Phenotypic switch: The enigmatic white-gray-opaque transition system of Candida albicans.

Candida albicans represents the most common commensal and opportunistic fungal pathogen colonizing humans. As a member of the normal microflora, it is present on the skin and the mucous membranes of the upper respiratory tract, gastrointestinal tract and female genital tracts. It is therefore not transmitted. It lies in wait for a change in some aspect of the host physiology that normally suppress growth and invasiveness through an enigmatic phenomenon called Phenotypic Switch System or White-Opaque Transition. This system involves reversible and heritable switching between alternative cellular phenotypes. White-opaque switching in Candida albicans was first discovered in 1987. This was initially identified in strain WO-1. Switching has been demonstrated to occur at sites of infection and to occur between recurrent episodes of infection in select cases esp. AIDS and diabetes.

Prions in dentistry: A need to be concerned and known.

Prion diseases were first discovered by Stanley B. Prusiner who defined prions as infectious, transmissible proteinaceous particles that lack nucleic acid and are composed exclusively of a modified isoform of the noninfectious cellular prion protein (PrPC). These are incurable neurodegenerative conditions affecting both animals and humans. They may be sporadic, infectious or inherited in origin. Human prion diseases include Creutzfeldt-Jakob desease (CJD), Gerstmann- Straussler-Scheinker disease, Kuru and Fatal familial insomnia. Prions resist the conventional sterilization procedures and hence the dentists must be aware of such diseases so as to opt standard methods of infection control and decontamination for such infectious agents. This review article divulge the dentists with a brief overview of the characteristics of prions, the risk of transmission and the implications for infection control in dentist.

Prevalence of malocclusion among 12 to 15 years age group orphan children using dental aesthetic index.

OBJECTIVE: The study was done to determine the prevalence of malocclusion and orthodontic treatment among orphan children. MATERIALS AND METHODS: The sample consisted of 165 orphan children aged between 12 and 15 years. A clinical examination was used to determine the orthodontic treatment need according to the Dental Aesthetic Index (DAI). The statistical software namely SPSS version 15.0 was used for the analysis different parameters as gender and age. RESULTS: The prevalence of definite, severe and very severe malocclusion was more among males than females and it increased with age. 16.4% subjects needed orthodontic treatment ranging from slight to mandatory form. CLINICAL SIGNIFICANCE: The prevalence and severity of malocclusion was more among orphan children as they are deprived of healthy lifestyle. So, they should be identified and corrective measures instituted at the earliest to prevent a widespread impact on their psychological development.

Effect of three different core materials on the fracture resistance of endodontically treated deciduous mandibular second molars: an in vitro study.

Endodontic treatment makes the tooth brittle due to loss of bulk of tooth structure, decrease in the moisture content of dentin and dentin elasticity. The following study was carried out to evaluate the effect of endodontic treatment on the fracture resistance of the tooth and reinforcing ability of three different core materials. The following study comprised of sample size of 30 deciduous second molars divided into control group (6) and test group (24). Access opening was done in 24 and 18th teeth with access opening were restored with three different core materials namely IRM (6), silver amalgam (6), GIC (6). All the 30 were subjected to fracture test using UTM (Universal testing machine)- Instron 95. Result showed a drastic reduction in the fracture resistance of the tooth on access opening (1/3rd) and out of the three core materials glass ionomer was shown to be the best core material giving the highest fracture registrance followed by silver amalgam and IRM.

Caries prevention effect of intensive application of sodium fluoride varnish in molars in children between age 6 and 7 years.

BACKGROUND: The aim of this study was to evaluate the efficacy of intensive application of sodium fluoride varnish in prevention of caries in molars in children between 6 and 7 years and to evaluate the caries status in molars before and after application of fluoride varnish (Cavity Shield). MATERIALS AND METHODS: Two hundred fifty children (6-7 years) randomized into varnish and control groups. Children in varnish group received fluoride varnish (Cavity Shield) three times during one week (once every 2 days). Clinical and radiographical examinations of all children were performed prior to the first application of varnish and 1 year later. For evaluation and comparison, all the collected data were subjected to statistical analysis. RESULTS: At the end of 1 year period, varnish group had 27.7% caries reversal in deciduous dentition which was statistically significant. Though there was a decrease in the caries increment in the permanent dentition, it was not statistically significant. CONCLUSION: Application of fluoride varnish Cavity Shield three times once a week, once a year either in permanent or in deciduous dentition, is associated with substantial reduction in caries increment. CLINICAL SIGNIFICANCE: Fluoride varnish can prove to be an effective tool in prevention of dental caries in both primary and permanent dentitions.