Aim: The purpose of this study was to compare disinfection of deciduous root canal by conventional chemomechanical debridement (CMD) with sodium hypochlorite (0.5%) vs laserassisted photodynamic therapy (PDT). Materials and methods:Twelve children aged 4 to 7 years with informed consent from their parents were studied. Access cavities were prepared and culture samples were taken before the commencement of the therapy, after CMD using 0.5% sodium hypochlorite and after laser-assisted PDT using methylene blue (MB) dye. Samples were taken by placing a sterile paper cone into the canals and transferring them into brain heart infusion broth. The samples were then subjected for microbiological processing so as to count the total number of viable bacteria.Results: Laser-treated canals showed a reduction in bacterial load by 99.99% as against 83.9% obtained after the use of conventional CMD with sodium hypochlorite. Conclusion:Laser-assisted PDT can be used as an excellent adjunct to CMD to obtain near perfect disinfection of deciduous root canals.

Aim: To determine the enamel solubility and depth of demineralization with laser bleaching and impact of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) when applied prior to and after laser bleaching. Materials and methods:The 40 specimens obtained from 10 human premolars were treated in accordance with manufacturer protocols; laser bleaching was performed using Opalescence Boost Gel (40% hydrogen peroxide) followed by laser activation using 36 mW/660 nm diode laser applied for 4 minutes at an energy fluence of 8.6 J/cm 2 . The study consisted of four experimental groups are as follows: Specimens were, thereafter, subjected to cariogenic challenge and further evaluated for enamel solubility by measuring the loss of Ca 2+ ions and the depth of demineralization using polarized light microscopy.Results: Group 4 exhibited least enamel solubility and depth of demineralization (p < 0.0001) followed by groups 3, 2 and maximum by group 1. Conclusion:Post-laser bleaching application of CPP-ACP followed by a short burst of laser can provide exceptional resistance to enamel solubility (demineralization).