"It's really no more difficult than putting on fluoride varnish":a qualitative exploration of dental professionals' views of silver diamine fluoride for the management of carious lesions in children

Background Despite evidence that Silver Diamine Fluoride (SDF) can be effective in managing carious lesions in primary teeth, the use of SDF in the UK remains limited. This study explored dental professionals’ views and experiences of using SDF for managing carious lesions in children. In addition, it explored what they perceived to be the advantages, disadvantages, barriers and enablers to the use of SDF in practice. Methods Fifteen semi-structured face-to-face or over-the-phone interviews were conducted with 14 dental professionals from NHS Tayside and NHS Grampian in Scotland. Interviews were transcribed verbatim, coded and analysed using a thematic approach. Results Thirteen of 14 dental professionals interviewed were familiar with, or had some existing knowledge of, SDF. Four had used it to treat patients. The majority of participants thought that the main advantage of SDF was that it required minimal patient cooperation. SDF was also perceived as a simple, pain-free and non-invasive treatment approach that could help acclimatise children to the dental environment. However, SDF-induced black staining of arrested carious lesions was most commonly reported as the main disadvantage and greatest barrier to using it in practice. Participants believed that this discolouration would concern some parents who may fear that the black appearance may instigate bullying at school and that others may judge parents as neglecting their child’s oral health. Participants thought that education of clinicians about SDF use and information sheets for parents would enhance the uptake of SDF in dental practice. Participants believed that younger children might not be as bothered by the discolouration as older ones and they anticipated greater acceptance of SDF for posterior primary teeth by both parents and children. Conclusion Dental professionals were aware that SDF can be used for arresting carious lesions. They pointed out that the staining effect of carious lesions is a major disadvantage that could be a barrier for many parents. Participants considered the application process to be simple and non-invasive and requires a minimum level of child cooperation. Participants appreciated the potential of SDF in paediatric dentistry and suggested actions that could help overcome the barriers they highlighted

Silver compounds used in dentistry for caries management: a review

OBJECTIVE: Silver compounds have been used for their medical properties for centuries and in dentistry for more than a century. The aim of this review is to examine the evidence supporting the therapeutic use of silver in dentistry and the outcomes from the clinical trials, as well as mode of action and biocompatibility. DATA SOURCES: Literature was searched using the PubMed database between the year 1966 and 2011, with principle key terms such as 'Silver Nitrate', 'Silver Fluoride', 'Silver Diammine Fluoride', 'Silver compounds' and 'Dental caries'. Hand searching was performed for relevant papers cited in the indices back to the year 1905. RESULTS: In vitro, in vivo and clinical evidence have demonstrated that silver compounds are viable agents for preventing and arresting caries both in the primary and permanent dentition; however they are associated with adverse tooth discolouration and some reports that pulp irritation may occur. Further research has investigated its effectiveness as a dentine desensitiser, root canal disinfectant and even in silver impregnated restorative materials. The mode of action of silver compounds on carious tooth tissues is thought to include inhibition of the demineralization process, as well as an anti-bacterial effect by interference of bacterial cell membranes, cytoplasmic enzymes and inhibition of bacterial DNA replication. CONCLUSION: Silver compounds have been shown to be an effective anti-caries agent; however, there is an incomplete understanding of how silver compounds prevent caries. Further research is required to help identify its most efficacious use and limitations.link_to_subscribed_fulltex

Inhibition of HBV replication and gene expression in vitro and in vivo with a single AAV vector delivering two shRNA molecules

Hepatitis B virus (HBV) infection is highly prevalent worldwide. The major challenge for current antiviral treatment is the elevated drug resistance that occurs via rapid viral mutagenesis. In this study, we developed AAV vectors to simultaneously deliver two or three shRNAs targeting different HBV-related genes. These vectors showed markedly better antiviral effects than ones that delivered a single shRNA in vitro. A dual shRNA expression vector (AAV-157i/1694i), which simultaneously expressed two shRNAs targeted the S and X genes of HBV, reduced HBsAg, HBeAg and HBV DNA levels by 87±4, 80.3±2.6 and 86.2±7% respectively, eight days post-transduction. In a mouse model of prophylactic treatment, HBsAg and HBeAg were reduced to undetectable levels and the serum HBV DNA level was reduced by at least 100 fold. These results indicate that AAV-157i/1694i generates potent anti-HBV effects and that the strategy of constructing multi-shRNA expression vectors may lead to enhanced anti-HBV efficacy and overcome the evading mechanism of the virus and thus the development of drug resistance.link_to_OA_fulltex