococci and fungi has been well recognized in the development of ECC, the correlation between other core members of oral mycobiome and ECC progression remains unclear. In the current study, saliva samples obtained from severe ECC (SECC), ECC, and caries-free children were collected, and both V3–V4 16S rRNA and ITS1 rRNA gene amplicon sequencing were performed to investigate the salivary bacterial and fungal profiles. Significant alteration of salivary fungal community in SECC/ECC children was observed compared with the caries-free control. The typing analysis determined the fungal community into five fungal types, which influenced the structure of salivary bacteria. By performing Spearman correlation analysis, carious phenotypes were positively related to Fusobacterium but negatively linked to Neocosmospora, and a significant correlation of cross-kingdom taxonomic pairs was identified. Our work demonstrated the interactions between oral bacteria and fungi at the community level, which may advance our knowledge on the etiological role of bacteria/fungi in the development of ECC and promote better management of this disease.

Salivary Histatin 5 Level in Women with Vaginal Candidiasis

Histatins (Hsts) are considered a prominent member of antimicrobial peptides rich in histidine, bearing antifungal activity against Candida species. Hst5 is the most effective among them. Although Hst5 is not found in the cervicovaginal fluid, it has been detected in the human serum. Saliva acts as a mirror, reflecting the cause and effect relationship between several diseases. We aimed to show the salivary Hst5 levels with vaginal candidiasis. Women in the reproductive age group (18-50 years) were enrolled in the study. Patients and controls were classified based on the presence or absence of vaginal discharge suggestive of candidiasis, respectively. Vaginal and salivary samples were collected from all the women. Vaginal samples were cultured for the growth of Candida species. Salivary samples were tested by protein electrophoresis to detect Hst5 levels, and the results were compared between the two groups. A total of 80 women were included in this study. The mean age of women in vaginal candidiasis and control groups was 34.25 ± 8.06 and 36.83 ± 7.29 years, respectively. Candida species were isolated from the vaginal samples of the patient group (34 C. albicans, 6 non-Candida albicans) but not from the control group. Hst5 levels in the patient and control group were found to be 0.0571 ± 0.003 ng/mL and 0.0641 ± 0,0031 ng/mL, respectively. Hst5 levels were found to be significantly lower in the vaginal candidiasis group (p=0.001). We conclude that decreased salivary Hst5 levels in women are associated with vaginal candidiasis. Candida infection is a cause or result of lower salivary Hst5 levels, and it may be an important finding for the etiopathogenesis, diagnosis, and treatment of the disease, but further analysis is needed.

A Mini Review: The Potential Biomarkers for Non-invasive Diagnosis of Pulpal Inflammation

For assessing the adequacy of vital pulp therapy for an inflamed pulp, the use of non-invasive diagnostic tools is necessary to avoid further damage to the teeth. Detection of biomarkers that are indicative of the inflammatory status in pulp can be a promising tool for this purpose. These biomarkers need to be reliably correlated with pulpal inflammation and to be easily detected without pulp exposure. This mini-review article aims to review biomarkers that are present in gingival crevicular fluid (GCF) in inflamed pulp conditions. Several studies have reported the availability of various biomarkers including cytokines, proteases, elastase, neuropeptides, and growth factors. Non-invasive pulpal diagnostic methods will be useful as well to determine reversibility, irreversibility, or necrosis of inflamed pulp. These types of molecular diagnoses via analyzing the proteome have revolutionized the medical field, and are one of the most promising empirical methodologies that a clinician can utilize for the proactive identification of pulpal disease.

Salivary cystatin S levels in children with early childhood caries in comparison with caries-free children; statistical analysis and machine learning

Background

Early childhood caries is the most common infectious disease in childhood, with a high prevalence in developing countries. The assessment of the variables that influence early childhood caries as well as its pathophysiology leads to improved control of this disease. Cystatin S, as one of the salivary proteins, has an essential role in pellicle formation, tooth re-mineralization, and protection. The present study aims to assess salivary cystatin S levels and demographic data in early childhood caries in comparison with caries-free ones using statistical analysis and machine learning methods.

Methods

A cross-sectional, case–control study was undertaken on 20 cases of early childhood caries and 20 caries-free children as a control. Unstimulated whole saliva samples were collected by suction. Cystatin S concentrations in samples were determined using human cystatin S ELISA kit. The checklist was collected from participants about demographic characteristics, oral health status, and dietary habits by interviewing parents. Regression and receiver operating characteristic (ROC) curve analysis were done to evaluate the potential role of cystatin S salivary level and demographic using statistical analysis and machine learning.

Results

The mean value of salivary cystatin S concentration in the early childhood caries group was 191.55 ± 81.90 (ng/ml) and in the caries-free group was 370.06 ± 128.87 (ng/ml). T-test analysis showed a statistically significant difference between early childhood caries and caries-free groups in salivary cystatin S levels (p = 0.032). Investigation of the area under the curve (AUC) and accuracy of the ROC curve revealed that the logistic regression model based on salivary cystatin S levels and birth weight had the most and acceptable potential for discriminating of early childhood caries from caries-free controls. Furthermore, using salivary cystatin S levels enhanced the capability of machine learning methods to differentiate early childhood caries from caries-free controls.

Conclusion

Salivary cystatin S levels in caries-free children were higher than the children with early childhood caries. Results of the present study suggest that considering clinical examination, demographic and socioeconomic factors, along with the salivary cystatin S levels, could be usefull for early diagnosis ofearly childhood caries in high-risk children; furthermore, cystatin S is a protective factor against dental caries.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-02016-x.

Evaluation of Serum and Salivary Iron and Ferritin Levels in Children with Dental Caries: A Meta-Analysis and Trial Sequential Analysis

Background and objective: Dental caries appears to be related to iron deficiency anemia and to low ferritin levels. In the present meta-analysis, we report salivary and serum iron and ferritin levels in children with dental caries, compared to healthy controls. Materials and methods: We searched in Web of Science, Cochrane Library, Scopus, and PubMed/Medline databases to extract studies published until 25 July 2021. We calculated mean differences (MD) and 95% confidence intervals (CI) of salivary and serum iron and ferritin levels in children with dental caries, always compared to healthy controls. In addition, we applied a trial sequential analysis (TSA). Results: A total of twelve articles covering thirteen studies were included in the meta-analysis. The pooled MD for salivary iron level was −5.76 µg/dL (p = 0.57), and −27.70 µg/dL (p < 0.00001) for serum iron level: compared to healthy controls, children with dental caries did not show different salivary iron levels, while children with caries had significantly lower serum iron levels. The pooled MD of salivary ferritin level was 34.84 µg/dL (p = 0.28), and the pooled MD of serum ferritin level was −8.95 µg/L (p = 0.04): compared to healthy controls, children with dental caries did not have different salivary iron levels, but significantly lower serum ferritin levels. Conclusions: The findings of the present meta-analysis showed that salivary levels of iron and ferritin did not differ between children with and without caries, though compared to healthy controls, children with caries had significantly lower salivary and serum iron and ferritin levels. The results are of practical and clinical importance: Possibly, iron and ferritin supplementation might prevent or attenuate dental caries in children at risk. Further, children with caries might suffer from further iron- and ferritin-related health issues. Lastly, serum blood samples, but not saliva samples inform accurately about the current iron and ferritin concentrations in children with or without caries.

Analysis of salivary proteomic biomarkers for the surveillance of changes in high-risk status of early childhood caries

Background

Early childhood caries is an urgent public health concern. The aim of this study was to investigate salivary proteomic biomarkers for the surveillance of changes in the high-risk status of early childhood caries. The process involves the screening of specific salivary peptides that were differentially expressed only under dynamic changes in individual caries status.

Methods

Stimulated whole saliva samples were collected from 28 kindergarten children aged 3–4 years in Beijing at baseline and 3 months and 6 months after baseline. A total of 68 samples were collected. In terms of their caries status and progress during the observation period, participants were divided into 3 groups; 7 in the non-caries recurrence group, 6 in the caries recurrence group, and 15 in the healthy control group. Salivary peptides that exhibited no significant differences in cross-sectional comparisons between different groups of caries status but only expressed differentially along with dynamic changes of individual caries were screened using the technique of magnetic beads combined with matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS). The technique of liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) was employed to identify the proteins from which these peptides were derived.

Results

We found two salivary peptides differentially expressed only under dynamic changes in individual caries status in the above comparisons; mass-to-charge ratio (m/z) values of the two peptides were 1045.9 and 2517.6, respectively (P < 0.05). Principal component analysis (PCA) and the decision tree model based on these two peptides showed an acceptable distinguishing ability for changes in the high-risk status of early childhood caries. The source proteins of the two peptides with m/z values of 1045.9 and 2517.6 were identified as submandibular gland androgen regulatory protein 3B (SMR-3B) and mucin-7, respectively.

Conclusions

Two proteins in children’s saliva, namely SMR-3B and mucin-7, have the potentiality to serve as candidate biomarkers for dynamic surveillance of changes in high-risk status of early childhood caries.

A Two-Year Longitudinal Study of the Effectiveness of the CRT® Bacteria Test in Evaluating Caries Risk in Three-Year-Old Children

Objective

To study the correlation between the level of infection with Streptococcus mutans (SM) and lactobacilli (LB) in saliva with existing status and the development of primary dental caries in 3-year-old children and to evaluate the results of CRT^® bacteria as a Caries Risk Test.

Methods

A total of 140 3-year-old children were selected for the study. Oral examination was conducted and the levels of infection with SM and LB in saliva were measured using a CRT^® bacteria test. Oral reexamination was conducted after two years. The prevalence rate of caries, the decayed-missing-filled tooth (dmft) and decayed-missing-filled surface (dmfs) indices, and Caries Severity Index (CSI) were calculated at the start and end of the two years. The indices were statistically analyzed.

Results

The caries prevalence rate, dmft, dmfs, and CSI increased with increasing levels of CRT-SM and CRT-LB at the start and end of the two years; the increases in dmft, dmfs, and CSI over the period were consistent with the increases in CRT-SM and CRT-LB levels, with all differences being highly statistically significant. The increase in caries prevalence rate over the two years was not statistically different for different CRT-SM and CRT-LB levels. CRT-SM and CRT-LB levels were highly positively correlated with dmft, dmfs, CSI and their increases over the two years. Levels of infection with oral SM and LB were found to be independent risk factors for primary dental caries, respectively. For an SM concentration in saliva of ≥10⁴ CFU/mL and an LB concentration of <10⁴ CFU/mL, the risk of caries increased by approximately 2.8-fold. When the concentration of LB in saliva was ≥10⁴ CFU/mL and that of SM <10⁴ CFU/mL, the risk of caries increased by approximately 3.9-fold. When the concentration of both SM and LB was ≥10⁴ CFU/mL, the risk increased by approximately 10.9-fold.

Conclusions

Significant positive correlations were found between the level of infection with oral SM and LB and existing oral decay status and the trend in the development of primary dental caries. Infection with SM and LB significantly increased the risk of caries in primary teeth. The CRT^® bacteria is a simple, convenient, reliable, and effective Caries Risk Test.

Differentially Expressed Salivary Proteins in Dental Caries Patients

Dental caries is a multifactorial disease mainly caused by cariogenic bacteria commonly found in the oral cavity. Dental caries may cause demineralization of the tooth, cavitation, hypersensitivity, pulp inflammation, and even tooth loss if left untreated. Saliva secreted in the oral cavity can serve as a tool for identification of biomarkers for early detection of diseases. In the present study, differential expression of salivary proteins from 33 dental caries patients was compared with 10 control subjects. The unstimulated saliva was analyzed by 12% SDS-PAGE and two-dimensional gel electrophoresis. Gelatin and casein zymography was performed to check for protease activity. Also, salivary IgAs from both groups were compared by sandwich ELISA technique. Dental caries patient's saliva showed decreased caseinolytic and increased gelatinolytic activity probably due to metalloproteases and cathepsins. Mean salivary levels of sIgA were also significantly higher (p < 0.018) in dental caries saliva samples. The 2D electrophoresis profile of both the groups showed regions on gel with visually detectable alterations in protein expression. The present study is among the few initial studies in the locality for identification of protein differences in saliva from dental caries patients and has demonstrated a good potential to identify alterations. However, a large population-based analysis is required to validate these findings to be translated as a tool for indicative applications.

Estimation of salivary proteins in early childhood caries before and after treatment using gel electrophoresis

BACKGROUND

Saliva being an important biological fluid of our body contains both specific and nonspecific protective factors which form an integral part of our immune system. Salivary proteins play a substantial role in protecting humans against infection. Their level in oral cavity is subject to constant variations which is dependent on various factors.

PURPOSE

The purpose of the study was to compare the levels of salivary proline-rich proteins (PRPs), glycoproteins, amylase bands, and salivary pH in children with early childhood caries before and after treatment using gel electrophoresis.

MATERIALS AND METHODS

The whole salivary pH, mean protein concentrations, and electrophoretic profiles of the salivary proteins were measured using sodium dodecylsulfate-polyacrylamide gel electrophoresis in both pre- and posttreatment groups. Statistical analysis was done using Statistical Package for Social Sciences (SPSS) version 15.0 software. Chi-square test and independent t-test were used to further compare the results.

RESULTS

The results were statistically significant in all the groups. There was variation in pre- and posttreatment values seen.

CONCLUSION

Salivary proteins (glycoproteins, PRPs, and amylase) establish an imperative defense mechanism as antimicrobial agents.

Metaproteomics associated with severe early childhood caries highlights the differences in salivary proteins

OBJECTIVE

To investigate the salivary metaproteomic characteristics of the children with and without severe early childhood caries (S-ECC).

DESIGN

In this study, we collected unstimulated saliva samples from 34 children (age 3-4 years) with caries free (NC, dmfs (= index of decayed, missing due to caries, or filled tooth surfaces) = 0, n = 23) and with S-ECC (dmfs≥10, n = 11). Salivary proteins were extracted and reduced, and then a Liquid Chromatography/Mass Spectrometry system was used to identify proteins.

RESULTS

Nearly 3000 proteins were identified in this study, and about 3.5 % of the proteins originated from human while 86 % were derived from microbes. The salivary protein types in the NC group were statistically greater than those in the S-ECC group (P <0.05). Specifically, the salivary protein types derived from microbes in the NC group were significantly greater than those in the S-ECC group. Three proteins, human lactoferrin, penicillin-binding protein 1C [Burkholderia ubonensis], human alpha-defensin 1 (F28a mutant), were decreased statistically in the NC group compared to the S-ECC group (P < 0.05). Only one protein, 50S ribosomal protein L17 secreted by Haemophilus haemolyticus, was significantly increased in the NC group compared to the S-ECC group. Salivary IgA was the top highest protein in the NC group whereas human lysozyme was the top highest protein in the S-ECC group.

CONCLUSIONS

The differential proteins recognized in this study may be conducive for finding a caries biomarker. Understanding the metaproteomic characteristics can help us to control the caries from human origin and microbial origin.

Intelligent pH-responsive dental sealants to prevent long-term microleakage

OBJECTIVES

Microleakage is a determinant factor of failures in sealant application. In this study, DMAEM (dodecylmethylaminoethyl methacrylate), a pH-responsive antibacterial agent, was incorporated into resin-based sealant for the first time. The objectives of this study were to: (1) investigate the long-term performance of DMAEM-modified sealants against oral microbial-aging; and (2) investigate the long-term preventive effect of DMAEM-modified sealants on microleakage.

METHODS

Depth-of-cure and cytotoxicity of DMAEM-modified sealants were measured. Then, an aging model using biofilm derived from the saliva of high caries experience children was conducted. After aging, microhardness and surface roughness were measured. Biofilm activity, lactic acid production and exopolysaccharide (EPS) production were measured. 16S rRNA gene sequencing were also performed. The effects of DMAEM on microleakage were tested using an in vitro microleakage assessment.

RESULTS

The addition of DMAEM with a mass fraction of 2.5-10% did not affect depth-of-cure values and cytotoxicity of sealants. Adding 2.5-10% DMAEM did not affect the surface roughness and microhardness after aging. Compared to control, adding 2.5-10% DMAEM reduced biofilm metabolic activity by more than 80%. The lactic acid production and EPS production were reduced by 50% in DMAEM groups. DMAEM-modified sealants maintained the microbial diversity of biofilm after aging, they also inhibited the growth of lactobacillus. The 5% and 10% DMAEM groups exhibited a significant reduction in microleakage compared to control.

SIGNIFICANCE

The long-term antibacterial activities against oral microbial-aging and the long-term microecosystem-regulating capabilities enabled DMAEM-modified sealant to prevent microleakage in sealant application and thus prevent dental caries.

Evaluation of possible biomarkers for caries risk in children 6 to 12 years of age

Background: Electrolytes, proteins, and other salivary molecules play an important role in tooth integrity and can serve as biomarkers associated with caries. Objective: To determine the concentration of potential biomarkers in children without caries (CF) and children with caries (CA). Methods: Unstimulated saliva was collected, and the biomarkers quantified in duplicate, using commercial Enzyme Linked Immunosorbent Assay (ELISA) kits to determine IgA, fibronectin, cathelicidin LL-37, and statherin levels, as well as colorimetric tests to detect formate and phosphate. Results: Significantly higher concentrations of statherin was detected in the CF group (Median: 94,734.6; IQR: 92,934.6-95,113.7) compared to the CA2 group (90,875.0; IQR: 83,580.2-94,633.4) (p = 0.03). Slightly higher median IgA (48,250.0; IQR: 31,461.9-67,418.8) and LL-37 levels (56.1; IQR 43.6-116.2) and a lower concentration of formate were detected in the CF group (0.02; IQR 0.0034-0.15) compared to the group with caries (IgA: 37,776.42; IQR: 33,383.9-44,128.5; LL-37: 46.3; IQR: 40.1011-67.7; formate: 0.10; IQR: 0.01-0.18), but these differences were not statistically significant. Conclusion: The fact that these compounds have been identified as good markers for caries among European adults highlights the difficulty of identifying universal biomarkers that are applicable to all ages or to different populations.

An exploratory study demonstrating that salivary cytokine profiles are altered in children with small area thermal injury

Serum can be used to investigate changes in cytokine concentration following burn injury in children, however for children receiving treatment in an outpatient setting, blood is not routinely collected and therefore cannot be used for monitoring. The aim of this study was to investigate the use of saliva as a non-invasive tool for predicting burn outcomes by measuring the concentration of salivary cytokines in children with small area burns. A multiplex cytokine assay was used to measure 17 cytokines in the saliva of paediatric patients with burns (n = 20) and healthy controls (n = 20). After the removal of cytokines that had >30% of samples below the assay lower detection limit, six cytokines including IL-1β, IL-4, IL-7, IL-8, MCP-1 and TNFα were analysed for association with burns. IL-1β and IL-4 were found to be significantly elevated in the paediatric burn patients compared to healthy controls. Interestingly, IL-1β was also significantly elevated in scald burns, compared to contact burns. In addition, biologically meaningful differences in cytokine concentration were identified in patients with different burn characteristics, which warrant further investigation. This exploratory study provides evidence that cytokines can be detected in the saliva of children and that salivary cytokine profiles differ between healthy controls and children with burns. Overall, this study demonstrates the value of saliva for the investigation of cytokines and its potential application in paediatric diagnostics, specifically in situations where blood collection is not appropriate.

Geographic Variation Did Not Affect the Predictive Power of Salivary Microbiota for Caries in Children With Mixed Dentition

Dental caries is one of the most prevalent chronic oral diseases, affecting approximately half of children worldwide. The microbial composition of dental caries may depend on age, oral health, diet, and geography, yet the effect of geography on these microbiomes is largely underexplored. Here, we profiled and compared saliva microbiota from 130 individuals aged 6 to 8 years old, representing both healthy children (H group) and children with caries-affected (C group) from two geographical regions of China: a northern city (Qingdao group) and a southern city (Guangzhou group). First, the saliva microbiota exhibited profound differences in diversity and composition between the C and H groups. The caries microbiota featured a lower alpha diversity and more variable community structure than the healthy microbiota. Furthermore, the relative abundance of several genera (e.g., Lactobacillus, Gemella, Cryptobacterium and Mitsuokella) was significantly higher in the C group than in the H group (p<0.05). Next, geography dominated over disease status in shaping salivary microbiota, and a wide array of salivary bacteria was highly predictive of the individuals’ city of origin. Finally, we built a universal diagnostic model based on 14 bacterial species, which can diagnose caries with 87% (AUC=86.00%) and 85% (AUC=91.02%) accuracy within each city and 83% accuracy across cities (AUC=92.17%). Although the detection rate of Streptococcus mutans in populations is not very high, it could be regarded as a single biomarker to diagnose caries with decent accuracy. These findings demonstrated that despite the large effect size of geography, a universal model based on salivary microbiota has the potential to diagnose caries across the Chinese child population.

Molecular Screening and Analysis Reveal Novel Oral Site-Specific Locations for the Cariogenic Pathogen Scardovia wiggsiae

Introduction: Scardovia wiggsiae (SW) is a newly identified cariogenic pathogen associated with severe early childhood caries and oral disease. New studies have confirmed the presence of this organism among clinical samples from both pediatric and adult patients. However, the recent discovery of this organism has left researchers with only limited information available regarding the prevalence of this organism—and virtually no information regarding oral site-specific locations. Based upon this lack of information, the overall objective of this study was to perform an oral site-specific analysis of SW prevalence from clinical samples. Methods: Using an approved human subjects protocol, samples (n = 60) from an existing saliva and site-specific biorepository were identified and screened for SW presence using quantitative polymerase chain reaction (qPCR). These data were summarized and subsequently analyzed for correlations with demographic (age, sex, race or ethnicity) or clinical (body mass index or BMI, primary/mixed/permanent dentition, orthodontic brackets) variables. Results: These data revealed that average DNA concentrations from all sample sites (saliva, dorsum of tongue, gingival crevicular fluid (GCF), biofilm of upper buccal molar, and biofilm of lower lingual incisor) ranged between 13.74 and 14.69 μg/μL, with an overall average of 14.30 μg/μL ± 1.12 (standard error or SE). qPCR screening revealed a total of n = 34/60 or 56.7% of patient samples harboring SW. A total of n = 71/170 specific oral sites harbored this organism, with the majority of the SW-positive participant samples harboring SW at more than one oral site, n = 22/34 or 64.7%, including non-traditional sites such as GCF and the dorsum of the tongue. Weak correlations were found between specific SW outcomes in GCF and type of dentition (permanent; R = 0.2444), as well as SW outcomes in saliva with age (R = 0.228) and presence of orthodontic brackets (R = 0.2118). Conclusions: This study may be among the first to provide oral site-specific analysis to reveal the prevalence and location of Scardovia among clinical patient samples. Moreover, these data also provide some of the first evidence to suggest this organism may be present not only in traditional supragingival tooth-associated biofilm sites, but also in non-traditional oral sites including the dorsum of the tongue and the gingival crevice. Based upon these results, these data may represent a significant advance in our understanding of the potential sites and locations that harbor this organism and may help contribute to our understanding of the prevalence, distribution and potential for the development of oral disease among clinic patients.

Cariogenic Biofilm: Pathology-Related Phenotypes and Targeted Therapy

The initiation and development of cariogenic (that is, caries-related) biofilms are the result of the disruption of homeostasis in the oral microenvironment. There is a daily accumulation of dental biofilm on the surface of teeth and its matrix of extracellular polymers supports the host in its defense against invading microbes, thus helping to achieve oral microbial homeostasis. However, the homeostasis can be broken down under certain circumstances such as during long-term exposure to a low pH environment which results in the dominance of acidogenic and acid-tolerating species in the dental biofilm and, thus, triggers the shift of harmless biofilm to an acidic one. This work aims to explore microbial diversity and the quorum sensing of dental biofilm and their important contributions to oral health and disease. The complex and multispecies ecosystems of the cariogenic biofilm pose significant challenges for the modulation of the oral microenvironment. Promising treatment strategies are those that target cariogenic niches with high specificity without disrupting the balance of the surrounding oral microbiota. Here, we summarized the recent advances in modulating cariogenic biofilm and/or controlling its pathogenic traits.

A Review of the Role of Probiotic Supplementation in Dental Caries

Dental diseases are among the common health issues experienced around the world. Dental caries is one of the most predominant oral diseases worldwide. Major factors associated with caries development include poor oral hygiene, the content of specific carbohydrates in the diet, dental biofilm formation, the cariogenic microbial load, reduction in salivary flow, insufficient fluoride exposure, gingival recession, genetic factors, and lack of personal attention to one's dental health. Several preventive measures have been implemented to reduce the risk of the development of caries. Probiotics are live microbes that when administered in suitable amounts confer health benefits on the host; they are recognized as potential adjunct therapeutic agents for several diseases. The present manuscript summarizes recent findings on the role of probiotics in dental caries prevention and the possible mechanisms of probiotic effects. Review of the literature indicates the regular consumption of probiotic products significantly reduced the risk of caries by inhibiting cariogenic bacteria and enriching commensal microbes in the oral cavity. Buffering the salivary pH, production of bacteriocin and enzymes (dextranase, mutanase, and urease), the capacity of competing for the adhesion and colonization on tooth surfaces are the possible mechanisms behind the beneficial effect of probiotics. Further studies are necessary to address the efficacy of long-term probiotic supplementation on the control of dental diseases and the influence of childhood probiotic supplementation on the risk of caries development.

Salivary biochemical indices related to early childhood caries

OBJECTIVES

This study aimed to compare the salivary biochemical indices between caries-free individuals and those with early childhood caries (ECC), and construct a saliva-based caries diagnostic model by analyzing the correlation between salivary biochemical indices and caries severity.

METHODS

A total of 120 children aged 4-6 years were selected and divided into two groups: individuals with ECC (C group, n=60) and healthy children (H group, n=60). Salivary samples were collected to compare the pH, total protein, and ion concentrations between the two groups. The correlation between the salivary biochemical indices and caries severity was examined, and an ECC diagnostic model was established.

RESULTS

The NO₃^- concentration significantly decreased in the C group, whereas the Cl^-, Br^-, NH₄⁺, and Mg²⁺ concentrations significantly increased in the C group (P<0.05). In addition, the salivary caries severity had a significantly negative correlation with the NO₃^- concentration but had a positive correlation with Br^-, Cl^-, and NH₄⁺ concentrations (P<0.05). The ECC diagnostic model based on salivary biochemical indices could yield satisfactory results in terms of distinguishing the C and H groups with over 85% accuracy.

CONCLUSIONS

Salivary biochemical indices can contribute to the diagnosis and risk assessment of ECC.

Use of the Er:YAG Laser in Conservative Dentistry: Evaluation of the Microbial Population in Carious Lesions

The aim of this study is to investigate the Erbium:Yttrio-Aluminum-Granate (Er:YAG) laser photothermal and mechanical effects on cariogenic species concentration and on the microbial load composition of therapeutic cavities, in order to evaluate the possible micro-organisms reduction and make a comparison with manual and rotating conventional therapy (CT). A clinical trial was designed, including adults with active deep carious lesions on permanent teeth who were divided into two groups, i.e., control group and intervention group treated with CT and Er:YAG therapy, respectively. Before and after any conservative treatment, two oral samples were collected using a small sterile microbrush scrubbed within the base of the dentinal cavity tissue. The percentage of reduction and the colony-forming units (CFUs) count after Er:YAG and conventional treatments were compared for total microorganisms, including Candida spp., Streptococcus spp., and Lactobacillus spp. The microbial reduction varied from 90.2% to 100% and was significantly observed for total microorganisms and Streptococcus spp. (p < 0.05). The Er:YAG laser shows the potential for clinical applications, especially with paediatric and complicated patients, thanks to its minimally invasive properties and its effect on the reduction of microbial load.

The Impact of Sport Training on Oral Health in Athletes

Athletes' oral health appears to be poor in numerous sport activities and different diseases can limit athletic skills, both during training and during competitions. Sport activities can be considered a risk factor, among athletes from different sports, for the onset of oral diseases, such as caries with an incidence between 15% and 70%, dental trauma 14-70%, dental erosion 36%, pericoronitis 5-39% and periodontal disease up to 15%. The numerous diseases are related to the variations that involve the ecological factors of the oral cavity such as salivary pH, flow rate, buffering capability, total bacterial count, cariogenic bacterial load and values of secretory Immunoglobulin A. The decrease in the production of S-IgA and the association with an important intraoral growth of pathogenic bacteria leads us to consider the training an "open window" for exposure to oral cavity diseases. Sports dentistry focuses attention on the prevention and treatment of oral pathologies and injuries. Oral health promotion strategies are needed in the sports environment. To prevent the onset of oral diseases, the sports dentist can recommend the use of a custom-made mouthguard, an oral device with a triple function that improves the health and performance of athletes. During training, the sports dentist must monitor the athletes and the sports examination protocol must be implemented with the inclusion of the clinical examination, quantitative and qualitative analysis of saliva and instructions on the use, cleansing and storage of the mouthguard.

Carbonic anhydrase VI activity in saliva and biofilm can predict early childhood caries: A preliminary study

AIM

This study aimed to investigate whether carbonic anhydrase VI activity (CA VI_ACT ), pH, and buffering capacity (BC) in saliva and biofilm could predict the number of lesion occurrence and early childhood caries (ECC).

DESIGN

A cross-sectional study was performed in a sample of 44 children aged 4 to 5 years who were examined regarding their caries status (dmfs + active white spot lesions-WSL) and allocated into two groups: ECC and caries-free (CF). Saliva and biofilm were collected to determine pH, BC, and CA VI_ACT . Data were analyzed using the Student t test, and multiple linear regression and logistic regression analyses followed by the ROC curve.

RESULTS

Children with ECC exhibited lower pH and BC in saliva and a higher CA VI_ACT in both saliva and biofilm. Only saliva pH could predict the dmfs + active WSL. In biofilm, if CA VI_ACT is increased by one pixel/µg, 0.85 ± 0.28 increase is expected in the number of active WSL. Salivary pH and CA VI_ACT in saliva and biofilm had the power to predict ECC occurrence.

CONCLUSION

Changes in saliva pH and CA VI_ACT in biofilm predicted the number of lesion occurrence. Furthermore, CA VI_ACT in both saliva and biofilm can predict propensity for ECC.