Mucin levels in saliva of adolescents with dental caries

Salivary Diagnosis of Dental Caries: A Systematic Review

The activity of dental caries, combined with its multifactorial etiology, alters salivary molecule composition. The present systematic review was developed to answer the following question: "Are salivary biomarkers reliable for diagnosis of dental caries?". Following the "Preferred Reporting Item for Systematic Reviews and Meta-analysis" (PRISMA) guidelines, the review was conducted using multiple database research (Medline, Web of Science, and Scopus). Studies performed on healthy subjects with and without dental caries and providing detailed information concerning the clinical diagnosis of caries (Decayed, Missing, Filled Teeth-DMFT and International Caries Detection and Assessment System-ICDAS criteria) were included. The quality assessment was performed following a modified version of the Joanna Briggs Institute Prevalence Critical Appraisal Checklist. The protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO, ID: CRD42022304505). Sixteen papers were included in the review. All studies reported statistically significant differences in the concentration of salivary molecules between subjects with and without caries (p < 0.05). Proteins were the most investigated molecules, in particular alpha-amylase and mucins. Some studies present a risk of bias, such as identifying confounding factors and clearly defining the source population. Nevertheless, the 16 papers were judged to be of moderate to high quality. There is evidence that some salivary compounds studied in this review could play an important diagnostic role for dental caries, such as salivary mucins, glycoproteins (sCD14), interleukins (IL-2RA, 4,-13), urease, carbonic anhydrase VI, and urea.

Changes in the Composition of Unstimulated and Stimulated Saliva Due to Chewing Sour Cherry Gum and a Toothbrush Change

BACKGROUND

Our previous studies demonstrated that sour cherry anthocyanins (AC) reduce the salivary count of Streptococcus mutans and inhibit salivary amylase activity within 30 minutes after chewing AC gum. AC gum and changing toothbrushes after scaling reduced the Gram-negative species in the unstimulated salivary microbiota. The present study examined the effect of AC gums on salivary factors, including changes in microbiome.

METHODS

The study was conducted over three weeks with two groups; young adults (18-30) and adults (30-45). Ten participants changed their toothbrushes, while the other 10 participants did not change after the control period. After scaling, all participants received three doses of AC gum daily. The salivary mRNA and protein levels of cytokines, mucins, melatonin, and the microbiota of unstimulated and stimulated saliva were determined by polymerase chain reaction, enzyme-linked immunosorbent assay, and 16S rRNA gene sequencing.

RESULTS

Significantly higher levels of tumor necrosis factor α (TNFα), interleukin-1β (IL-1β), mucin5B (MUC5B), mucin7 (MUC7), and melatonin were detected in stimulated saliva. Correlation analysis of these factors with the microbiota showed positive correlations with the genera Lachnospiraceae, Eikenella, Saccharibacteria_(TM7), Streptococcus, Prevotella, and Haemophilus.

CONCLUSIONS

AC chewing gum has a beneficial effect on the composition of the oral microbiome, and toothbrush replacement leads to changes in the levels of salivary pro-inflammatory cytokines.

Exploring the Correlation between Salivary Spinnbarkeit and Caries Scores

INTRODUCTION

In this study, the relationship between the spinnbarkeit, i.e., the stretchability of saliva, and dental caries was investigated.

METHODS

Dentistry students were divided into a group with more than 2 decayed, missed, and filled teeth (DMFT ≥2, n = 30) and caries-free group (DMFT = 0, n = 36).

RESULTS

Unstimulated saliva flow rate, pH, and spinnbarkeit were determined. Salivary spinnbarkeit was significantly lower in the caries-prone group compared to the caries-free group (5.4 ± 3.9 mm vs. 13.5 ± 7.6 mm, respectively, p < 0.001).

CONCLUSION

This suggests that saliva with high spinnbarkeit protects better against dental caries.

Role of Salivary Biomarkers in Diagnosis and Detection of Dental Caries: A Systematic Review

Saliva plays a significant role in oral health and tooth integrity. Salivary components reduce tooth surface exposure to demineralization, protect against teeth wear and aid in enamel remineralization. There is a growing attempt to use salivary markers in diagnosing or predicting caries. However, despite the current information, there has yet to be an agreement among scholars. This study seeks to contribute more evidence on the suitability of salivary biomarkers in dental caries diagnosis. Eligible studies were electronically searched on online databases PubMed, Elsevier's Scopus, EMBASE and Web of Science, and all the studies that met the inclusion criteria were considered. The PECOS criteria guided the study selection process based on the study question. The risk of bias was assessed using the STROBE checklist. Eighteen articles were included in the analysis. All the studies presented relevant data concerning the study objectives. There was evidence of associations between salivary biomarkers and dental caries, and the correlations were either positive or negative. The studies presented significant heterogeneity; thus, a meta-analysis was not possible. Salivary biomarkers appeared to perform crucial and complementary functions toward tooth integrity and thus may be reliable in predicting or diagnosing dental caries in patients.

Caries Management-The Role of Surface Interactions in De- and Remineralization-Processes

BACKGROUND

Bioadhesion and surface interactions on enamel are of essential relevance for initiation, progression and prevention of caries and erosions. Salivary proteins on and within initial carious and erosive lesions can facilitate or aggravate de- and remineralization. This applies for the pellicle layer, the subsurface pellicle and for proteins within initial carious lesions. Little is known about these proteinaceous structures related to initial caries and erosion. Accordingly, there is a considerable demand for an understanding of the underlying processes occurring at the interface between the tooth surface and the oral cavity in order to develop novel agents that limit and modulate caries and erosion. Objectives and findings: The present paper depicts the current knowledge of the processes occurring at the interface of the tooth surface and the oral fluids. Proteinaceous layers on dental hard tissues can prevent or aggravate demineralization processes, whereas proteins within initial erosive or carious lesions might hinder remineralization considerably and restrict the entry of ions into lesions.

CONCLUSIONS

Despite the fact that organic-inorganic surface interactions are of essential relevance for de- and remineralization processes at the tooth surface, there is limited knowledge on these clinically relevant phenomena. Accordingly, intensive research is necessary to develop new approaches in preventive dentistry.

Effects of Carbonated Beverage Consumption on Oral pH and Bacterial Proliferation in Adolescents: A Randomized Crossover Clinical Trial

Sugary soft drinks modify salivary pH and favor bacterial proliferation and are associated with the development of caries. Information on the effects of consuming carbonated drinks without sucrose is limited. Methods: In this crossover clinical trial, salivary and dental biofilm pH were determined at 0, 5, 10, 15, 30, 45, and 60 min after the participants (n = 18) ingested a soft drink with sucrose, a soft drink with aspartame/acesulfame K, carbonated water, and plain water on different days. Dental biofilm cultures were conducted at 0- and 120-min. Results: Salivary pH decreased significantly after ingestion of the sucrose-containing soft drink when compared with the other types of beverages (median difference, -0.3--0.4, p ≤ 0.05), and the greatest difference was found with mineral water. A greater bacterial proliferation (Colony Forming Units [CFU]) was observed after ingestion of the drink with sucrose (↑310 × 103 CFU, p ≤ 0.01), followed by the drink with aspartame/acesulfame K (↑160 × 103 CFU, p ≤ 0.01) and carbonated water (↑60 × 103 CFU, p ≤ 0.05). No significant changes in bacterial proliferation were observed after the consumption of natural water. Conclusions: Ingestion of sucrose-containing soft drinks favors the acidification of salivary pH and the bacterial proliferation of dental biofilm. Although to a lesser extent, soft drinks containing aspartame/acesulfame K also favor bacterial proliferation.

Mucosal Environment Induces Phage Susceptibility in Streptococcus mutans

Pathogenic bacteria are attracted toward mucosa, as it is their way of entry into the body. However, we know surprisingly little about the phage-bacterium interactions in the mucosal environment. Here, we explored the effect of the mucosal environment on growth characteristics and phage-bacterium interactions in Streptococcus mutans, a causative agent of dental caries. We found that although mucin supplementation increased bacterial growth and survival, it decreased S. mutans biofilm formation. More importantly, the presence of mucin had a significant effect on S. mutans phage susceptibility. In two experiments done in Brain Heart Infusion Broth, phage M102 replication was detected only with 0.2% mucin supplementation. In 0.1 × Tryptic Soy Broth, 0.5% mucin supplementation led to a 4-log increase in phage titers compared with the control. These results suggest that the mucosal environment can have a major role in the growth, phage sensitivity, and phage resistance of S. mutans, and underline the importance of understanding the effect of mucosal environment on phage-bacterium interactions.

Mucin Transiently Sustains Coronavirus Infectivity through Heterogenous Changes in Phase Morphology of Evaporating Aerosol

Respiratory pathogens can be spread though the transmission of aerosolised expiratory secretions in the form of droplets or particulates. Understanding the fundamental aerosol parameters that govern how such pathogens survive whilst airborne is essential to understanding and developing methods of restricting their dissemination. Pathogen viability measurements made using Controlled Electrodynamic Levitation and Extraction of Bioaerosol onto Substrate (CELEBS) in tandem with a comparative kinetics electrodynamic balance (CKEDB) measurements allow for a direct comparison between viral viability and evaporation kinetics of the aerosol with a time resolution of seconds. Here, we report the airborne survival of mouse hepatitis virus (MHV) and determine a comparable loss of infectivity in the aerosol phase to our previous observations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Through the addition of clinically relevant concentrations of mucin to the bioaerosol, there is a transient mitigation of the loss of viral infectivity at 40% RH. Increased concentrations of mucin promoted heterogenous phase change during aerosol evaporation, characterised as the formation of inclusions within the host droplet. This research demonstrates the role of mucus in the aerosol phase and its influence on short-term airborne viral stability.

Label-free quantitation of the changes in salivary proteome associated with the chronic consumption of the betel nut (Areca catechu)

Areca nut or betel nut chewing is most frequently used in Pakistan and is associated with a high risk for oral cancer. Until now, however, there has not been any research conducted on the long-term effect(s) of betel nut chewing on the saliva proteome. In the present study, initially, the changes in the saliva proteome associated with betel nut chewing were investigated. Secondly, the analysis was focused on the changes in salivary proteome with respect to prolonged usage of betel nuts. After extraction, the saliva proteins were digested into peptides and these were subsequently analyzed using mass spectrometry. Data are available via ProteomeXchange with identifier PXD029768. Label-free quantitation of saliva samples revealed a total of 12 proteins that were differentially expressed between betel nut addicts (BNAs), and the control group. The study groups were further divided into three subgroups, the BNA-1, BNA-2, and BNA-3 groups, with respect to the extent of consumption of betel nuts in terms of years. The data analysis revealed a more detailed profiling of proteins expressed after five, ten, and more than ten years of betel nut consumption. A total of 30, 17, and 22 proteins were found to be differentially expressed when divided into the BNA-1, BNA-2, and BNA-3 groups. The present study shows that the chronic usage of betel nuts leads to the expression of proteins, such as SPARC1, profilin, and SBSN, which are known to be involved in head and neck cancers.

Mucins 5b and 7 and secretory IgA in the oral acquired pellicle of children with caries and caries-free children

OBJECTIVE

The objective of this study was to determine whether differences in the abundance of mucins 5b and 7 as well as secretory IgA exist in the oral acquired pellicle between children with active caries and caries-free children.

DESIGN

Pellicle formation was performed for 10 min in-situ on ceramic slabs in the oral cavity of children (5-7 years of age) with caries (n = 15) and without signs of caries (n = 13). Furthermore, unstimulated saliva was collected. Concentrations of Muc5b, Muc7 and sIgA were measured in desorbed pellicle eluates and in saliva.

RESULTS

Significantly larger concentrations of Muc5b, Muc7 and sIgA were detected in the pellicle obtained from children with caries compared to caries-free children. However, in the salivary samples concentrations of mucins Muc5b and Muc7 as well as sIgA did not differ significantly between the two groups.

CONCLUSIONS

All three pellicle components Muc5b, Muc7 as well as sIgA could be identified as potential biomarkers for early childhood caries with high sensitivity and specificity. This could contribute to a better understanding of the different caries susceptibility in children.

Evaluation of salivary thiobarbituric acid reactive substances, total protein, and pH in children with various degrees of early childhood caries: a case-control study

PURPOSE

According to new studies, oxidative stress may play an important role in the beginning and progression of oral diseases. The aim of this study was the evaluation of thiobarbituric acid reactive substances (TBARS) as an indicator of lipid peroxidation, total protein, and pH of saliva in children with various degrees of early childhood caries in comparison with caries-free children.

METHODS

This case-control study was carried out on 90 children 3-5 years old in three equal groups, including caries-free children (CF), early childhood caries (ECC), and severe early childhood caries (S-ECC) who were age- and sex matched. Saliva pH was measured using a paper pH meter and TBARS and total protein were measured by spectrophotometer methods and data were statistically analysed.

RESULTS

TBARS and total protein levels in ECC and S-ECC groups were significantly higher than the CF group (p < 0.001), but pH was not significantly different between groups. There were no significant differences between ECC and S-ECC groups in any of the studied indicators.

CONCLUSION

Considering the limitations of the present study, the results showing the higher salivary TBARS levels in the S-ECC and ECC groups compared to caries-free children, lead to the conclusion that oxidative stress could be considered as a risk factor for early childhood caries.

The Use of Saliva as a Biosample in the Light of COVID-19

Saliva is easy to collect and a biofluid that is readily available without the need for special equipment for its collection. The collection process, which is non-invasive and inexpensive, leads to obtaining a biomaterial that can serve as a source of information for molecular diagnostics of diseases in general medicine, genetics and dentistry. Unfortunately, many of the salivary methodologies are lacking important parameters to provide for not only the safety of the operator, but also the quality and reproducibility of the research. Since the COVID-19 pandemic, salivary diagnostics demonstrate a great potential for research of SARS-CoV 2. In this review, good practice for unstimulated saliva collection and patient preparation was provided, based on the latest literature and available guidelines. Schemes for saliva collection procedures were presented following an extended literature search. Descriptions of salivary probes/cups, techniques of saliva collection, and the use of specific buffering solutions for the stability of collected samples for SARS-CoV-2 detection were also evaluated.

Clinical anatomy of the inferior labial gland: a narrative review

Objective

In this article we review the literature on the inferior labial gland from a clinical and anatomical perspective.

Background

Regardless of its importance in clinical practice, there are no medical literature that comprehensively reviewed the inferior labial gland.

Methods

A database search using PubMed and Google Scholar was conducted. The following keywords were used in the search: "lower labial salivary gland", "lower labial gland", "inferior labial salivary gland", AND "inferior labial gland".

Conclusions

The human labial glands are types of minor salivary gland that continuously secrete small amounts of mucous and serous substances to maintain oral health. The inferior labial glands are innervated by the inferior labial branch of the mental nerve, and the inferior labial branch of the facial artery is the main arterial supply to the lower lip. Although they only have an auxiliary role in saliva production compared to the major salivary glands, minor salivary glands provide a certain amount of lubrication in the oral cavity by the continuous outflow of saliva. The inferior labial gland not only promotes moisturization in the oral cavity but also secretes substances with antibacterial effects, which is important for the function of the oral cavity. A recent study showed that the rate of salivary secretion from the inferior labial glands does not change with age, and in some cases the inferior labial glands are used for diagnosing intractable diseases such as Sjogren's syndrome and cystic fibrosis. In addition, since the inferior labial glands themselves can be the site of cyst and/or neoplasia development, we should be careful to distinguish them from other diseases. Elucidation of the anatomy, physiology, and pathology of the inferior labial glands, is important for understanding human health and diseases.

Which salivary components can differentiate metabolic obesity?

Background

Obesity is a multifactorial disease and represents a global and relevant health problem. The aim of the study was to assess the concentration of pro-inflammatory cytokines (tumor necrosis factor-α (TNF-α), interleukin-8 (IL-8)) and other selected proteins as well as enzymes (soluble intercellular adhesion molecule 1 (sICAM1), calprotectin, matrix metalloproteinase-9 (MMP-9), matrix metalloproteinase-2 (MMP-2), toll like receptor 2 (TLR2)) detectable in the saliva of women who varied in body composition. It was debated whether there are marker factors in saliva that could indicate metabolic obesity.

Methods and findings

The pilot study included 10 women with obesity (BMI>30 kg/m2) and 6 women with normal body weight (control group). The levels of TNF-α, IL-8, sICAM1, calprotectin, MMP-9, MMP-2, and TLR2 were checked by using the ELISA technique. We proved that women with metabolic obesity had significantly increased concentrations of IL-8, calprotectin, and MMP-2 in comparison with healthy subjects. Significant positive correlations of BMI with TNF-α, IL-8, and MMP-2 were observed. Similarly, the content of fat (in kg and %) in the bodies of the women correlated positively with TNF-α, IL-8, and MMP-2. Whereas, the visceral adipose tissue (VAT) correlated positively only with TNF-α and MMP-2, similarly to VAT/SAT. The WHR (waist hip ratio) was also positively correlated with TNF-α and MMP-2. Interestingly, we found that the level of insulin positively correlated with TNF- α concentration, which additionally confirmed metabolic obesity.

Conclusions

We found that positive correlations of body mass index were observed only with salivary concentrations of TNF-α, MMP-2, and IL-8. Thus, it is worth conducting a study among a larger number of people taking into account these three salivary components.

Saliva as a diagnostic tool for dental caries, periodontal disease and cancer: is there a need for more biomarkers?

Introduction: A biomarker is a biological indicator of normal or pathogenic processes. Identification of biomarkers is useful for the prevention, diagnosis and prognosis of diseases as well as for monitoring the progression of pathological disorders. Several types of molecules present in biological fluids can act as biomarkers such as DNA, coding and non-coding RNA, lipids, metabolites, proteins and even microbes. In this context, saliva emerges as a useful diagnostic tool for the detection of biomarkers involved with oral and systemic diseases, since it reflects the pathophysiological conditions of the organism and allows early, rapid, practical and noninvasive detection of biomarkers.Areas covered: This review discusses the properties of saliva as a diagnostic tool and addresses the main identified biomarkers related to dental caries, periodontal disease, head and neck cancer and other types of cancer of considerable incidence among the world population.Expert commentary: Despite extensive efforts which have been directed toward the identification of one or a combination of biomarkers with good predictive values for the early detection of dental caries, periodontal disease and cancer, these biomarkers still need validation before chairside point-of-care devices can be widely used in the clinic.

Hygiene protocols for the treatment of denture-related stomatitis: local and systemic parameters analysis - a randomized, double-blind trial protocol

Background

Denture-related stomatitis (DS) is chronic multifactorial inflammation, strongly related to the presence of the biofilm that is the complex structure formed by microorganisms held together by a mucus-like matrix of carbohydrate that adheres to different surfaces, including the denture surface. DS has recently been correlated with deleterious cardiovascular alterations. The potential effect of hygiene protocols in the control of DS and randomized clinical trials that address this oral condition with cardiovascular complications are important in clinical decision-making.

Material/design

A clinical trial, randomized, double-blind, and with parallel groups, will be conducted in Brazil The sample will consist of 100 patients without teeth in both arches, users of at least maxillary complete dentures, and diagnosed with DS, who will be allocated to groups (n = 25 per group) according to the different hygiene protocols: (1) brushing of the palate and immersion of the prosthesis in 0.25% sodium hypochlorite solution (positive control); (2) brushing of the palate and immersion of the prosthesis in 0.15% triclosan solution; (3) brushing of the palate and immersion of the prosthesis in lactose monohydrate; or (4) brushing the palate with citric acid and immersing the prosthesis in lactose monohydrate. The response variables will be heart rate variability and alteration of blood pressure (systemic level), remission of DS, removal of biofilm, reduction of microbial load (colony-forming units (CFU)), mouth and prosthesis odor level, expression of MUC1, proinflammatory cytokines, C-reactive protein (CRP), viscosity, pH and salivary flow (locally); patient-centred qualitative analysis will also be undertaken. Measurements will be performed at baseline and 10 days after the interventions. The results obtained will be statistically analyzed as pertinent, with a level of significance of 0.05.

Discussion

This study will provide a guideline for clinical practice regarding the use of hygiene protocols in the treatment of oral diseases (DS) mediated by biofilm. Also, it may provide evidence of correlation of oral manifestation with cardiac risk.

Trial registration

Brazilian Registry of Clinical Trials, RBR-4hhwjb. Registered on 9 November 2018.

Comparative evaluation of salivary malondialdehyde levels as a marker of lipid peroxidation in early childhood caries

Objective

The aim of this study was to evaluate the association between lipid peroxidation and dental caries in children with ECC by estimating the levels of MDA in saliva of children.

Materials and Methods

A total of 150 children were selected; 75 children with ECC and 75 children without caries (non-ECC). Saliva samples were collected and centrifuged at 12,000 rpm for 24 min at 4°C to obtain a supernatant. MDA levels were estimated by Buege and Aust method by using thiobarbituric acid. The data obtained were analyzed by Student's t-test to compare MDA levels between the groups.

Results

MDA levels were higher in children with ECC. There was no statistically significant difference between children with ECC and without ECC (non-ECC).

Conclusion

MDA levels were slightly higher in children with ECC, indicating the role of lipid peroxidation in the carious process.

MUC7 Level As A New Saliva Risk Factor For Dental Caries In Adult Patients

Purpose: Data currently available indicate the significance of salivary mucins MUC5B and MUC7 in the protection of teeth against caries. Our study aimed to determine the relationship between dental caries in adults and levels of MUC5B and MUC7. Methods: The studies were conducted on 45 adult subjects selected on the basis of dental examination and calculation of the DMFT (Decayed, Missing, and Filled Teeth) index. Among these patients, two research groups were distinguished: group 1 included 19 caries-free subjects (DMFT = 0); and group 2 included 26 patients with severe caries (DMFT > 13.9). Samples of whole unstimulated saliva were collected and centrifuged. MUC5B and MUC7 content in saliva supernatant were estimated using an enzyme-linked immunosorbent sandwich assay (ELISA). Analysis of the obtained data receiver operating characteristic (ROC) curves was employed to define relationships between the contents of the studied mucins and the detected dental caries. Results: In subjects from group 1, the mean level of MUC5B amounted to 0.63 ± 0.35 ng/ml and this was significantly higher than the concentration of mucin in patients of group 2, which amounted to 0.38 ± 0.32 ng/ml (p = 0.023). The mean level of MUC7 amounted to 5.47 ± 1.18 ng/ml and this was significantly higher than the level of the mucin in group 2, which was 1.39 ± 0.86 ng/ml (p< 0.0001). In parallel, a relationship was detected between levels of the examined mucins and manifestation of dental caries. For MUC7, the optimal cut-off value was obtained (i.e. corresponding to 100% sensitivity and specificity), amounting to 2.5 ng/ml for the detection of dental caries risk. Conclusions: Development of dental caries is linked to reduced concentrations of MUC5B and MUC7. The level of MUC7 may represent a significant parameter clinically suitable for evaluation of disease risk.

Saliva as a biomarker for dental caries: A systematic review

AIM

The aim of the present review article is to establish a systematic review to describe the role of various salivary components such as pH, buffering capacity, proteins, electrolyte, antioxidant, enzymes, and minerals in occurrence and initiation of dental caries in participants with and without dental caries.

METHODOLOGY

An electronic search was conducted in the PubMed, Scopus, Web of Science, and Google Scholar databases. The MESH terms (Medical Subject Headings) were "dental caries susceptibility," "caries risk assessment, "Salivary Biomarker," "saliva," "Proteins," "electrolytes," "biomarker," "Anti-oxidant's." The database search was limited to the studies published between 2008 and 2018 and only human studies were included. Furthermore, the STROBE criteria checklist was used to analyze the studies which had to be included in the systematic review.

RESULTS

A total of 150 articles were retrieved through electronic database. After evaluating the title, abstract, and full text of these articles, only 11 were selected for the present systematic review. However, two articles were excluded because they were classified as high risk of bias according to the STROBE criteria. Out of 9 studies selected, 5 were classified as low-risk bias and 4 were classified as moderate-risk bias.

CONCLUSION

Based on the results of the systematic review, out of 11 studies, 7 found to have a statistically significant difference between individuals with and without caries experience. Hence, it can be concluded that there is an association between various components of saliva and dental caries.

Human salivary proteins and their peptidomimetics: Values of function, early diagnosis, and therapeutic potential in combating dental caries

Saliva contains a large number of proteins that play various crucial roles to maintain the oral health and tooth integrity. This oral fluid is proposed to be one of the most important host factors, serving as a special medium for monitoring aspects of microorganisms, diet and host susceptibility involved in the caries process. Extensive salivary proteomic and peptidomic studies have resulted in considerable advances in the field of biomarkers discovery for dental caries. These salivary biomarkers may be exploited for the prediction, diagnosis, prognosis and treatment of dental caries, many of which could also provide the potential templates for bioactive peptides used for the biomimetic management of dental caries, rather than repairing caries lesions with artificial materials. A comprehensive understanding of the biological function of salivary proteins as well as their derived biomimetic peptides with promising potential against dental caries has been long awaited. This review overviewed a collection of current literature and addressed the majority of different functions of salivary proteins and peptides with their potential as functional biomarkers for caries risk assessment and clinical prospects for the anti-caries application.

Oral epithelial MUC1 and oral health

OBJECTIVES

To provide information about MUC1, epithelial membrane-bound mucin, in terms of its role in oral health.

DESIGN

The expression and functional roles of MUC1 in the oral mucosa and salivary glands were reviewed. Information on the modulation of oral mucosal epithelial MUC1 expression compared with that of endometrial epithelial MUC1 expression was also reviewed. In addition, the possible associations between oral mucosal epithelial MUC1 and oral diseases were explored.

RESULTS

MUC1 is expressed in the oral mucosa and major and minor salivary glands. Protection of oral mucosal surfaces is believed to be the main function of oral mucosal epithelial MUC1. Its role in the salivary glands is thought to facilitate salivary flow through the ductal system. Information on the role of MUC1 in signal transduction and modulation of immune function in the oral cavity is sparse. However, the possible roles of MUC1 in dry mouth conditions, burning mouth syndrome, dental caries, and oral candidiasis have been suggested.

CONCLUSIONS

Despite limited information, it is clear that oral epithelial MUC1 plays an important role in oral health. Further research evaluating the physiological and pathological roles of MUC1 in the oral cavity is warranted.

Salivary Protein Roles in Oral Health and as Predictors of Caries Risk

This work describes the current state of research on the potential relationship between protein content in human saliva and dental caries, which remains among the most common oral diseases and causes irreversible damage in the oral cavity. An understanding the whole saliva proteome in the oral cavity could serve as a prerequisite to obtaining insight into the etiology of tooth decay at early stages. To date, however, there is no comprehensive evidence showing that salivary proteins could serve as potential indicators for the early diagnosis of the risk factors causing dental caries. Therefore, proteomics indicates the promising direction of future investigations of such factors, including diagnosis and thus prevention in dental therapy.

The impact of MUC5B gene on dental caries

OBJECTIVE

To identify the impact of MUC5B polymorphisms on dental caries.

METHODS

A case-control study was performed with patients recruited at Pontifícia Universidade Católica do Paraná. These individuals were aged 12 years old or more. Dental caries was diagnosed using the International Caries Detection and Assessment System, and the effects of socioeconomic, dietary, and hygiene factors on dental caries were investigated. Furthermore, buccal cells were collected, and their DNA was extracted and amplified using PCR. Uni-, bi-, and multivariate analyses were performed.

RESULTS

Two hundred patients were recruited, 100 were assigned to the case group and 100 to the control group. In the bivariate analysis, the following variables showed significant results: ethnicity (p = .008), biofilm (p < .001), and gingivitis (p < .001). The MUC5B gene affected dental caries with the markers rs2735733 (p < .001), rs2249073 (p < .001), and rs2857476 (p < .001). In the multivariate analysis, the biofilm variable remained significant (p = .026), as did the following markers from the MUC5B gene: rs2735733 (p = .019), rs2249073 (p < .025), and rs2857476 (p < .005).

CONCLUSION

Genetic variations in the MUC5B gene can influence dental caries.

Mucin 5B in saliva and serum of patients with oral lichen planus

Oral lichen planus (OLP) is among the most common oral diseases. Its etiopathogenesis has yet to be clearly identified. OLP patients complain of mouth dryness. This study aimed to assess the level of Mucin 5B in OLP patients with xerostomia. This study was conducted on 30 OLP patients and 30 healthy individuals. In addition to patient complaint of mouth dryness, xerostomia was assessed by tongue blade and lipstick tests. Stimulated and unstimulated saliva were collected in plastic vials by spitting method. Level of Mucin 5B was measured by ELISA. Unstimulated saliva flow was significantly lower in OLP patients (P = 0.0001). Stimulated saliva flow was not significantly different between the two groups (P > 0.05). Level of Mucin 5B in unstimulated saliva was significantly lower in OLP group (P = 0.0001) while it was not significantly different in stimulated saliva of the two groups (P > 0.05). Level of Mucin 5B was significantly higher in serum of OLP patients (P = 0.016). Both saliva flow and level of Mucin 5B decrease in OLP patients. Since Mucin 5B is effective for wetting and lubrication of the oral cavity, this result can suggest a possible reason for mouth dryness in OLP patients.

Detection of inflammatory biomarkers in saliva and urine: Potential in diagnosis, prevention, and treatment for chronic diseases

Inflammation is a part of the complex biological response of inflammatory cells to harmful stimuli, such as pathogens, irritants, or damaged cells. This inflammation has been linked to several chronic diseases including cancer, atherosclerosis, rheumatoid arthritis, and multiple sclerosis. Major biomarkers of inflammation include tumor necrosis factor, interleukins (IL)-1, IL-6, IL-8, chemokines, cyclooxygenase, 5-lipooxygenase, and C-reactive protein, all of which are regulated by the transcription factor nuclear factor-kappaB. Although examining inflammatory biomarkers in blood is a standard practice, its identification in saliva and/or urine is more convenient and non-invasive. In this review, we aim to (1) discuss the detection of these inflammatory biomarkers in urine and saliva; (2) advantages of using salivary and urinary inflammatory biomarkers over blood, while also weighing on the challenges and/or limitations of their use; (3) examine their role(s) in connection with diagnosis, prevention, treatment, and drug development for several chronic diseases with inflammatory consequences, including cancer; and (4) explore the use of innovative salivary and urine based biosensor strategies that may permit the testing of biomarkers quickly, reliably, and cost-effectively, in a decentralized setting.

Salivary mucins in host defense and disease prevention

Mucus forms a protective coating on wet epithelial surfaces throughout the body that houses the microbiota and plays a key role in host defense. Mucins, the primary structural components of mucus that creates its viscoelastic properties, are critical components of the gel layer that protect against invading pathogens. Altered mucin production has been implicated in diseases such as ulcerative colitis, asthma, and cystic fibrosis, which highlights the importance of mucins in maintaining homeostasis. Different types of mucins exist throughout the body in various locations such as the gastrointestinal tract, lungs, and female genital tract, but this review will focus on mucins in the oral cavity. Salivary mucin structure, localization within the oral cavity, and defense mechanisms will be discussed. These concepts will then be applied to present what is known about the protective function of mucins in oral diseases such as HIV/AIDS, oral candidiasis, and dental caries.

The assessment of sIgA, histatin-5, and lactoperoxidase levels in saliva of adolescents with dental caries

BACKGROUND

Saliva contains a number of protective factors such as mucins, immunoglobulins (e.g., IgA, IgG, and IgM), and enzymes (e.g., lysozyme and lactoperoxidases) that play an important role in the maintenance of oral health. The aim of this study was to compare levels of sIgA, histatin-5, and lactoperoxidase in saliva of adolescents with dental caries.

MATERIAL AND METHODS

Thirty-five adolescents (age 18 years) from high school were examined. Eight subjects with DMF=3 (Group I) and 27 adolescents with DMF>11 (Group II) were enrolled for this study. Clinical evaluation procedures comprised oral examination (including tooth, periodontal, and oral mucosal status) and collection of saliva samples. Saliva was collected for enzyme-linked immunosorbent assay (ELISA) and was used for determination of sIgA, histatin-5, and lactoperoxidase levels.

RESULTS

Our results showed that adolescents with very high intensity of dental caries (DMF>11) had increased levels of sIgA, histatin-5, and lactoperoxidase compared to adolescents with lower intensity of caries. The increase was statistically significant (p<0.05).

CONCLUSIONS

We suggest that high intensity of caries is associated with increased levels of some salivary components - sIgA, histatin-5 and lactoperoxidase - that possess strong bactericidal or bacteriostatic effects, resulting in aggregation of oral bacteria and their clearance from the oral cavity.