Candida spp. adherence to oral epithelial cells and levels of IgA in children with orthodontic appliances

Association Between Oral Behaviors and Painful Temporomandibular Disorders: A Cross-Sectional Study in the General Population

Background

Studies have reported correlations between various oral behaviors and painful temporomandibular disorders (TMD), yet comprehensive research on the independent effects of each oral behavior within the general population remains sparse.

Objective

This cross-sectional study aimed to investigate the association between painful TMD (PT) and various oral behaviors in general population.

Methods

A questionnaire survey was conducted with participants to collect data encompassing demographic characteristics, eight specific oral behaviors, and the 5 major TMD symptoms(5Ts) checklist. Participants were categorized into PT and non-PT (NPT) groups based on their responses to the 5Ts checklist. Those reporting TMJ/facial pain or headaches were assigned to the PT group, while all other participants constituted the NPT group. Both univariate and multivariate logistic regression analyses were employed to evaluate the association between individual oral behavior and the presence of PT, controlling for demographic confounders including age, sex, systemic diseases, and dental treatments history.

Results

A total of 441 valid questionnaires were received, including 156 males and 285 females. The prevalence of PT was identified to be 33.33%, with 61.00% of participants engaging in one or more types of oral behaviors. Each oral behavior was more frequently reported in the PT group compared to the NPT group. The univariate logistic regression analysis identified positive correlations between all eight oral behaviors and PT. In the multivariate logistic regression analysis, these associations persisted after adjustment for demographic confounders including age, sex, history of systemic diseases and dental treatments (P<0.01). The behaviors most strongly associated with PT were "Hold or jut jaw forward/to the side" (OR:4.478), "Hold, tighten or tense muscles without clench" (OR:3.343) and "Hold jaw in rigid or tense position" (OR:3.209).

Conclusion

The presence of oral behaviors has significant association with PT. Individuals exhibiting multiple oral behaviors are more likely to experience PT. Additional studies are needed to clarify the effects of reducing oral behaviors on pain-related symptoms.

The Effect of Removable Orthodontic Appliances on Oral Microbiota: A Systematic Review

Background (1): Removable orthodontic appliances may favor plaque accumulation and oral microbe colonization. This might be associated with intraoral adverse effects on enamel or periodontal tissues. The proposed systematic review was carried out to evaluate qualitatively and quantitatively the microbiological changes occurring during orthodontic therapy with removable orthodontic appliances. Methods (2): PubMed, Cochrane Library, Embase, Web of Science, Scopus, Ovid Medline, and Dentistry and Oral Sciences Source were searched. The research included every article published up to January 2020. The Preferred Reporting Items for Reporting Systematic reviews and Meta Analyses (PRISMA) protocol and the “Swedish Council on Technology Assessment in Health Care Criteria for Grading Assessed Studies” (SBU) method were adopted to conduct this systematic review. Results (3): The current study has a moderate evidence, demonstrating that removable appliances do influence the oral microbiota. Significant alterations occur just 15 days after the beginning of therapy, independently from the type of appliance. Furthermore, the levels of oral pathogens decrease significantly or even returned to pre-treatment levels several months later the therapy end. Conclusions (4): This review suggests that orthodontic treatment with removable appliances induces changes to oral microflora, but these alterations might not be permanent.

Mediation of Mucosal Immunoglobulins in Buccal Cavity of Teleost in Antibacterial Immunity

The buccal mucosa (BM) of vertebrates is a critical mucosal barrier constantly exposed to rich and diverse pathogens from air, water, and food. While mammals are known to contain a mucosal associated lymphoid tissue (MALT) in the buccal cavity which induces B-cells and immunoglobulins (Igs) responses against bacterial pathogens, however, very little is known about the evolutionary roles of buccal MALT in immune defense. Here we developed a bath infection model that rainbow trout experimentally exposed to Flavobacterium columnare (F. columnare), which is well known as a mucosal pathogen. Using this model, we provided the first evidence for the process of bacterial invasion in the fish BM. Moreover, strong pathogen-specific IgT responses and accumulation of IgT⁺ B-cells were induced in the buccal mucus and BM of infected trout with F. columnare. In contrast, specific IgM responses were for the most part detected in the fish serum. More specifically, we showed that the local proliferation of IgT⁺ B-cells and production of pathogen-specific IgT within the BM upon bacterial infection. Overall, our findings represent the first demonstration that IgT is the main Ig isotype specialized for buccal immune responses against bacterial infection in a non-tetrapod species.

Uptake of clinical yeast isolates by human epithelial cell line

OBJECTIVE

The occurrence of yeast infections in humans has increased, with the species belonging to genus Candida still being the most common cause of infection. Nevertheless, infections caused by less common yeasts have been widely reported in recent years. The main objective of this study was to assess the potential of these less common saprophytic yeasts to invade the host cell, which is essential for causing systemic infections.

MATERIAL AND METHODS

Various yeast isolates were identified by DNA sequence information of PCR amplified ITS region. The purported saprophytic yeasts were characterized for internalization by mammalian cells in vitro, by staining the F-actin.

CONCLUSION

The identification of different yeast isolates from various patients revealed that 70% of the isolates belonged to the genus Candida, while remaining 30% of the isolates were yeasts not belonging to genus Candida. These non-Candida clinical isolates, either in yeast or hyphal forms, were efficiently internalized by human epithelial cells. The internalization was marked by a process of actin polymerization surrounding the invading yeast. Such uptake by epithelial cells signifies traversal of cell barrier by yeast cells during infection in vivo.