The aim of this in vitro study was to evaluate the effect of erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser pretreatment alone, or associated with acid etching, on the quality of marginal integrity (microleakage and marginal gap) of a resin-based fissure sealant in primary teeth. Fifty sound primary molar teeth were randomly assigned to one of five study groups, pretreated as follows: (1) 35% orthophosphoric acid etching; (2) 2.5 W laser etching; (3) 3.5 W laser etching; (4) 2.5 W laser + 35% orthophosphoric acid etching; (5) 3.5 W laser + 35% orthophosphoric acid etching. After surface pretreatment, a resin-based sealant (ClinPro) was applied to the fissures. Sample teeth were then subjected to thermocycling and stored thereafter in distilled water at 37 degrees C for 1 month. Following immersion in 0.5% basic fuchsin solution for 24 h, three bucco-lingual slices of each sample tooth were scored under a stereo-microscope. Statistical analysis was performed with Kruskal-Wallis one-way analysis of variance (ANOVA) and Pearson chi-square tests. The level of significance was set at P < 0.05. Microleakage scores of group 1 were significantly less than those of groups 2 and 3 (P < 0.05), whereas no statistically significant difference was observed between groups 1, 4 and 5 (P > 0.05). In terms of marginal gap formation, no significant difference was observed between groups (P > 0.05). It was concluded that Er,Cr:YSGG laser etching did not eliminate the need for acid etching. When combined with acid etching, Er,Cr:YSGG laser seems to be as effective as conventional acid etching.

The objective of this study was to compare the antimicrobial activity of sodium hypochlorite (NaOCl), chlorhexidine gluconate (CHX) and octenidine hydrochloride (OCT) in different concentrations against endodontic pathogens in vitro. Agar diffusion procedure was used to determine the antimicrobial activity of the tested materials. Enterococcus faecalis, Candida albicans and the mixture of these were used for this study. In the agar diffusion test, 5.25% NaOCl exhibited better antimicrobial effect than the other concentrations of NaOCl for all strains. All concentrations of OCT were effective against C. albicans and E. faecalis. Some 0.2% CHX was ineffective on all microorganisms. Antibacterial effectiveness of all experimental solutions decreased on the mixture of all strains. Decreasing concentrations of NaOCl resulted in significantly reduced antimicrobial effect.

The World Health Organization (2011) recently estimated that 285 million people are visually impaired worldwide: 39 million are blind and 246 million have low vision. In Turkey, the results of the disability statistics calculated by the Turkish Statistical Institute (2002) revealed that 12.29% of the total population was disabled and 0.60% of these people were visually impaired.