Comparative Study of Salivary pH, Buffer Capacity, and Flow in Patients with and without Gastroesophageal Reflux Disease

A Review on Optical Biosensors for Monitoring of Uric Acid and Blood Glucose Using Portable POCT Devices: Status, Challenges, and Future Horizons

The growing demand for real-time, non-invasive, and cost-effective health monitoring has driven significant advancements in portable point-of-care testing (POCT) devices. Among these, optical biosensors have emerged as promising tools for the detection of critical biomarkers such as uric acid (UA) and blood glucose. Different optical transduction methods, like fluorescence, surface plasmon resonance (SPR), and colorimetric approaches, are talked about, with a focus on how sensitive, specific, and portable they are. Despite considerable advancements, several challenges persist, including sensor stability, miniaturization, interference effects, and the need for calibration-free operation. This review also explores issues related to cost-effectiveness, data integration, and wireless connectivity for remote monitoring. The review further examines regulatory considerations and commercialization aspects of optical biosensors, addressing the gap between research developments and clinical implementation. Future perspectives emphasize the integration of artificial intelligence (AI) and healthcare for improved diagnostics, alongside the development of wearable and implantable biosensors for continuous monitoring. Innovative optical biosensors have the potential to change the way people manage their health by quickly and accurately measuring uric acid and glucose levels. This is especially true as the need for decentralized healthcare solutions grows. By critically evaluating existing work and exploring the limitations and opportunities in the field, this review will help guide the development of more efficient, accessible, and reliable POCT devices that can improve patient outcomes and quality of life.

A Rapid and Modular Nanobody Assay for Plug-and-Play Antigen Detection

Rapid and portable antigen detection is essential for managing infectious diseases and responding to toxic exposures, yet current methods face significant limitations. Highly sensitive platforms like the Enzyme-Linked Immunosorbent Assay (ELISA) are time- and cost-prohibitive for point-of-need detection, while portable options like lateral flow assays (LFAs) require systemic overhauls for new targets. Furthermore, the complex infrastructure, high production costs, and extended timelines for assay development constrain manufacturing of traditional diagnostic platforms in low-resource settings. To address these challenges, we describe the Rapid and Modular Nanobody Assay (RAMONA) as a versatile antigen detection platform that leverages nanobody-coiled coil fusion proteins for modular integration with downstream readout methods. RAMONA merges the portability of LFAs with the benefits of nanobodies, such as their smaller size, improved solubility, and compatibility with cell-free protein synthesis systems, enabling on-demand biomanufacturing and rapid adaptation for diverse targets. We demonstrate assay generalizability through the detection of three distinct protein targets, robustness across various temperatures and incubation periods, and compatibility with saliva samples and cell-free synthesis. Detection occurs in under 30 minutes, with results strongly and positively correlating to ELISA data while requiring minimal resources. Moreover, RAMONA supports multiplexed detection of three antigens simultaneously using orthogonal capture probes. By overcoming several limitations of traditional immunoassays, RAMONA represents a significant advancement in rapid, adaptable, and field-deployable antigen detection technologies.

Exploring the potential of mucoadhesive buccal films in geriatric medicine

As the global demographic shifts toward an aging society, the geriatric patient population is steadily increasing. These patients often suffer from comorbidities and require numerous oral medications, which can be especially challenging for dysphagic geriatric patients. Mucoadhesive buccal films (MBFs) seem promising and could reduce pill burden, simplify administration, and enable individualized drug therapy. This review aims to explore the age-related changes in the oral cavity and their impact on MBF delivery, including potential strategies to overcome these age-related barriers to drug delivery. It was observed that aging impacts the oral mucosa as well the properties of the saliva. There are several studies in the application of buccal films including the use of a wide range of permeation enhancers. The 3D printing of buccal films seems to introduce dosing flexibility to buccal film manufacturing.

Fluoride Levels in Saliva After the Application of Fluoride Varnishes in a Preventive Oral Health Program in Pregnant Women: A Randomized Controlled Trial

PURPOSE

Gestation is a time in women's lives when many physiological changes occur that have systemic and oral repercussions, especially in the periodontium. The aim of the study is to determine the oral health status, plaque index, oral health related quality of life, and concentration of fluoride in saliva, after the application of fluorinated varnishes, of pregnant women participating in a preventive oral health program.

MATERIAL AND METHODS

A randomized clinical trial was carried out on pregnant patients involved in an oral health program. Data was collected on socio-demographic aspects, hygiene habits, beliefs, epidemiological indexes such as Decayed, Missing, and Filled Teeth (DMFT); International Caries Detection and Assessment System (ICDAS); Community Periodontal Index (CPI); Caries Management by Risk Assessment (CAMBRA); and the Oral Health Related Quality of Life Index (OHIP-14). Three reviews were carried out during the gestation period (Day 1, 15, and 30). The fluoride varnishes applied in the study were Clinpro White Varnish, Profluorid Varnish, and MI Varnish.

RESULTS

A total of 89 women were evaluated. Most patients were Spanish and married, with a mean age of 34.3. The mean DMFT was 7.2 (± 4.51), the plaque index was 52%, and there was a low risk of caries. A poorer quality of life was linked to an increased risk of caries, high DMFT values, high ICDAS codes, and high plaque index. The concentration of fluoride in saliva immediately after the application with MI Varnish reaches values of fluor concentration 238.51 ± 151.87 much higher than the other varnishes (p < 0.05); however, after 30 days the values were reduced without significant differences for the three study groups Clinpro White Varnish (0.21 ± 0.29), MI Varnish (0.34 ± 0.34) and Profluorid Varnish (0.16 ± 0.07).

CONCLUSION

In general, pregnant women had good oral health, which improved after participating in the program, and good oral quality of life, with a negative influence due to caries lesions and plaque. In all study groups concentration values dropped to baseline 15 and 30 days after the application of fluoride.

The Oral Microbiome and Systemic Health: Bridging the Gap Between Dentistry and Medicine

The oral microbiome, consisting of a mixture of bacteria, fungi, and viruses, is an important contributor to oral and systemic health. Microbial balance disruptions are associated with oral pathologies like dental caries and periodontitis as well as systemic diseases such as cardiovascular diseases, adverse pregnancy outcomes, and respiratory diseases. This review explores the mechanistic pathways linking oral dysbiosis to systemic inflammation, endothelial dysfunction, and immune modulation. The roles of key microbial species in health and disease are analyzed, with an emphasis on how hematogenous dissemination leads to systemic pathologies through inflammatory signaling. Also, advances in high throughput sequencing are discussed, as well as microbial diversity and its implications for diagnostics and therapeutics. The review highlights the potential of oral microbiota-targeted interventions to mitigate systemic diseases through dentistry and medicine integration, by throwing light on interdisciplinary strategies. Future work should focus on the evaluation of the mechanisms by which the oral microbiome plays a role in systemic diseases through the integration of multi-omics approaches such as metagenomics, transcriptomics, and metabolomics. Furthermore, clinical trials need to be designed in a way to evaluate the efficacy of microbiome-targeted therapies in the prevention of cardiovascular diseases, adverse pregnancy outcomes, and autoimmune disorders.

Impact of Demineralization Time on Enamel Microhardness Reduction and Lesion Depth: An In Vitro Study

INTRODUCTION

The duration of acid exposure is a critical factor in determining an individual's risk of developing caries. The objective of this study was to investigate the correlation between demineralization time and two key parameters: microhardness and depth of an enamel caries lesion.

METHODS

Sixty recently extracted human teeth were mounted in acrylic resin and randomly divided into five groups (n = 12). First, 400 grit and then 1,000 grit sandpaper were applied to the buccal surfaces for five minutes each. Other surfaces, except buccal surfaces, were coated with an acid-resistant varnish. The groups were stored in the same demineralization solution (pH 4.35-4.65), respectively, for a duration of 60, 72, 84, 96, and 108 hours. Before and after exposure to acidic solutions, the surface microhardness of samples (SMH) was evaluated using a Vickers pyramid diamond tip with a 100 gram load applied for 15 seconds. Three measurements were taken from each sample surface, and the average sample value was obtained by averaging the measurements. The depth of the lesions in three specimens from each group was evaluated from five different demineralized pits under a stereomicroscope. Data were analyzed by one-way ANOVA and post-hoc Tukey's honestly significant difference (HSD) tests.

RESULTS

After acid exposure, SMH values significantly decreased in all groups (p = 0.001; p < 0.01) Statistically significant differences were shown between all groups in terms of Δhardness (p < 0.05). After 72 hours of demineralization, the microhardness values tend to decrease more as the exposure time increases (p = 0.001; p < 0.01). The mean lesion depths were varied from 4.01 ± 0.71 µm to 13.7 ± 1.17 µm.

CONCLUSION

Our findings show that there is a positive correlation between the duration of demineralization and lesion depth and a negative correlation between the duration of demineralization and microhardness. We assume that initial lesions may deepen quickly, especially after 72 hours.

Salivary Profile Analysis Based on Oral Cancer Risk Habits: An Observational Cross-Sectional Study

BACKGROUND

In Indonesia, cultural practices such as betel quid chewing, smoking, and alcohol consumption are prevalent. These practices are known risk factors for oral cancer and may influence the salivary profile, which is essential for maintaining oral health.

PURPOSE

To compare the salivary profiles of individuals with and without risk factors for oral cancer.

METHODS

The study included 49 individuals identified as having risk factors for oral cancer. Unstimulated saliva samples were collected. Various parameters were measured, including salivary pH, flow rate (FR), thickness, color, turbidity, and the levels of IL-1β and IL-8. Data were analyzed using Chi-square and t-tests.

RESULTS

A significant difference was found in salivary IL-1β levels between the two groups (p = 0.009), with higher levels observed in individuals with oral cancer risk factors. Notably, the salivary IL-1β concentrations showed significant differences between the smoking group (p = 0.021; OR = 2.94) and the alcohol-drinking group (p = 0.007; OR = 4.96) compared to the control group. However, no significant differences were observed between the groups in terms of salivary viscosity, color, turbidity, flow rate, acidity, or IL-8 levels (p > 0.05).

CONCLUSION

Individuals with risk factors for oral cancer exhibit distinct salivary IL-1β profiles compared to those without such risk factors, particularly those who practice alcohol drinking.

The Association Between Dental Caries and Salivary Buffering Capacity in Syrian Patients Diagnosed with Sickle Cell Disease

Background Sickle cell disease (SCD) is a genetic disorder caused by mutations in the HBB gene, resulting in the abnormal shape of red blood cells. This condition is accompanied by various oral manifestations including salivary gland dysfunction leading to a heightened susceptibility to dental caries. This disorder is primarily treated with hydroxyurea. This study aims to assess dental caries utilizing the decay, missing, filling teeth (DMFT) index and evaluate salivary buffering capacity in patients diagnosed with SCD (HbSS type). The study also aims to assess the relationship between DMFT and salivary buffering capacity. Additionally, the study aimed to find a correlation between treatment with hydroxyurea and changes in both dental caries and salivary buffering capacity. Methods This case-control study enrolled a total of 100 participants aged between 20 and 50 years. The participants were divided into two groups: the study group, which comprised 70 individuals diagnosed with SCD (HbSS type), who were asked to report their current use of hydroxyurea, and the control group, which included 30 healthy individuals. Dental caries were assessed using the DMFT index, while salivary buffering capacity was measured using a pH meter model 420A device. Results The study group exhibited a mean DMFT index value of 6.39 compared to 5.20 in the control group. This difference was statistically significant (P-value=0.037), indicating higher DMFT values among patients with SCD. Salivary buffering capacity was significantly lower in the study group compared to the control group, with average values of 6.47 and 6.88, (P-value=.022). Interestingly, the administration of hydroxyurea impacted salivary buffering capacity, resulting in lower values for individuals using the drug (P-value=0.039). Conversely, hydroxyurea did not have a significant effect on DMFT values (P-value=0.317). Conclusion SCD increases susceptibility to dental caries and is associated with significant changes in salivary composition. At the same time, the potential negative impact of hydroxyurea is acknowledged.

Effect of Fixed Orthodontic Appliances on Oral Microbial Changes and Dental Caries Risk in Children: A 6-Month Prospective Study

Introduction

Orthodontic treatment can alter the oral environment, leading to plaque accumulation and changes in microbial colonization. This study aimed to assess microbiological changes in 10 to 16-year-old children undergoing fixed orthodontic treatment.

Methodology

The study included children aged 10-16 years, with one group wearing fixed orthodontic appliances and a control group without brackets. Data on salivary pH, buffer capacity, Streptococcus mutans, and Lactobacillus spp were collected at baseline and after 6 months. Logistic regression models evaluated associations between orthodontic treatment and elevated bacterial levels, adjusting for age, gender, pH, and buffer capacity.

Results

Wearing fixed orthodontic appliances was significantly associated with elevated Streptococcus mutans (aOR: 6.62, 95% CI: 1.91-21.88) and Lactobacillus spp (aOR: 9.49, 95% CI: 2.57-35.07). Gender showed a significant association with Lactobacillus spp levels (aOR: 0.28, 95% CI: 0.09-0.87).

Conclusion

Fixed orthodontic appliances significantly impact oral microbial changes, underscoring the need for proper oral hygiene during orthodontic treatment to reduce dental caries risk.

Radiation-associated changes in saliva composition of head and neck cancer patients: A systematic review

Xerostomia is a common radiation-associated toxicity in patients with head and neck cancer. Although several studies examined the decrease in saliva production due to radiotherapy (RT) and investigated the factors associated with this side effect, little is known about the change in radiation-associated saliva composition. This systematic review is the first to summarize existing data and give an overview of the change in pH/buffer capacity, electrolytes, proteins, enzymes, and mucins due to radiation to the salivary glands. Literature search was performed in PubMed and Embase with 47 articles finally eligible for the review, analyzing the saliva composition at several time points before, during and/or after RT, or comparing findings in irradiated patients to a healthy control group. Overall, RT leads to a substantial decrease in salivary pH and buffer capacity. For sodium, chloride and calcium ion, as well as amylase, an increased concentration or activity during RT was reported in most of the studies, followed by a subsequent decrease either already during RT or after the end of treatment. Different trends have been described for the total protein concentration during and after RT. Lactoferrin, however, increased considerably, especially in the first phase of RT. Mucin 5B (MUC5B) concentrations showed a slight increase during RT and concentrations around baseline values again six months post-radiotherapy.

Functionalization of a zirconia surface by covalently immobilized fibronectin and its effects on resistance to thermal, acid, and mechanical exposure

Silane chemistry has emerged as a powerful tool for surface modification, offering a versatile means to enhance the properties of various substrates, such as dental implant abutment materials. In this study, we investigated the stability of the 3-aminopropyldiisopropylethoxysilane (APDS) layer on yttria-partially stabilized zirconia (Y-TZP) surfaces after mechanical, acid, and thermal treatment in order to simulate fluctuations within the oral cavity. To accomplish that, the viability of human gingival fibroblasts on APDS-modified surfaces after applied treatment strategies was assessed by live/dead staining. Moreover, the hydrolysis stability and enzymatic degradation resistance of crosslinked fibronectin to the APDS layer was examined by immunostaining and western blot. The results revealed that the applied modifications were not affected by the different treatment conditions and could withstand the fluctuations in the oral cavity. Furthermore, crosslinked fibronectin on silanized Y-TZP was stable against hydrolysis over 21 days and enzymatic degradation. We thus can conclude that the proposed functionalization method has high potential to tolerate harmful effects within the oral cavity and remains unchanged on the surface.

Proteomic analysis of stimulated saliva in gastroesophageal reflux disease patients with and without erosive tooth wear: Observational study

OBJECTIVE

To evaluate the difference in the proteomic profile of stimulated saliva in patients with gastroesophageal reflux disease (GERD) with (GE) and without (GNE) erosive tooth wear (ETW), regarding both human and bacterial proteins.

METHODS

Stimulated saliva (SS) was collected from 16 patients (8/group). Samples were centrifuged at 4.500 g for 15 min under refrigeration to remove all debris. The supernatant from each saliva sample was taken and frozen at -80 °C. After extracting the proteins, they were submitted to reverse phase liquid chromatography and mass spectrometry (nLC-ESI-MS/MS). Label-free proteomic quantification was performed using Protein Lynx Global Service (PLGS) software (p < 0.05) for human and bacterial proteins.

RESULTS

In total, 67 human proteins were common for GNE and GE groups. GNE group presented, compared to GE group, increase in proteins that confer antimicrobial and acid resistant properties, such as cystatins, histatin and immunoglobulins. However, GNE group had a marked decrease in subunits of hemoglobin (α, β and delta). Regarding bacterial proteins, for SS, 7 and 10 unique proteins were identified in the GE and GNE groups, respectively. They are related to protein synthesis and energy metabolism and interact with human proteins typically found in saliva and supramolecular complexes of the acquired pellicle.

CONCLUSIONS

Our data indicate that the stimulation of the salivary flow increases acid resistant and antimicrobial proteins in saliva, which might protect against ETW.

CLINICAL SIGNIFICANCE

This pioneer study showed important differences in the human and bacterial proteome of SS in patients with GERD with or without ETW.

Berberine-fluconazole microparticle-based combination therapy to treat candidiasis infections

AIM

This study aims to incorporate alginate microparticles containing berberine and fluconazole into two different types of pharmaceutical formulations, to subsequently evaluate the antifungal activity against Candida albicans.

METHODS AND RESULTS

Alginate microparticles containing BBR (berberine) and FLU (fluconazole) were produced by the spray-drying technique, characterized and incorporated in two pharmaceutical formulations, a vaginal cream and artificial saliva. Broth microdilution, checkerboard, time-kill curve, and scanning electron microscopy were carried out to determine the antifungal effects of BBR and FLU against C. albicans. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values of free BBR were 125 μg ml-1. Synergism between BBR and FLU was demonstrated by a fractional inhibitory concentration index (FICI) = 0.0762. The time-kill curve for the combination BBR + FLU showed a more pronounced decrease in fungal growth in comparison to free drugs, and an antibiofilm effect of BBR occurred in the formation and preformed biofilm.

CONCLUSION

Alginate microparticles containing BBR and FLU were obtained and incorporated in a vaginal cream and artificial saliva. Both formulations showed good stability, antifungal effects, and organoleptic characteristics, which suggest that BBR-FLU microparticles in formulations have potential as antifungal therapy.

Incorporation of bioactive glass-ceramic into coconut oil for remineralization of incipient carious lesions

This study evaluated the efficacy of incorporating different concentrations of bioactive glass-ceramic (Biosilicate) into coconut oil on the remineralizing potential and surface roughness of white spot lesions. Fragments (6 x 6 x 2mm) of bovine teeth were sectioned and initial microhardness (KHN) and surface roughness (Ra) readings were obtained. The samples were submitted to cariogenic challenge to form white spot lesions and were separated into six groups (n=13): 1) Artificial Saliva (AS); 2) Coconut Oil (CO); 3) CO+2% Biosilicate (CO+2%Bio); 4) CO+5% Biosilicate (CO+5%Bio); 5) 2% Biosilicate Suspension (2% Bio) and 6) 5% Biosilicate Suspension (5% Bio). The treatments for 1 cycle/day were: immersion into the treatments for 5 minutes, rinsing in distilled water, and storage in artificial saliva at 37ºC. After 14 days, KHN and Ra readings were taken. The surface roughness alteration ((Ra) was analyzed (Kruskal-Wallis, Dunn's post-test, p<0.05). CO+2%Bio had higher (p = 0.0013) (Ra followed by CO+5%Bio (p = 0.0244) than AS. The relative KHN and remineralization potential were analyzed (ANOVA, Tukey, p<0.05), and 5% Bio treatment presented a higher relative microhardness than all other groups (p>0.05). The remineralizing potential of all the treatments was similar (p > .05). When Biosilicate was added, the pH of the suspensions increased and the alkaline pH remained during the analysis. Biosilicate suspension is more efficient than the incorporation of particles into coconut oil at white spot lesion treatment. In addition to the benefits that coconut oil and Biosilicate present separately, their association can enhance the remineralizing potential of Biosilicate.

Interactive Effect of Salivary Protein Carbonyl, Total Glutathione, pH, and Flow Rate on Root Caries Severity: A Case-Control Study

Aims and Objectives

Oxidant and antioxidant components in saliva play an essential role in caries development. The purpose of the current study was to disclose the interactive effect of salivary protein carbonyl (PC), total glutathione (GSH), pH, and flow rate on root caries severity.

Materials and Methods

The control and study groups consisted of 90 older adults of both genders classified into six groups: normal salivary flow rate with no root caries (control), normal salivary flow rate with incipient root caries, normal salivary flow rate with shallow root caries, hyposalivation with no root caries, hyposalivation with incipient root caries, and hyposalivation with shallow root caries. Each group consisted of 15 older adults. The study participants were selected from those patients who attended the teaching hospital at the College of the Dentistry/University of Baghdad and fit the study's criteria. Unstimulated saliva was collected. Both salivary pH and flow rate were determined immediately. After that, saliva was subjected to biochemical analysis to determine PC and total GSH levels colorimetrically. Root surface caries was diagnosed clinically using the Root Caries Index. Data were statistically analyzed using descriptive statistics, two-way univariate analysis of variance, two-way multivariate analysis of variance, and Pearson's correlation coefficient (α = 5%).

Results

Salivary total glutathione revealed a significant interactive effect with salivary flow rate and root decay severity. Levels of salivary total GSH were significantly higher in subjects with shallow root caries than those with incipient root caries; no root caries levels of salivary PC were significantly high in the hyposalivation group, but no correlation with caries severity was found. High root caries severity was found to be associated with reduced salivary pH and flow rate.

Conclusion

A significant interactive effect was recorded for salivary flow rate, pH, and total GSH on root caries severity except for salivary PC.

Assessment of Salivary pH, Buffer Capacity, and Flow in COVID-19-Infected and Vaccinated Dental Patients

Background The impact of COVID-19 infection and immunization on salivary gland function has not yet been fully understood. Therefore, a study to determine salivary pH (SP), salivary buffer capacity (SBC), and salivary flow (SF) in COVID-19-infected and immunized patients seeking dental care is necessary. Therefore, the main goal of this study was to evaluate saliva production at five minutes, SP, and salivary SBC in COVID-19-infected and vaccinated dental patients who were undergoing treatment at a private university dental hospital in Riyadh, Saudi Arabia. Methodology Dental students at Riyadh Elm University were included in this observational study, which involved dental patients. Based on Tawakkalna application records, patients were asked to provide their COVID-19 infection and vaccination status. Mean, standard deviation, and descriptive statistics of the frequency distribution were computed. Results The study included individuals aged 18 to 39 years old, with an average age of around 28.5 years old. The sample had slightly more males than females, but the difference was not significant. In terms of COVID-19 testing, most individuals had tested positive for the virus two or three times. The most common amount of unstimulated saliva produced was 3.5 mL, with most individuals producing between 2 and 3.5 mL of saliva. According to the observations, there were substantial variations between people who tested positive and negative for the COVID-19 virus in terms of SP and buffering capacity, suggesting that these factors could be possible indications of infection. Conclusions This study also emphasizes the value of evaluating several salivary factors to enhance diagnostic precision and the possibility of saliva-based testing as a non-invasive and affordable substitute for conventional diagnostic techniques in relation to oral issues. The study does, however, have several drawbacks, such as the limited sample size and the inability to be generalized to different populations.

Antigingivitis, Desensitizing, and Antiplaque Effects of Alkaline Toothpastes: A Randomized Clinical Trial

Gingivitis is a widespread disease commonly associated with dentin hypersensitivity, that, in turn, may complicate routine dental care, leading to plaque accumulation. We aimed to assess the antigingivitis, desensitizing, and antiplaque effects of a fluoride-containing (TWF) alkaline toothpaste and a fluoride-free (TW) alkaline toothpaste. Eighty-four consenting patients aged 20-25 years with diagnosed gingivitis and dentin hypersensitivity (DH) were recruited in this double-blind, parallel-group study and randomly divided into two groups (each n = 42). Eighty-two patients completed the entire study protocol. The outcomes were assessed after 4 weeks of intervention. A significant improvement in gingival condition was found according to the modified gingival index, with effect sizes of 0.99 [CI95%: 0.52-1.46] and 1.71 [CI95%: 1.18-2.24], and the gingival bleeding index, with effect sizes of 3.17 [CI95%: 2.39-3.94] and 2.64 [CI95%: 1.96-3.32] in the TW and TWF groups, respectively. DH also decreased in both groups, with a significantly greater reduction in the TWF group (effect sizes of 3.28 [CI95%: 2.51-4.04] and 3.10 [CI95%: 2.40-3.80] according to the visual analog scale and Schiff scale, respectively). No side effects were registered. In conclusion, the use of alkaline toothpaste provided a significant reduction in gingival inflammation and bleeding, DH, and oral hygiene after 4 weeks of daily use in young adults. Trial Registration: NCT0562376. Funding: none.

Gastroesophageal reflux disease and oral symptoms: A two-sample Mendelian randomization study

Background: The association between Gastroesophageal reflux disease (GERD) and oral symptoms has been reported in observational studies, but the causality of GERD to oral symptoms remained unknown. We aimed to assess the causal effect of GERD on five oral symptoms (mouth ulcers, toothache, loose teeth, bleeding gums, and periodontitis) using the two-sample Mendelian randomization (MR) method. Methods: Summary-level statistics for GERD and five oral symptoms were obtained from large-scale genome-wide association studies. Rigorous quality control of genetic instruments was conducted before MR analysis. Several analytical methods, including the inverse-variance weighted (IVW) method, MR-Egger regression, weighted median, maximum likelihood, and robust adjusted profile score (RAPS) were utilized, and the results of IVW were taken as the main results. The MR-Egger intercept test, Cochran's Q test, and leave-one-out test were used as sensitivity analysis for quality control. Results: After Bonferroni, IVW detected a significant effect of GERD on mouth ulcers (OR = 1.008, 95% CI = 1.003-1.013, p = 0.003), loose teeth (OR = 1.009, 95% CI = 1.005-1.012, p = 9.20 × 10^-7), and periodontitis (OR = 1.229, 95% CI = 1.081-1.398, p = 0.002). Consistent patterns of associations were observed across several MR models and sensitivity analysis found little evidence of bias. Nominal significant associations were observed in toothache and bleeding gums (p < 0.05), and heterogeneity was detected. Conclusion: Our MR analyses supported the positive causal effect of GERD on oral symptoms, especially for mouth ulcers, loose teeth, and periodontitis. Our findings might shed light on the mechanism of oral disease and might imply that oral care should be enhanced in patients with GERD.

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.

Alternative Antibiotics in Dentistry: Antimicrobial Peptides

The rise of antibiotic resistant bacteria due to overuse and misuse of antibiotics in medicine and dentistry is a growing concern. New approaches are needed to combat antibiotic resistant (AR) bacterial infections. There are a number of methods available and in development to address AR infections. Dentists conventionally use chemicals such as chlorohexidine and calcium hydroxide to kill oral bacteria, with many groups recently developing more biocompatible antimicrobial peptides (AMPs) for use in the oral cavity. AMPs are promising candidates in the treatment of (oral) infections. Also known as host defense peptides, AMPs have been isolated from animals across all kingdoms of life and play an integral role in the innate immunity of both prokaryotic and eukaryotic organisms by responding to pathogens. Despite progress over the last four decades, there are only a few AMPs approved for clinical use. This review summarizes an Introduction to Oral Microbiome and Oral Infections, Traditional Antibiotics and Alternatives & Antimicrobial Peptides. There is a focus on cationic AMP characteristics and mechanisms of actions, and an overview of animal-derived natural and synthetic AMPs, as well as observed microbial resistance.

Toxicological Assessment of an Acrylic Removable Orthodontic Appliance Using 2D and 3D In Vitro Methods

Malocclusion is a global health problem, mainly affecting children and adolescents. For this reason, orthodontic treatment must be, on the one hand, safe, non-toxic, and effective and, on the other hand, it must have the best possible esthetic profile. Thus, the use of orthodontic appliances is addressed to all age groups, including young children, for a long period of time, which is why their safety profile is a matter of real interest. For this reason, the purpose of the present study was to evaluate the safety and biocompatibility of an acrylic removable orthodontic appliance made of polymethylmethacrylate and stainless steel alloy made by our team of researchers. To verify the biocompatibility of the medical device, it was immersed in artificial saliva with three different pHs (3, 7, and 10) for a period of ten days. Subsequently, the three types of saliva were tested on human keratinocytes (HaCaT cell line) in terms of viability and modification of cell morphology. Finally, the use of 3D reconstructed human epidermis verified the cytotoxic and irritating potential of the medical device, thus providing relevant information regarding its biocompatibility. The results revealed that by maintaining the orthodontic device in the saliva there is no release of substances with a toxic effect on the human keratinocytes and on the 3D reconstructed human epidermis. There were also no significant changes in cell morphology. In conclusion, it is suggested that the acrylic removable appliance has a safety profile recommended for in vivo use.