The oral microbiome: Its role in health and in oral and systemic infections

The association between dental caries and steroid-sensitive nephrotic syndrome in children

BACKGROUND

Pathogenesis and relapse of steroid-sensitive nephrotic syndrome (SSNS) are primarily associated with infection. Dental caries is the most common chronic progressive oral infection in children. However, clinical studies of SSNS combined with dental caries in children are rare.

METHODS

In our retrospective cohort study from January 2021 to June 2022, 145 children with SSNS were included in the baseline analysis and 105 in the follow-up analysis. The follow-up period was 1 year. The primary study endpoints were the relapse-free period and frequently relapsing nephrotic syndrome (FRNS). Secondary endpoints included the number and triggers of relapses and concomitant medications.

RESULTS

The median age was 5.5 years, with a caries rate of 60.7%, the mean DMFT/dmft was 3.86, and the caries filling rate was 1.6%. Except for the lower proportion of high household income and high parental education observed in the caries group, no statistical differences were found when comparing the other baseline data with the non-caries group. The caries group had a shorter relapse-free period and a lower 1-year cumulative relapse-free survival rate (HR = 1.90, 95% CI 1.17-3.09, P = 0.009). Univariate regression analysis showed caries associated with FRNS (OR = 2.714, 95% CI 1.021-7.219, P = 0.045), but the correlation no longer remained in the multivariate analysis. Additionally, seven cases of caries-derived pulpal periapical inflammation triggered SSNS relapses. The caries group had more infection triggers and concomitant medication use.

CONCLUSION

Dental caries and relapse of SSNS are potentially associated, but careful evaluation is needed.

Association between peri-implantitis and systemic inflammation: a systematic review

Background

Peri-implantitis is an infectious/inflammatory disease with similar clinical and radiographic features to periodontitis. Overwhelming evidence confirmed that periodontitis causes elevations in systemic inflammatory mediators; this is unclear for peri-implantitis. Hence, this study aimed to appraise all available evidence linking peri-implantitis with systemic inflammation.

Methods

A systematic review was completed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Eight electronic databases (Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, Web of Science, Dentistry & Oral Sciences Source, Scopus, LILACS, and China Online), ClinicalTrials.gov, WHO International Clinical Trials Registry Platform (ICTRP), and gray literature were searched up to February 9, 2023. Human studies of randomized controlled trials, non-randomized intervention studies, cohort studies, case-control, and cross-sectional studies were eligible for inclusion. Quantitative analyses were performed using random effects models.

Results

A total of 27 full-text articles were retrieved, and 11 clinical studies were included in the final analyses. All evidence gathered demonstrated a consistent association between peri-implantitis and systemic inflammation. Patients with peri-implantitis exhibited higher levels of serum C-reactive protein (CRP) (standard mean difference (SMD): 4.68, 98.7% CI: 2.12 to 7.25), interleukin-6 (IL-6) (weighted mean difference (WMD): 6.27 pg/mL, 0% CI: 5.01 to 7.54), and white blood cell counts (WMD: 1.16 * 103/μL, 0% CI: 0.61 to 1.70) when compared to participants without peri-implantitis.

Conclusion

Peri-implantitis is associated with higher systemic inflammation as assessed by serum CRP, IL-6, and white blood cell counts. Further research is needed to clarify the nature of this association.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=246837, identifier CRD42021246837.

Effect of polydopamine and fluoride ion coating on dental enamel remineralization: an in vitro study

BACKGROUND

Fluoride treatment is one of the most effective dental caries prevention methods. To continuously prevent dental caries, stably immobilizing the fluoride on the tooth enamel is highly desirable. This study aimed to evaluate the remineralization of tooth enamels by one-pot coating using polydopamine and fluoride ions.

METHODS

To prepare the enamel specimens for polydopamine- and fluoride ion-coating, they were treated with polydopamine- and fluoride-containing gels. The enamel specimens were collected from human molars in a blind manner (n = 100) and were randomized into five treatment groups (n = 20, each): 1) untreated, 2) polydopamine-coated, 3) fluoride-containing gel-treated, 4) F varnish-treated, and 5) polydopamine- and fluoride ion-coated enamels. Vickers hardness number (VHN), morphology, and fluoride contents of the specimens were measured before and after the pH-cycling regimen.

RESULTS

Polydopamine- and fluoride ion-coated enamels showed the highest fluoride content and lowest VHN reduction among the samples. The fluoride content of the polydopamine/fluoride ion (PD/F)-coated enamel was increased to 182 ± 6.6%, which was far higher than that of the uncoated enamel (112.3 ± 32.8%, P < 0.05). The changes in the VHN values (ΔVHN) of PD/F-coated enamel substrates showed a slight reduction in the VHN (-3.6%, P < 0.05), which was far lower than that in the control group (-18.9%, P < 0.05). In addition, scanning electron microscopy clearly supported the effect of polydopamine- and fluoride ion-coatings on the remineralization of enamel specimens.

CONCLUSION

Our findings suggest that one-pot treatments with polydopamine and fluoride ions could significantly enhance remineralization by inhibiting enamel demineralization through the prolonged retention of fluoride ions.

Glycerol metabolism supports oral commensal interactions

During oral biofilm development, interspecies interactions drive species distribution and biofilm architecture. To understand what molecular mechanisms determine these interactions, we used information gained from recent biogeographical investigations demonstrating an association of corynebacteria with streptococci. We previously reported that Streptococcus sanguinis and Corynebacterium durum have a close relationship through the production of membrane vesicle and fatty acids leading to S. sanguinis chain elongation and overall increased fitness supporting their commensal state. Here we present the molecular mechanisms of this interspecies interaction. Coculture experiments for transcriptomic analysis identified several differentially expressed genes in S. sanguinis. Due to its connection to fatty acid synthesis, we focused on the glycerol-operon. We further explored the differentially expressed type IV pili genes due to their connection to motility and biofilm adhesion. Gene inactivation of the glycerol kinase glpK had a profound impact on the ability of S. sanguinis to metabolize C. durum secreted glycerol and impaired chain elongation important for their interaction. Investigations on the effect of type IV pili revealed a reduction of S. sanguinis twitching motility in the presence of C. durum, which was caused by a decrease in type IV pili abundance on the surface of S. sanguinis as determined by SEM. In conclusion, we identified that the ability to metabolize C. durum produced glycerol is crucial for the interaction of C. durum and S. sanguinis. Reduced twitching motility could lead to a closer interaction of both species, supporting niche development in the oral cavity and potentially shaping symbiotic health-associated biofilm communities.

Multi-Omic Factors Associated with Frequency of Upper Respiratory Infections in Developing Infants

Susceptibility to upper respiratory infections (URIs) may be influenced by host, microbial, and environmental factors. We hypothesized that multi-omic analyses of molecular factors in infant saliva would identify complex host-environment interactions associated with URI frequency. A cohort study involving 146 infants was used to assess URI frequency in the first year of life. Saliva was collected at 6 months for high-throughput multi-omic measurement of cytokines, microRNAs, transcripts, and microbial RNA. Regression analysis identified environmental (daycare attendance, atmospheric pollution, breastfeeding duration), microbial (Verrucomicrobia, Streptococcus phage), and host factors (miR-22-5p) associated with URI frequency (p < 0.05). These results provide pathophysiologic clues about molecular factors that influence URI susceptibility. Validation of these findings in a larger cohort could one day yield novel approaches to detecting and managing URI susceptibility in infants.

Better oral hygiene is associated with a reduced risk of cataract: A nationwide cohort study

Objective

To investigate the association of oral health status and oral hygiene behaviors with cataract occurrence longitudinally.

Materials and methods

Based on the National Health Screening cohort database of Korea, participants who underwent oral health screening by dentists in 2003 were included. Cataract was defined as two or more claims of disease classification for the International Classification of Diseases-10 (E10.34, E11.34, E12.34, E13.34, E14.34, H25, and H26) with cataract specific treatment or surgery procedure claim codes. The occurrence of cataract was analyzed with Cox proportional hazard model according to the presence of periodontitis and oral health examination findings, including missing teeth, caries, tooth brushing, and dental scaling.

Results

Overall, 103,619 subjects were included. During a median follow-up of 12.2 years, cataract developed in 12,114 (11.7%) participants. Poor oral health status such as the presence of periodontitis (adjusted hazard ratio [HR] 1.08, 95% CI [confidence interval] 0.99-1.17, p = 0.088) and increased number of missing teeth (adjusted HR = 1.74, 95% CI = 1.55-1.96, p < 0.001) was associated with the increased cataract risk. Better oral hygiene behaviors such as increased frequency of tooth brushing (adjusted HR = 0.84, 95% CI = 0.79-0.88, p < 0.001) and performed dental scaling within 1 year (adjusted HR = 0.90, 95% CI = 0.86-0.94, p < 0.001) were negatively associated with cataract occurrence.

Conclusion

Periodontitis and increased number of missing teeth may increase the risk of cataract. However, maintaining good oral hygiene through tooth brushing and dental scaling may reduce the risk of future cataract occurrence. Further studies should be performed to confirm the association between chronic oral inflammation and cataract.

Oral microbiota in cancer: could the bad guy turn good with application of polyphenols?

The human oral cavity is comprised of dynamic and polynomial microbes which uniquely reside in the microenvironments of oral cavities. The cumulative functions of the symbiotic microbial communities maintain normal homeostasis; however, a shifted microbiota yields a dysbiosis state, which produces local and systemic diseases including dental caries, periodontitis, cancer, obesity and diabetes. Recent research reports claim that an association occurs between oral dysbiosis and the progression of different types of cancers including oral, gastric and pancreatic ones. Different mechanisms are proposed for the development of cancer, such as induction of inflammatory reactions, production of carcinogenic materials and alteration of the immune system. Medications are available to treat these associated diseases; however, the current strategies may further worsen the disease by unwanted side effects. Natural-derived polyphenol molecules significantly inhibit a wide range of systemic diseases with fewer side effects. In this review, we have displayed the functions of the oral microbes and we have extended the report regarding the role of polyphenols in oral microbiota to maintain healthy conditions and prevention of diseases with emphasis on the treatment of oral microbiota-associated cancer.

Pharmacological Efficacy of Probiotics in Respiratory Viral Infections: A Comprehensive Review

Mortality and morbidity from influenza and other respiratory viruses are significant causes of concern worldwide. Infections in the respiratory tract are often underappreciated because they tend to be mild and incapacitated. On the other hand, these infections are regarded as a common concern in clinical practice. Antibiotics are used to treat bacterial infections, albeit this is becoming more challenging since many of the more prevalent infection causes have acquired a wide range of antimicrobial resistance. Resistance to frontline treatment medications is constantly rising, necessitating the development of new antiviral agents. Probiotics are one of several medications explored to treat respiratory viral infection (RVI). As a result, certain probiotics effectively prevent gastrointestinal dysbiosis and decrease the likelihood of secondary infections. Various probiotic bacterias and their metabolites have shown immunomodulating and antiviral properties. Unfortunately, the mechanisms by which probiotics are effective in the fight against viral infections are sometimes unclear. This comprehensive review has addressed probiotic strains, dosage regimens, production procedures, delivery systems, and pre-clinical and clinical research. In particular, novel probiotics’ fight against RVIs is the impetus for this study. Finally, this review may explore the potential of probiotic bacterias and their metabolites to treat RVIs. It is expected that probiotic-based antiviral research would be benefitted from this review’s findings.

Effects of Long-Term Enclosed Environment on Human Health Based on the Analysis of Salivary Microbiota and Cytokines

Long-term exposure to space environments may influence the human microbiome, the human immune system, and the intricate balance between the two, causing impaired immunity and increased disease susceptibility. It was previously believed that the main potential factors of long-term spaceflight on human health were microgravity and radiation.

Probiotics-Mediated Bioconversion and Periodontitis

Novel bioactive metabolites have been developed through a bioconversion of dairy products or other foods using probiotics isolated from dairy products or other fermented foods. These probiotics-mediated bioconversion (PMB) metabolites show antioxidant, anti-inflammatory, antimicrobial, epithelial barrier, and anticancer activities. In addition, the effect of PMB metabolites in periodontitis is recently reported in several studies. Periodontitis is a chronic inflammatory disease caused by infections, and the tooth support tissue is destroyed. Common treatments for periodontitis include scaling and root planning with systemic antibiotics. However, the overuse of antibiotics has led to the emergence of drug-resistant microorganisms and disturbs the beneficial bacteria, including lactobacilli in the oral cavity. For this reason, PMB metabolites, such as fermented milk, have been suggested as substitutes for antibiotics to reduce periodontitis. This paper reviews the recent studies on the correlation between periodontitis and PMB metabolites and classifies the efficacy of major PMB metabolites for periodontitis. The review suggests that PMB is effective for periodontitis, and further studies are needed to confirm the therapeutic effect of PMB metabolites on periodontitis.

The Influence of the Use of Face Masks During the COVID-19 Pandemic on the Human Microbiome – A Mini-Review

The aim of this study was to draw attention to the possible consequences of improper, unhygienic use of mouth and nose covers in the context of prophylaxis against the spread of COVID-19 from the point of view of a family physician and focus on the risk of respiratory infections and skin lesions in patients, in different age groups. The use of protective masks may reduce the likelihood of infection but will not eliminate the risk of infection. However, it should be remembered that any mask, no matter how effective the filtration is or how well it seals, will have little effect if not used in conjunction with other preventive measures, including isolation of infected people, immunization, proper respiratory culture, regular, frequent replacement of masks, and hand hygiene. Additionally, certain risks associated with this form of prophylaxis should be taken into account, which, unfortunately, may also aggravate or even constitute a source of serious respiratory infections and lead to the development and aggravation of skin problems. Moreover, educating society not only on hand hygiene but also on the topic of the value of nose and mouth covers, as well as the frequency of their replacement and/or disinfection, is becoming a significant issue.

Combating Biofilm by Targeting Its Formation and Dispersal Using Gallic Acid against Single and Multispecies Bacteria Causing Dental Plaque

Exploring biological agents to control biofilm is a vital alternative in combating pathogenic bacteria that cause dental plaque. This study was focused on antimicrobial, biofilm formation and biofilm dispersal efficacy of Gallic acid (GA) against bacteria, including Proteus spp., Escherichia coli, Pseudomonas spp., Salmonella spp., Streptococcus mutans, and Staphylococcus aureus and multispecies bacteria. Biofilm was qualitatively and quantitatively assessed by crystal violet assay, florescence microscopy (bacterial biomass (µm²), surface coverage (%)) and extracellular polymeric substances (EPS). It was exhibited that GA (1-200 mg/L) can reduce bacterial growth. However, higher concentrations (100-200 mg/L) markedly reduced (86%) bacterial growth and biofilm formation (85.5%), while GA did not exhibit any substantial dispersal effects on pre-formed biofilm. Further, GA (20-200 mg/L) exhibited 93.43% biomass reduction and 88.6% (p < 0.05) EPS (polysaccharide) reduction. Microscopic images were processed with BioImageL software. It was revealed that biomass surface coverage was reduced to 2% at 200 mg/L of GA and that 13,612 (µm²) biomass was present for control, while it was reduced to 894 (µm²) at 200 mg/L of GA. Thus, this data suggest that GA have antimicrobial and biofilm control potential against single and multispecies bacteria causing dental plaque.

Periodontitis and Systemic Lupus Erythematosus: A systematic review and meta-analysis

This systematic review and meta-analysis evaluated the association between periodontitis (PD) and systemic lupus erythematosus (SLE). A systematic search was conducted through the following electronic databases: Cochrane Library, MEDLINE, EMBASE, Scopus, LILACS, CINAHL and SIGLE (System for Information on Grey Literature in Europe) for relevant publications up to September 2020 with no language restriction. The association between PD and SLE was assessed by the prevalence of PD in SLE patients (both sex and females only) as the primary outcome. Secondary outcomes included differences in common gingival parameters including probing pocket depth (PPD), clinical attachment level (CAL), disease activity index (SLEDAI) scores of SLE patients with or without PD. A total of 1183 citations and 22 full text articles were screened. Eighteen articles were included in the qualitative synthesis, and 13 in the quantitative analysis. SLE diagnosis was associated with greater odds of PD (OR = 1.33, 95% Confidence Interval [CI]: 1.20-1.48), but these were non-significant when examined in females (OR = 3.20, 95%CI: 0.85-12.02). Patients with SLE exhibited no differences in PPD (SMD: -0.09 mm, 95%CI: -0.45-0.27) and CAL (SMD: 0.05 mm, 95%CI: -0.30-0.40) when compared with systemically healthy controls. PD diagnosis was, however, associated with higher SLEDAI scores in patients suffering from SLE (SMD: 0.68, 95% CI: 0.03-1.32). PD and SLE are both inflammatory diseases and their association could be bi-directional. This review suggested that the patients with SLE have greater odds of suffering with PD. Further investigations are required to assess the association between PD and SLE.

Associations between dental caries and systemic diseases: a scoping review

BACKGROUND

The objective of this study was to evaluate and present evidence from animal and human clinical studies on associations between dental caries and systemic diseases, and to suggest potential mechanisms that might explain such associations.

METHODS

An electronic search was conducted of PubMed, Embase and Cochrane Central Register of Controlled Trials for articles published from 2010 to 2020 in the English language. From the initial search, 404 full-text studies were assessed for eligibility. After excluding studies for technical and study limitations, a total of 67 studies were included in the summary tables and additional studies were included in the review to support evidence.

RESULTS

Few systemic disease and conditions were found to be clinically meaningfully associated with caries experience. Best evidence from human and animal studies described association between metabolic diseases and dental caries. Several interesting animal studies were noted that could generate clinical hypotheses and further investigations in rodent models for cardiovascular injury and hyperglycemia. Inadequate data was found to suggest any modifications to current clinical practice or prevention guidelines.

CONCLUSIONS

Limited clinical evidence was found connecting several systemic diseases and dental caries. Inadequate data was found to suggest any modifications to current clinical practice or prevention guidelines.

CLINICAL SIGNIFICANCE

Understanding of associations between dental caries and systemic diseases play a crucial role in the treatment planning and education of the dental patient.

Identification & correlation of bacterial diversity in oral cancer and long-term tobacco chewers- A case-control pilot study

Introduction. Squamous cell carcinoma is a highly aggressive type of oral cancer (OC). It is the most common cancer among men, and accounts for almost 90 % of all oral cancers in India. Consumption of tobacco is a leading factor contributing to maximum oral cancer incidences as per the WHO.Hypothesis/Gap statement. Researchers reported a direct association of microorganisms with dysbiosis in various oral lesions including oral cancer. However, there is a dearth of information related to compositional changes in the oral microbiome in long-term tobacco chewers and the Indian oral cancer population.Aim. The aim of this study was to identify and correlate the bacterial diversity in the oral cavity of tobacco chewers, patients with oral cancer and healthy subjects in the Indian population.Methods. Oral rinse samples were collected for ten subjects in each group followed by DNA extraction. The variable regions of the bacterial 16S rRNA gene (V6-V8) were amplified, sequenced, processed, and analysed using QIIME2 platform to assess alpha and beta diversity between the study groups.Results. This pilot study showed genus Streptococcus dominated the control group (18.54 %), and the abundance decreased in tobacco and OC group (9.63 and 5.45% respectively); whereas genus Prevotella dominated the tobacco and OC group (21.01 and 26.03% respectively). A shift in abundance of microbiome was observed from control population to oral cancer via the tobacco chewing population. Maximum alpha diversity of oral microbiome was found in Indian tobacco chewers. Beta diversity of tobacco chewers was similar to both the healthy population as well as oral cancer patients suggesting transitioning of the oral microbiome from healthy to oral cancer microbiome via the tobacco chewers microbiome.Conclusion. The data provides evidence of oral bacterial dysbiosis due to tobacco chewing habits that can further lead to progression towards cancer.

Microbiome and Cancers of the Esophagus: A Review

Esophageal cancer (EC) is an aggressive malignant disease ranking amongst the leading causes of cancer deaths in the world. The two main histologic subtypes, esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC), have distinct geographic and temporal patterns and risk factor profiles. Despite decades of research, the factors underlying these geo-temporal patterns are still not fully understood. The human microbiome has recently been implicated in various health conditions and disease, and it is possible that the microbiome may play an important role in the etiology of EC. Although studies of the microbiome and EC are still in their early stages, we review our current understanding of the potential links between ESCC, EAC, and bacterial communities in the oral cavity and esophagus. We also provide a summary of the epidemiology of EC and highlight some key challenges and future directions.

Antimicrobial Resistance and the Spectrum of Pathogens in Dental and Oral-Maxillofacial Infections in Hospitals and Dental Practices in Germany

Data on microbiological profiles in odontogenic infections are scarce. This study aimed to analyze the spectrum of pathogens and antimicrobial resistance in clinical isolates from dental and oral-maxillofacial clinical settings in Germany. We analyzed 20,645 clinical isolates (dental practices: n = 5,733; hospitals: n = 14,912) from patients with odontogenic infections using data (2012-2019) from the German Antimicrobial-Resistance-Surveillance (ARS) system. A total of 224 different species from 73 genera were found in clinical isolates from dental practices, and 329 different species from 97 genera were identified in isolates from hospital patients. In both hospitals and dental practices Streptococcus spp. (33 and 36%, respectively) and Staphylococcus spp. (21 and 12%, respectively) were the most frequently isolated microorganisms. In Streptococcus spp. isolates from hospitals, penicillin and aminopenicillin resistance proportions were 8.0% (95%CI 4.7-14.9%) and 6.9% (95%CI 4.7-9.9%), respectively. Substantially lower resistance proportions of penicillin and aminopenicillin were observed in dental practices [2.6% (95%CI 1.4-4.7%) and 2.1% (95%CI 1.1-4.0%), respectively]. Among Staphylococcus aureus isolates from hospital patients methicillin resistance proportions were 12.0% (95%CI 9.7-14.8%), which was higher than in isolates from dental practices (5.8% (95%CI 4.1-8.1%)]. High clindamycin and macrolide resistance proportions (>17%) were observed in Streptococcus spp. and Staphylococcus aureus isolates. In Klebsiella spp. isolates carbapenem resistance proportions were <1%. In sum, substantial antibiotic resistance was observed in isolates from odontogenic infections, which calls for strengthened efforts in antibiotic stewardship and infection prevention and control measures in both hospitals and dental practices.

Original Research: Oral Care as Prevention for Nonventilator Hospital-Acquired Pneumonia: A Four-Unit Cluster Randomized Study

BACKGROUND

Nonventilator hospital-acquired pneumonia (NV-HAP) presents a serious and largely preventable threat to patient safety in U.S. hospitals. There is an emerging body of evidence on the effectiveness of oral care in preventing NV-HAP.

PURPOSE

The primary aim of this study was to determine the effectiveness of a universal, standardized oral care protocol in preventing NV-HAP in the acute care setting. The primary outcome measure was NV-HAP incidence per 1,000 patient-days.

METHODS

This 12-month study was conducted on four units at an 800-bed tertiary medical center. Patients on one medical and one surgical unit were randomly assigned to receive enhanced oral care (intervention units); patients on another medical and another surgical unit received usual oral care (control units).

RESULTS

Total enrollment was 8,709. For the medical control versus intervention units, oral care frequency increased from a mean of 0.95 to 2.25 times per day, and there was a significant 85% reduction in the NV-HAP incidence rate. The odds of developing NV-HAP were 7.1 times higher on the medical control versus intervention units, a significant finding. For the surgical control versus intervention units, oral care frequency increased from a mean of 1.18 to 2.02 times per day, with a 56% reduction in the NV-HAP incidence rate. The odds of developing NV-HAP were 1.6 times higher on the surgical control versus intervention units, although this result did not reach significance.

CONCLUSIONS

These findings add to the growing body of evidence that daily oral care as a means of primary source control may have a role in NV-HAP prevention. The implementation of effective strategies to ensure that such care is consistently provided warrants further study. It's not yet known what degree and frequency of oral care are required to effect favorable changes in the oral microbiome during acute care hospitalization.

Shifts in the Oral Microbiota During a Four-Week Commercial Saturation Dive to 200 Meters

During commercial saturation diving, divers live and work under hyperbaric and hyperoxic conditions. The myriads of bacteria that live in and on the human body must adjust to the resultant hyperbaric stress. In this study, we examined the shifts in bacterial content in the oral cavity of saturation divers, using a metagenomic approach to determine the diversity in the composition of bacterial phyla and genera in saliva from 23 male divers before, during, and immediately after 4 weeks of commercial heliox saturation diving to a working depth of circa 200 m. We found that the bacterial diversity fell during saturation, and there was a change in bacterial composition; with a decrease at the phylum level of obligate anaerobe Fusobacteria, and an increase of the relative abundance of Actinobacteria and Proteobacteria. At the genus level, Fusobacterium, Leptotrichia, Oribacterium, and Veillonella decreased, whereas Neisseria and Rothia increased. However, at the end of the decompression, both the diversity and composition of the microbiota returned to pre-dive values. The results indicate that the hyperoxic conditions during saturation may suppress the activity of anaerobes, leaving a niche for other bacteria to fill. The transient nature of the change could imply that hyperbaric heliox saturation has no lasting effect on the oral microbiota, but it is unknown whether or how a shift in oral bacterial diversity and abundance during saturation might impact the divers’ health or well-being.

Dental bacterial biofilm and gingival status in cystic fibrosis adult patients

Introduction: The purpose of the study conducted on cystic fibrosis (CF) patients was the bacterial plaque accumulation and the gingival condition assessment, and microbial analysis of the subgingival biofilm. Materials/Methods: The study included 22 CF adult patients and 22 healthy controls, sex and age compatible with the CF patients. The dental plaque was assessed using plaque index (PLI), and the gingival status using gingival index (GI). Analyses of the subgingival biofilm were performed by the real-time polymerase chain reaction (PCR) test. Results: The mean value of GI in CF patients was 0.39 ±0.36 and was significantly lower comparing to the healthy controls (1.02 ±0.63), PLI was similar in both the groups (1.31 ±0.69) for the study group and 1.04 ±0.62 for controls). In CF patients there was no correlation between PLI and GI, which was observed in the control group. In both the groups there was a correlation between PLI and the total number of periopathogens. Furthermore, in the control group, there was a correlation between GI and the number of periopathogens. Such a correlation was not observed in the CF patients. Conclusions: In patients with CF, the lack of correlation between the amount of tooth deposits and the gingival condition may indicate a stable, most likely pharmacologically conditioned oral biofilm ecology. Among the aetiological factors of gingivitis and periodontitis in patients with CF, the bacterial activity does not seem to be modified. However, the unsatisfactory oral hygiene found in the study participants does not exclude the possibility of disease development in the future.

Biocultural pathways linking periodontal disease expression to food insecurity, immune dysregulation, and nutrition

OBJECTIVES

In this article, we test theoretical pathways leading to and resulting from periodontal disease to better understand how periodontal disease, which is measurable in both past and present populations, integrates biocultural context and affects whole-body physiology.

METHODS

We use data from the National Health and Nutrition Examination Survey (NHANES) 2003-2004 and logistic and linear regressions to test pathways linking psychosocial stress to periodontal disease, and periodontal disease to serum vitamin C levels. We then use causal mediation analysis to test the role of mediating variables in these pathways (n = 1853 individuals).

RESULTS

Food insecurity was positively associated with periodontal disease and negatively associated with serum counts of C-reactive protein (CRP) and neutrophils. Neither CRP nor neutrophils significantly mediated the relationship between food insecurity and periodontal disease. Periodontal disease was negatively associated with serum vitamin C levels and positively associated with neutrophil counts. Neutrophils may mediate the relationship between periodontal disease and vitamin C.

CONCLUSIONS

We identify two main findings: (a) periodontal disease contributes to and may result from immune dysregulation, particularly of neutrophils, and (b) an immune response to chronic infection such as periodontal disease is metabolically expensive for the body to maintain and likely depletes serum micronutrient levels. Both micronutrient status and serum neutrophil counts affect multiple skeletal and physiological phenotypes and thus position periodontal disease in whole-body context.

Understanding value in oral health: the oral health value-based care symposium

OBJECTIVE

There are both opportunities and challenges with the implementation of oral health value-based care (OHVBC). To tackle concerns and advance conversation, a symposium was convened with subject matter experts to develop a gap analysis and capture insights into professional readiness for value-based care design.

METHODS

The symposium was convened as a private event for 46 participants over the course of one and a half days in December 2019. Thematic analyses utilized the OHVBC Readiness Framework (DentaQuest Partnership, 2019) to further codify conversations as part of the gap-analysis process. Poll Everywhere, a text messaging application that allows participants to answer questions in real time, was also employed to solicit responses.

RESULTS

Attendees of the symposium felt that OHVBC would have a large portion of market share within the next 10 years. A qualitative assessment of multiple table discussions determined that the participants developed more consensus around themes for the current state and the future-desired state than the action-planning needed to close the gap between the two. This may relate to individual ideology, and the siloed environment is still prevalent in the oral health realm. In a postsymposium survey, respondent attendees did not perceive that COVID-19 would delay or negatively impact the adoption of OHVBC and may result in accelerating its utilization.

CONCLUSION

The oral health community is experiencing multiple drivers to adopt more OHVBC within business and care models. However, there is still a lack of uniformity on how to execute this delivery model.

Oral Pathogen Porphyromonas gingivalis Can Escape Phagocytosis of Mammalian Macrophages

Macrophages are phagocytic cells that play a key role in host immune response and clearance of microbial pathogens. Porphyromonas gingivalis is an oral pathogen associated with the development of periodontitis. Escape from macrophage phagocytosis was tested by infecting THP-1-derived human macrophages and RAW 264.7 mouse macrophages with strains of P. gingivalis W83 and 33277 as well as Streptococcus gordonii DL1 and Escherichia coli OP50 at MOI = 100. CFU counts for all intracellular bacteria were determined. Then, infected macrophages were cultured in media without antibiotics to allow for escape and escaping bacteria were quantified by CFU counting. P. gingivalis W83 displayed over 60% of the bacterial escape from the total amount of intracellular CFUs, significantly higher compared to all other bacteria strains. In addition, bacterial escape and re-entry were also tested and P. gingivalis W83, once again, showed the highest numbers of CFUs able to exit and re-enter macrophages. Lastly, the function of the PG0717 gene of P. gingivalis W83 was tested on escape but found not related to this activity. Altogether, our results suggest that P. gingivalis W83 is able to significantly avoid macrophage phagocytosis. We propose this ability is likely linked to the chronic nature of periodontitis.

Probiotics-A complete oral healthcare package

Probiotics are living bacterial cells that have significant therapeutic potential for treating human infectious diseases. There is a huge market for probiotics in the pharmaceutical sector. They have been frequently used to treat the gastrointestinal diseases and improve gut immunity. In this review, the strains currently in use for manufacturing oral probiotic formulations are discussed. The review further recommends the use of probiotics for the control of various oral health disorders, like dental caries, periodontitis, gingivitis, halitosis, burning mouth syndrome, and oral cancer. Finally, this review also explores the use of various commercial probiotic products in maintaining oral health, their market values, and government acts and regulations that are relevant to the production and marketing of probiotics. Probiotics have tremendous therapeutic potential and more in-depth research must be done on these beneficial bacteria to make them one of the leading drugs in treating oral disorders.

Comparison of Oral Microbiota Collected Using Multiple Methods and Recommendations for New Epidemiologic Studies

We compared four different oral collection methods for studying the human oral microbiome: an OMNIgene ORAL kit, Scope mouthwash, nonethanol mouthwash, and Saccomanno’s fixative. Our study shows that the type of the collection method can have a large impact on the results of an oral microbiome analysis. We recommend that one consistent oral collection method should be used for all oral microbiome comparisons. While Scope and nonethanol mouthwashes are less expensive and provide results similar to those with OMNIgene, Saccomanno’s fixative may be unfavorable due to the microbial differences detected in this study. Our results will help guide the design of future oral microbiome studies.

Epidemiologic studies use various biosample collection methods to study associations between human oral microbiota and health outcomes. However, the agreement between the different methods is unclear. We compared a commercially available OMNIgene ORAL kit to three alternative collection methods: Saccomanno’s fixative, Scope mouthwash, and nonethanol mouthwash. Oral samples were collected from 40 individuals over 4 visits. Two samples were collected from each subject per visit: one with OMNIgene and one with an alternative method. DNA was extracted using the DSP DNA Virus Pathogen kit, and the V4 region of the 16S rRNA gene was PCR amplified and sequenced using MiSeq. Oral collection methods were compared based on alpha and beta diversity metrics and phylum- and genus-level relative abundances. All alpha diversity metrics were significantly lower for Saccomanno’s fixative than for OMNIgene (P < 0.001), whereas the two mouthwashes were more similar to OMNIgene. Principal-coordinate analysis (PCoA) using the Bray-Curtis and weighted UniFrac beta diversity matrices showed large differences in the microbial compositions of samples collected with Saccomanno’s compared to those with OMNIgene and the mouthwashes. Clustering by collection method was not observed in unweighted UniFrac PCoA plots, suggesting differences in relative abundances but not specific taxa detected by the collection methods. Relative abundances of most taxa were significantly different between OMNIgene and the other methods at each taxonomic level, with Saccomanno’s showing the least agreement with OMNIgene. There were clear differences in oral microbial communities between the four oral collection methods, particularly for Saccomanno’s fixative.

IMPORTANCE We compared four different oral collection methods for studying the human oral microbiome: an OMNIgene ORAL kit, Scope mouthwash, nonethanol mouthwash, and Saccomanno’s fixative. Our study shows that the type of the collection method can have a large impact on the results of an oral microbiome analysis. We recommend that one consistent oral collection method should be used for all oral microbiome comparisons. While Scope and nonethanol mouthwashes are less expensive and provide results similar to those with OMNIgene, Saccomanno’s fixative may be unfavorable due to the microbial differences detected in this study. Our results will help guide the design of future oral microbiome studies.

Challenging Precedent: Critical Care Nursing and Medical Product Innovation

In this presentation, I will share my unconventional journey, starting from my first job as a critical care staff nurse to my current role as tenure-track faculty at the University of Massachusetts Amherst, where I hold a joint position with the Institute for Applied Life Sciences and the College of Nursing. Throughout this journey, I have had many opportunities to participate in interdisciplinary clinical outcomes research and medical product development as a staff nurse, clinical nurse specialist, and project lead from the clinical, industry, and academic perspectives. While passionate about my central clinical research interests in technology innovation and its responsible use in critical and acute care, the foundation of my approach is dedicated to the values and lessons of my earliest experiences in critical care bedside nursing: supporting and preserving the dignity and humanity of person-centered patient care. Early in my career as a critical care nurse, I realized how vitally important a critical care nursing perspective could be in the design of technology for meeting the critical care needs of patients, nurses, and other professionals who provide this care. As the nation's largest group of health care professionals, nurses use more products than any other health care professional, and thus nurses have a uniquely practical and care-sensitive perspective on the development and design of medical products. Nurses, especially critical care nurses, are in a unique position to identify and address everyday health care issues, challenge assumptions and the status quo, address unrecognized and unarticulated needs, and ensure that clinical outcomes research serves as the foundation for validating the effectiveness of medical product innovation. My goal is to share lessons learned and to help participants to see the many different ways that critical care nursing knowledge can be used to improve patient care.

Insight Into the Effects of Nisin and Cecropin on the Oral Microbial Community of Rats by High-Throughput Sequencing

The oral microbiome has major impacts on oral health and disease. Antimicrobial peptides (AMPs), such as nisin and cecropin, have been widely used as food preservatives or feed additives, and are thus inevitably ingested by consumers through their oral cavity. However, as broad-spectrum antimicrobial reagents, the effect of AMPs on the oral microbiome of consumer's remains poorly characterized. In this study, we performed 16S rDNA high-throughput sequencing to investigate the effect of nisin and cecropin on the oral microbiomes of rats. Our results suggest that although nisin and cecropin have different effects on the oral microbiome of rats, both AMPs impact the composition of oral microbial communities at the phylum and genus levels. Cecropin significantly reduced the diversity and richness of rat oral microbial communities. Notably, the relative abundance of the pathogen Acinetobacter baumannii increased in the oral microbial community of rats fed cecropin-containing feed. In addition, nisin significantly reduced the amount of secretory immunoglobulin A in the saliva of rats.

Effects of Oral Commensal Streptococci on Porphyromonas gingivalis Invasion into Oral Epithelial Cells

The objective of this study was to determine if the interaction between common oral commensal bacteria and oral epithelial cells would provide protective effects against the invasion of periodontopathogen Porphyromonas gingivalis. Oral epithelial OKF6/Tert cells were used in co-cultures with Streptococcus gordonii, Streptococcus oralis, Streptococcus mitis, and Streptococcus intermedius. The viability of OKF6/Tert cells following a bacterial challenge was evaluated by trypan blue exclusion. The adherence of commensal species was determined by CFU counts. P. gingivalis invasion in OKF6/Tert cells was assessed before and after exposure to commensal species according to CFU counts. Viability assays show that only S. gordonii and S. intermedius display low toxicity toward OKF6/Tert cells. Both commensals adhere to OKF6/Tert cells at an average ratio of 1 CFU to 10 cells. P. gingivalis invasion into host cells is significantly reduced by 25% or 60% after exposure to S. gordonii or S. intermedius, respectively. The results suggest that these commensal species bind to host cells and diminish P. gingivalis invasion. This is important in the context of periodontal disease since P. gingivalis primarily acts on the host by invading it. Therefore, efforts to decrease invasion will eventually lead to future therapies harnessing the mechanisms employed by oral commensal bacteria.

Non-ventilator health care-associated pneumonia (NV-HAP): NV-HAP Risk Factors

Several risk factors have a significant impact on the development of nonventilator health care-associated pneumonia (NV-HAP). This section discusses both the modifiable and nonmodifiable risk factors contributing to the incidence of NV-HAP. Lack of mobility, malnutrition, high blood glucose, inhibition of gastric acid and central nervous system depressants underscored in this section. Efforts to treat, modify, or alter these risk factors as opportunities to decrease the incidence of NV-HAP. In addition, we to address and assess nonmodifiable risk factors.

Non-ventilator health care-associated pneumonia (NV-HAP): Best practices for prevention of NV-HAP

Although the latest research and data show decreases in many health care-associated infections, recent publications highlight the understated but significant burden of nonventilator hospital-acquired pneumonia (NV-HAP). This section presents best practices to prevent NV-HAP. Many of the tools and interventions address basic nursing care such as oral care, oral and nonoral alimentation, patient positioning and mobility, pharmacologic and immunologic controls. The section stresses the importance of working with an interdisciplinary caregiver team to address fundamental activities of daily living that mitigate risk of developing NV-HAP.

Detection of Fusobacterium in oral and head and neck cancer samples: A systematic review and meta-analysis

AIMS

This systematic review aimed to analyse: a) the presence and the abundance of Fusobacterium; b) the Fusobacterium species most often found, and c) the most common methods used for their identification in oral/head and neck cancer samples.

DESIGN

A protocol was registered on PROSPERO database. This review was conducted following PRISMA guidelines. Literature search was performed on five electronic biomedical databases, namely Pubmed, Scopus, Web of Science, Embase, and Cochrane from their start dates to 30 August 2018. Two reviewers independently assessed the eligibility for inclusion; extracted the data; and evaluated the risk of bias.

RESULTS

From 118 unique abstract records, 88 full-text articles were assessed for eligibility. According to inclusion and exclusion criteria, 17 publications were included in this review. Meta-analysis showed an increased prevalence of 6 % (95 % CI, 3-9) of Fusobacterium in tumour lesions than in non-tumour lesions (Fusobacterium prevalence of 16 % in tumour lesions and of 10 % in non-tumour lesions), and a 2.93 higher chance of Fusobacterium being present in tumour lesions (95 % CI, 1.47-5.81). The most common detection methods were based on molecular evidence (64.70 %) (95 % CI, 37.7-84.7). F. nucleatum was the most prevalent species (47.06 %) (95 % CI, 23.5-72).

CONCLUSION

In conclusion, Fusobacterium is present and in higher abundance in oral/head and neck cancer samples when compared to non-cancer samples, suggesting that Fusobacterium may contribute to oral/head and neck cancer development.

Emerging Applications of Drug Delivery Systems in Oral Infectious Diseases Prevention and Treatment

The oral cavity is a unique complex ecosystem colonized with huge numbers of microorganism species. Oral cavities are closely associated with oral health and sequentially with systemic health. Many factors might cause the shift of composition of oral microbiota, thus leading to the dysbiosis of oral micro-environment and oral infectious diseases. Local therapies and dental hygiene procedures are the main kinds of treatment. Currently, oral drug delivery systems (DDS) have drawn great attention, and are considered as important adjuvant therapy for oral infectious diseases. DDS are devices that could transport and release the therapeutic drugs or bioactive agents to a certain site and a certain rate in vivo. They could significantly increase the therapeutic effect and reduce the side effect compared with traditional medicine. In the review, emerging recent applications of DDS in the treatment for oral infectious diseases have been summarized, including dental caries, periodontitis, peri-implantitis and oral candidiasis. Furthermore, oral stimuli-responsive DDS, also known as "smart" DDS, have been reported recently, which could react to oral environment and provide more accurate drug delivery or release. In this article, oral smart DDS have also been reviewed. The limits have been discussed, and the research potential demonstrates good prospects.

Oral microbiota and autism spectrum disorder (ASD)

Autism spectrum disorder (ASD) is associated with several oropharyngeal abnormalities, including dysbiosis in the oral microbiota. Since the oral cavity is the start of the gastrointestinal tract, this strengthens and extends the notion of a microbial gut-brain axis in ASD and even raises the question whether a microbial oral-brain axis exists. It is clear that oral bacteria can find their way to the brain through a number of pathways following routine dental procedures. A connection between the oral microbiota and a number of other brain disorders has been reported. As the evidence so far for an association between the oral microbiota and ASDs rests on a few reports only, further studies in this field are necessary. The current review discusses a possible relationship between oral bacteria and the biologic and symptomologic aspects of ASD, focusing on the clinical implications for diagnostic and therapeutic development.

Exploring the Maternal and Infant Oral Microbiomes: A Pilot Study

Setting the stage for good oral health early in life is critical to long-term oral and overall health. This exploratory study aimed to characterize and compare maternal and newborn oral microbiota among mother-infant pairs. Oral samples were collected from 34 pregnant African American women and their infants at 1 to 3 months of age. Extracted 16SrRNA genes were matched to the Human Oral Microbiome Database. Alpha and beta diversity differed significantly between overall maternal and infant microbiomes. Maternal or infant alpha diversity, however, was not differentiated by maternal gingival status. Several demographic and behavioral variables were associated with, but not predictive of, maternal oral microbiome alpha diversity. There was no association, however, among birth mode, feeding mode, and the infant oral microbiome. Megasphaera micronuciformis was the only periodontal pathogen detected among the infants. Notably, maternal gingival status was not associated with the presence/absence of most periodontal pathogens. This study provides an initial description of the maternal and infant oral microbiomes, laying the groundwork for future studies. The perinatal period presents an important opportunity where perinatal nurses and providers can provide oral assessment, education, and referral to quality dental care.

A review of the influence of periodontal treatment in systemic diseases

The effects and consequences of periodontal diseases might not be confined to the oral cavity. A great body of evidence has arisen supporting the claim demonstrating an association with several systemic conditions and diseases. With different levels of evidence, an association between periodontal disease and cardiovascular disease, diabetes, psoriasis, rheumatoid arthritis, pregnancy outcomes and respiratory diseases has been established. However, the true nature of this association, if it is causal, still remains elusive. For a better understanding of the complex relationships linking different conditions, interventional studies now begin to focus on the possible outcomes of periodontal treatment in relation to the events, symptoms and biomarkers of several systemic disorders, assessing if periodontal treatment has any impact on them, hopefully reducing their severity or prevalence. Therefore, we proceeded to review the recent literature on the subject, attempting to present a brief explanation of the systemic condition or disease, what proposed mechanisms might give biological plausibility to its association with periodontal disease, and finally and more importantly, what data are currently available pertaining to the effects periodontal treatment may have. Raising awareness and discussing the possible benefits of periodontal treatment on overall systemic health is important, in order to change the perception that periodontal diseases are only limited to the oral cavity, and ultimately providing better and comprehensive care to patients.

Red complex periodontal pathogens are risk factors for liver cirrhosis

Periodontal disease has been associated with liver disease; however, the identities of the periodontal disease-causing bacteria in patients with viral liver disease remain unknown. The aim of the present study was to determine the counts of the 3 periodontal pathogens that form the red complex in chronic periodontitis (Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola) and 3 other bacteria (Aggregatibacter actinomycetemcomitans, Prevotella intermedia and Fusobacterium necrophorum) in patients with liver disease. A total of 47 patients with liver disease were divided into two groups based on the counts of the red complex bacteria: group A (high counts of red complex bacteria) and group B (low counts of red complex bacteria). The counts of the 6 types of bacteria in saliva and the prevalence of P. gingivalis-specific fimA genotype were determined. In addition, salivary occult blood tests and serological assays were performed. Univariate and multivariate logistic regression analyses were used to analyze the risk factors between the two groups of patients. Hepatitis C virus-related liver disease was the most frequent (41/47; 87.2%) occurrence followed by liver cirrhosis (LC; 12/47; 25.5%) and oral lichen planus (32/47; 68.1%). The significant risk factors between the two groups were LC, albumin (Alb) level, ratios of each bacteria and prevalence of the fimA II genotype. The 3 factors identified in the multivariate analysis to be associated with the red complex bacteria count were low Alb level (<3.7 g/dl), LC and fimA II genotype, with adjusted odds ratios of 6.93, 4.72 and 4.08, respectively (P<0.05). These data indicated that patients with LC were at increased risk of presenting with the red complex bacteria leading to periodontal disease progression. Therefore, these patients may need to take additional care of their oral health compared with patients without LC, which may prove beneficial for the maintenance of their general health.

Oral microbial biofilms: an update

Human oral cavity (mouth) hosts a complex microbiome consisting of bacteria, archaea, protozoa, fungi and viruses. These bacteria are responsible for two common diseases of the human mouth including periodontal (gum) and dental caries (tooth decay). Dental caries is caused by plaques, which are a community of microorganisms in biofilm format. Genetic and peripheral factors lead to variations in the oral microbiome. It has known that, in commensalism and coexistence between microorganisms and the host, homeostasis in the oral microbiome is preserved. Nonetheless, under some conditions, a parasitic relationship dominates the existing situation and the rise of cariogenic microorganisms results in dental caries. Utilizing advanced molecular biology techniques, new cariogenic microorganisms species have been discovered. The oral microbiome of each person is quite distinct. Consequently, commonly taken measures for disease prevention cannot be exactly the same for other individuals. The chance for developing tooth decay in individuals is dependent on factors such as immune system and oral microbiome which itself is affected by the environmental and genetic determinants. Early detection of dental caries, assessment of risk factors and designing personalized measure let dentists control the disease and obtain desired results. It is necessary for a dentist to consider dental caries as a result of a biological process to be targeted than treating the consequences of decay cavities. In this research, we critically review the literature and discuss the role of microbial biofilms in dental caries.

Effect of Dietary Fiber on the Composition of the Murine Dental Microbiome

The oral cavity houses a diverse consortium of microorganisms, heavily influenced by host diet, that can mediate dental health and disease. While the impact of dietary carbohydrates to the dental microbiome has been well-documented, the effect of fiber as a mechanical influence on the dental microbiome is unexplored. We performed 16S rRNA gene analysis to investigate the response of the dental microbiome to the presence of increased fiber in terms of microbial taxonomic abundance and diversity. Dental microbial community structure was significantly different in mice fed a diet supplemented with increased fiber and/or sugar. Fiber significantly affected measures of beta diversity at the phylum and genus levels, and a strong interactive effect on alpha diversity was observed between sugar and fiber at the phylum level. The addition of fiber also induced significant variation in relative taxonomic abundance. This study demonstrates that fiber can promote significant variations in the mouse dental microbiome.

The Gut Microbiota-Brain Axis Expands Neurologic Function: A Nervous Rapport

Does exploration of the gut microbiota-brain axis expand our understanding of what it means to be human? Recognition and conceptualization of a gut microbiota-brain axis challenges our study of the nervous system. Here, integrating gut microbiota-brain research into the metaorganism model is proposed. The metaorganism-an expanded, dynamic unit comprising the host and commensal organisms-asserts a radical blurring between man and microbe. The metaorganism nervous system interacts with the exterior world through microbial-colored lenses. Ongoing studies have reported that gut microbes contribute to brain function and pathologies, even shaping higher neurological functions. How will continued collaborative efforts (e.g., between neurobiology and microbiology), including partnerships with the arts (e.g., philosophy), contribute to the knowledge of microbe-to-mind interactions? While this is not a systemic review, this nascent field is briefly described, highlighting ongoing challenges and recommendations for emerging gut microbiota-brain research. Also see the video abstract here https://youtu.be/lP9gOW8StXg.

Clinical and Microbiological Effect of a Multispecies Probiotic Supplementation in Celiac Patients With Persistent IBS-type Symptoms: A Randomized, Double-Blind, Placebo-controlled, Multicenter Trial

GOALS

The goals of this study were to evaluate the efficacy and safety of a probiotic mixture in patients with celiac disease (CD) with irritable bowel syndrome (IBS)-type symptoms despite a strict gluten-free diet (GFD).

BACKGROUND

About 30% of patients with CD adherent to a GFD suffer from IBS-type symptoms; a possible cause resides in the imbalances of the intestinal microbiota in CD. Probiotics may represent a potential treatment.

STUDY

CD patients with IBS-type symptoms entered a prospective, double-blind, randomized placebo-controlled study. A 6-week treatment period was preceded by a 2-week run-in and followed by a 6-week follow-up phase. Clinical data were monitored throughout the study by validated questionnaires: IBS Severity Scoring System (IBS-SSS); Gastrointestinal Symptom Rating Scale (GSRS); Bristol Stool Form Scale (BSFS); and IBS Quality of Life Questionnaire (IBS-QOL). The fecal microbiota were assayed using plate counts and 16S rRNA gene-based analysis.

RESULTS

In total, 109 patients were randomized to probiotics (n=54) or placebo (n=55). IBS-SSS and GSRS decreased significantly in probiotics, as compared with placebo [(-15.9%±14.8% vs. 8.2%±25.9%; P<0.001) and (-19.8%±16.6% vs. 12.9%±31.6%; P<0.001)], respectively. Treatment success was significantly higher in patients receiving probiotics, as compared with placebo (15.3% vs. 3.8%; P<0.04). Presumptive lactic acid bacteria, Staphylococcus and Bifidobacterium, increased in patients receiving probiotic treatment. No adverse events were reported.

CONCLUSIONS

A 6-week probiotic treatment is effective in improving the severity of IBS-type symptoms, in CD patients on strict GFD, and is associated with a modification of gut microbiota, characterized by an increase of bifidobacteria.

Wine-Derived Phenolic Metabolites in the Digestive and Brain Function

Wine, and specifically red wine, is a beverage with a great chemical complexity comprising a particular combination of phenolic compounds which are directly associated with its health-promoting properties. Wine polyphenols could induce changes in the composition of intestinal microbiota that would affect the production of physiologically active phenolic metabolites modifying the content and phenolic profile at the systemic level. In addition, in the human population, it seems that different “metabotypes”, or patterns of metabolizing wine polyphenols, exist, which would be reflected in the different biological fluids (i.e., plasma, urine and feces) and tissues of the human body. Moreover, wine polyphenols might change the composition of oral microbiota by an antimicrobial action and/or by inhibition of the adhesion of pathogens to oral cells, thus contributing to the maintenance of oral health. In turn, polyphenols and/or its metabolites could have a direct action on brain function, by positively affecting signaling routes involved in stress-induced neuronal response, as well as by preventing neuroticism-like disorders (i.e., anxiety and depression) through anti-inflammatory and epigenetic mechanisms. All of this would condition the positive effects on health derived from moderate wine consumption. This paper reviews all these topics, which are directly related with the effects of wine polyphenols at both digestive and brain level. Further progresses expected in the coming years in these fields are also discussed.

Honey in oral health and care: A mini review

BACKGROUND

Honey is a natural product made from the nectar of flowers by honey bees and has over 200 compounds in it, including sugars, water, organic acids, minerals and polyphenols - the exact structure and composition of honey often determined by which plant source(s) the honey bee took the nectar from. Honey has been used in diets and medicines for thousands of years; however, this review, for the first time, aims to look at its place in modern medicine concerning oral health.

HIGHLIGHT

The present review for the first time attempted to address the protective effect of honey in the oral care.

CONCLUSION

For the first time this review addresses the usefulness of honey against Streptococcus mutans infections, dental plaque and caries, gingivitis and halitosis. Honey was also useful in preventing side effects associated with treatment of cancers of the head and neck, namely, radiation induced mucositis, xerostomia and poor wound healing. This is well supported by evidence in literature and was examined in this review.

In Vitro and In Vivo Activity of Peptidomimetic Compounds That Target the Periodontal Pathogen Porphyromonas gingivalis

The interaction of the periodontal pathogen Porphyromonas gingivalis with oral streptococci is important for initial colonization of the oral cavity by P. gingivalis and is mediated by a discrete motif of the streptococcal antigen I/II protein. A synthetic peptide encompassing this motif functions as a potent inhibitor of P. gingivalis adherence, but the use of peptides as topically applied therapeutic agents in the oral cavity has limitations arising from the relatively high cost of peptide synthesis and their susceptibility to degradation by proteases expressed by oral organisms. In this study, we demonstrate the in vitro and in vivo activity of five small-molecule mimetic compounds of the streptococcal peptide. Using a three-species biofilm model, all five compounds were shown to effectively inhibit the incorporation of P. gingivalis into in vitro biofilms and exhibited 50% inhibitory concentrations (IC₅₀s) of 10 to 20 μM. Four of the five compounds also significantly reduced maxillary alveolar bone resorption induced by P. gingivalis infection in a mouse model of periodontitis. All of the compounds were nontoxic toward a human telomerase immortalized gingival keratinocyte cell line. Three compounds exhibited slight toxicity against the murine macrophage J774A.1 cell line at the highest concentration tested. Compound PCP-III-201 was nontoxic to both cell lines and the most potent inhibitor of P. gingivalis virulence and thus may represent a novel potential therapeutic agent that targets P. gingivalis by preventing its colonization of the oral cavity.

Smokeless tobacco impacts oral microbiota in a Syrian Golden hamster cheek pouch carcinogenesis model

The use of smokeless tobacco products (STPs) can cause many serious health problems. The oral microbiota plays important roles in oral and systemic health, and the disruption in the oral microbial population is linked to periodontal disease and other health problems. To assess the impact of smokeless tobacco on oral microbiota in vivo, high-throughput sequencing was used to examine the oral microbiota present in Syrian Golden hamster cheek pouches. Sixteen hamsters were divided into four groups and treated with the STP Grizzly snuff (0, 2.5, 25, or 250 mg) twice daily for 4 weeks. After 0, 1, 2, 3, and 4 weeks of treatment, bacterial genomic DNA was extracted from oral swabs sampled from the cheek pouches of the hamsters. The oral bacterial communities present in different hamster groups were characterized by sequencing the hypervariable regions V1-V2 and V4 of 16S rRNA using the Illumina MiSeq platform. Fifteen phyla, 27 classes, 59 orders, 123 families, and 250 genera were identified from 4,962,673 sequence reads from the cheek pouch samples. The bacterial diversity and taxonomic abundances for the different treatment groups were compared to the non-treated hamsters. Bacterial diversity was significantly decreased after 4 weeks of exposure to 2.5 mg, and significantly increased by exposure to 250 mg STP. Treatment with 250 mg STP significantly increased Firmicutes, transiently increased Cyanobacteria and TM7, and decreased Bacteroidetes and Fusobacteria compared to the control group. At the genus level, 4 weeks of administration of 250 mg STP significantly increased Granulicatella, Streptococcus, Oribacterium, Anaerococcus, Acidaminococcus, Actinomyces, Eubacterium, Negativicoccus, and Staphylococcus, and decreased Bacteroides, Buleidia, Dialister, and Leptotrichia, and transiently decreased Arcanobacterium compared to the control group. For the first time, an animal model was used for evaluating the effects of STP on oral microbiota by metagenomic sequencing. Our results provide a view of the shift of the oral microbiota in response to STP exposure in Syrian Golden hamster. Our findings indicate that the use of smokeless tobacco significantly disrupts the oral microbiota.

Feasibility of Providing Safe Mouth Care and Collecting Oral and Fecal Microbiome Samples from Nursing Home Residents with Dysphagia: Proof of Concept Study

Individuals with dysphagia who reside in nursing homes often receive inadequate mouth care and experience poor oral health. From a policy perspective, the combination of absent evidence-based mouth care protocols coupled with insufficient dental coverage create a pool of individuals at great risk for preventable infectious illnesses that contribute to high health care costs. The purpose of the current study was to determine (a) the safety of a mouth care protocol tailored for individuals with dysphagia residing in nursing homes without access to suction equipment, and (b) the feasibility of collecting oral and fecal samples for microbiota analyses. The mouth care protocol resulted in improved oral hygiene without aspiration, and oral and fecal samples were safely collected from participants. Policies supporting ongoing testing of evidence-based mouth care protocols for individuals with dysphagia are important to improve quality, demonstrate efficacy, and save health care costs. [Journal of Gerontological Nursing, 43(9), 9-15.].

Oral microbiome and health

The oral microbiome is diverse in its composition due to continuous contact of oral cavity with the external environment. Temperatures, diet, pH, feeding habits are important factors that contribute in the establishment of oral microbiome. Both culture dependent and culture independent approaches have been employed in the analysis of oral microbiome. Gene-based methods like PCR amplification techniques, random amplicon cloning, PCR-RELP, T-RELP, DGGE and DNA microarray analysis have been applied to increase oral microbiome related knowledge. Studies revealed that microbes from the phyla Firmicutes, Proteobacteria, Bacteroidetes, Actinobacteria, Fusobacteria, Neisseria, TM7 predominately inhabits the oral cavity. Culture-independent molecular techniques revealed the presence of genera Megasphaera, Parvimonas and Desulfobulbus in periodontal disease. Bacteria, fungi and protozoa colonize themselves on various surfaces in oral cavity. Microbial biofilms are formed on the buccal mucosa, dorsum of the tongue, tooth surfaces and gingival sulcus. Various studies demonstrate relationship between unbalanced microflora and development of diseases like tooth caries, periodontal diseases, type 2 diabetes, circulatory system related diseases etc. Transcriptome-based remodelling of microbial metabolism in health and disease associated states has been well reported. Human diets and habitat can trigger virus activation and influence phage members of oral microbiome. As it is said, “Mouth, is the gateway to the total body wellness, thus oral microbiome influences overall health of an individual”.

Probiotics: A Promising Role in Dental Health

Probiotics have a role in maintaining oral health through interaction with oral microbiome, thus contributing to healthy microbial equilibrium. The nature and composition of any individual microbiome impacts the general health, being a major contributor to oral health. The emergence of drug resistance and the side effects of available antimicrobials have restricted their use in an array of prophylactic options. Indeed, some new strategies to prevent oral diseases are based on manipulating oral microbiota, which is provided by probiotics. Currently, no sufficient substantial evidence exists to support the use of probiotics to prevent, treat or manage oral cavity diseases. At present, probiotic use did not cause adverse effects or increased risks of caries or periodontal diseases. This implicates no strong evidence against treatment using probiotics. In this review, we try to explore the use of probiotics in prevention, treatment and management of some oral cavity diseases and the possibilities of developing designer probiotics for the next generation of oral and throat complimentary healthcare.

Mechanical Ventilation and Cytopathological Changes in the Oral Mucosa

BACKGROUND

The oral mucosa is an important defense barrier to penetration of microorganisms. Thus, changes in the oral epithelium might indicate risk for infection in intensive care patients receiving mechanical ventilation.

OBJECTIVE

To evaluate the oral mucosa of intensive care patients who did or did not receive mechanical ventilation by using liquid-base exfoliative cytology.

METHODS

The sample consisted of 3 groups: 27 patients admitted to intensive care during a 7- to 14-day period who received mechanical ventilation, 29 patients admitted during the same period who did not receive mechanical ventilation, and 27 healthy patients who had no lesions in the mouth. For all 3 groups, samples were collected from the buccal mucosa by using cytology brushes. Smears were applied to glass slides before Papanicolaou staining and were codified for blind analyses by a cytopathologist. Kruskal-Wallis and Dunn tests were used to analyze the results.

RESULTS

Patients receiving mechanical ventilation had higher prevalence and intensity of karyomegaly, perinuclear halos, cell keratinization, deep cells, and leukocyte infiltrates than did patients in the other 2 groups (P < .05). No significant differences were observed between the control group and the group who did not receive mechanical ventilation.

CONCLUSIONS

Liquid-base exfoliative cytology can be used to detect preclinical alterations in the oral mucosa. Patients treated with mechanical ventilation are vulnerable to infections, and oral care may be valuable in their prognosis.