Effect of audiovisual distraction on the management of dental anxiety in children: A systematic review.

BACKGROUND: Audiovisual distraction, a non-pharmacological intervention, has been used to manage dental anxiety in prior clinical trials. AIM: Synthesize the available evidences to evaluate the efficacy of audiovisual distraction techniques on the management of dental anxiety in children. DESIGN: Electronic databases (PubMed, Cochrane Central Register of Controlled Trials, and Embase) were searched. We included randomized controlled trials (RCTs), and methodological quality of included trials was assessed using the Cochrane Collaboration's criteria. Information on reported anxiety, pain, behaviors, vital signs (including blood pressure, oxygen saturation, and pulse rate), and children satisfaction was analyzed. RESULTS: Nine studies were included for a systematic review, and none of them had low risk of bias. Significant differences in anxiety were found. According to the study, a majority of results indicated a significant difference in pain and behavior between the audiovisual and control group. Three studies reported children in the audiovisual group preferred usage of an audiovisual device for future dental visits. No significant differences could be found regarding blood pressure. CONCLUSIONS: There is some low-quality evidence suggesting that the usage of audiovisual distraction during dental treatment may relieve children's dental anxiety.

Measuring the attitudes of dental students towards social accountability following dental education - Qualitative findings.

BACKGROUND: The term social accountability has gained increased interest in medical education, but is relatively unexplored in dentistry. AIMS: The aim of this study is to explore dental students' attitudes towards social accountability. METHODS: A qualitative study utilizing focus groups with University of Otago final year (5th year) Bachelor of Dental Surgery (BDS) students was carried out. A questionnaire designed to measure medical students' attitudes towards social responsibility was used as a guide. Following data collection, framework analysis was used to analyze each of the three focus groups, and repeating themes were noted. RESULTS: Analysis of the focus groups discovered recurring themes, such that participants believed that dentists should be accountable to society in a professional context and that they are responsible for patients who present at their clinic but that there is no professional obligation to help reduce oral health inequalities by working with populations facing inequalities. There was strong agreement that there needs to be change to the dental health care system from a structural and political level to address oral health inequalities, rather than individual dentists assuming greater responsibility. CONCLUSION: Our findings show that dental education may not be accountable to society in the sense that it is not producing graduates who believe that they have an obligation to address the priority oral health concerns of society.

Candida albicans promotes tooth decay by inducing oral microbial dysbiosis.

Candida albicans has been detected in root carious lesions. The current study aimed to explore the action of this fungal species on the microbial ecology and the pathogenesis of root caries. Here, by analyzing C. albicans in supragingival dental plaque collected from root carious lesions and sound root surfaces of root-caries subjects as well as caries-free individuals, we observed significantly increased colonization of C. albicans in root carious lesions. Further in vitro and animal studies showed that C. albicans colonization increased the cariogenicity of oral biofilm by altering its microbial ecology, leading to a polymicrobial biofilm with enhanced acidogenicity, and consequently exacerbated tooth demineralization and carious lesion severity. More importantly, we demonstrated that the cariogenicity-promoting activity of C. albicans was dependent on PHR2. Deletion of PHR2 restored microbial equilibrium and led to a less cariogenic biofilm as demonstrated by in vitro artificial caries model or in vivo root-caries rat model. Our data indicate the critical role of C. albicans infection in the occurrence of root caries. PHR2 is the major factor that determines the ecological impact and caries-promoting activity of C. albicans in a mixed microbial consortium.

Novel Approaches to the Control of Oral Microbial Biofilms.

Effective management of biofilm-related oral infectious diseases is a global challenge. Oral biofilm presents increased resistance to antimicrobial agents and elevated virulence compared with planktonic bacteria. Antimicrobial agents, such as chlorhexidine, have proven effective in the disruption/inhibition of oral biofilm. However, the challenge of precisely and continuously eliminating the specific pathogens without disturbing the microbial ecology still exists, which is a major factor in determining the virulence of a multispecies microbial consortium and the consequent development of oral infectious diseases. Therefore, several novel approaches are being developed to inhibit biofilm virulence without necessarily inducing microbial dysbiosis of the oral cavity. Nanoparticles, such as pH-responsive enzyme-mimic nanoparticles, have been developed to specifically target the acidic niches within the oral biofilm where tooth demineralization readily occurs, in effect controlling dental caries. Quaternary ammonium salts (QAS) such as dimethylaminododecyl methacrylate (DMADDM), when incorporated into dental adhesives or resin composite, have also shown excellent and durable antimicrobial activity and thus could effectively inhibit the occurrence of secondary caries. In addition, custom-designed small molecules, natural products and their derivatives, as well as basic amino acids such as arginine, have demonstrated ecological effects by modulating the virulence of the oral biofilm without universally killing the commensal bacteria, indicating a promising approach to the management of oral infectious diseases such as dental caries and periodontal diseases. This article aims to introduce these novel approaches that have shown potential in the control of oral biofilm. These methods may be utilized in the near future to effectively promote the clinical management of oral infectious diseases and thus benefit oral health.

Function of alanine racemase in the physiological activity and cariogenicity of Streptococcus mutans.

The enzyme alanine racemase (Alr) has been a new target for the development of antibacterial drugs based on the involvement of D-Ala in bacterial cell wall biosynthesis. Our previous study noted that Alr is essential for the growth and interspecies competitiveness of S. mutans, the major causative organism of dental caries. However, physiological activity and cariogenicity of S. mutans affected by Alr remains unknown. The current study examined the biofilm biomass, biofilm structure, extracellular polysaccharide (EPS) synthesis, glucosyltransferase (gtf) gene expression, acid production and acid tolerance in the alr-mutant strain. We found that biofilm formation, biofilm structure, and EPS synthesis was in a D-Ala dose-dependent manner. Biofilm structure was loose in alr-mutant group and the ratio of EPS/bacteria was also elevated. Additionally, the expression levels of multiple gtfs were up-regulated, and acid tolerance was decreased. We also established in vivo models of dental caries and found that the incidence and severity of the caries were decreased in the alr-mutant group in comparison to the parental S. mutans group. Our in vivo and in vitro experiments demonstrate that Alr is essential for the cariogenicity of S. mutans and that Alr might be a potential target for the prevention and treatment of caries.

Investigation of recombinant human elastin polypeptides as non-thrombogenic coatings.

We investigated the use of a recombinant human elastin polypeptide as a coating on synthetic materials with a view to determining if these polypeptides could improve the blood compatibility of cardiovascular devices such as vascular conduits and arterial/venous catheters. Platelet adhesion and activation were studied in vitro using three commercially available synthetic materials: polyethylene terephthalate (Mylar), a poly(tetrafluoroethylene/ethylene) copolymer (Tefzel) and a polycarbonate polyurethane (Corethane). Coated with adsorbed polypeptide, all three synthetic materials demonstrated reduced platelet activation and adhesion in platelet rich plasma in vitro. Compared to non-coated controls, there was a significant decrease (p=0.05) in both platelet microparticle release and P-selectin expression for the polypeptide-coated surfaces. Scanning electron microscopy indicated fewer adhering platelets on coated surfaces compared to non-coated controls. In vivo, in a rabbit model, evaluations of polyurethane catheters coated with the polypeptide showed a marked increase in catheter patency and a significant decrease in fibrin accretion and embolism when compared to uncoated controls. This polypeptide shows a strong potential for use as a non-thrombogenic coating for small diameter vascular grafts. In addition, the results of this study indicate that the elastin polypeptide would be a valuable component of a tissue engineered vascular conduit.