Background: one of the complications of power bleaching is surface roughness of enamel which increases the possibility of post bleaching teeth discoloration. The aim of the present study is to evaluate the effect of toothpaste containing nano hydroxyapatite, NovaMin and kin sense fluoride on surface roughness of human tooth enamel after laser bleaching with 35% hydrogen peroxide bleaching gel. Materials and Methods: Twenty human enamel incisors were cleaned and their labial surface polished up to #1200, then categorized into four equal groups; first group kept without bleaching as a control group, while the remaining three experimental groups were bleached with 35% hydrogen peroxide, and each group treated with a restore paste containing o

Abstract:

Aim: The goal of this research was to study the influence of Er,Cr:YSGG laser at short pulse duration (60 µsec) on the number of streptococcus mutans bacteria in vitro.

Material and Methods:  twenty-eight extracted third molars free of caries, cracks, and other irregularities were used. For the testing of the materials, both the agar well technique and a tooth cavity model were employed. The agar wells of plates that had been inoculated with Streptococcus mutans previously were stuffed with the test materials, in order to conduct the tests. The zones of inhibition were assessed using millimeter measurements, after an incubation period of 48 hours .In order to a

 Abstract Objective: Comparison of femtosecond small incision lenticule extraction (FS-SMILE) versus Femtosecond laser Insitu keratomileusis (FS-LASIK) regarding dry eye disease (DED) and corneal sensitivity (CS) after those refractive surgeries. Methods: A comparative prospective study conducted for a period of 2 years; from March 2017 until February, 2019. Enrolled patients were diagnosed with myopia. Fifty patients (100 eyes) were scheduled for bilateral FS-SMILE and the other 50 patients (100 eyes) had been scheduled for bilateral FS-LASIK. Both groups were followed for six months after surgery. The age, gender, and preoperative refraction for both groups were matched. Complete evaluation of dry eye disease had been

 Abstract Objective: Comparison of femtosecond small incision lenticule extraction (FS-SMILE) versus Femtosecond laser Insitu keratomileusis (FS-LASIK) regarding dry eye disease (DED) and corneal sensitivity (CS) after those refractive surgeries. Methods: A comparative prospective study conducted for a period of 2 years; from March 2017 until February, 2019. Enrolled patients were diagnosed with myopia. Fifty patients (100 eyes) were scheduled for bilateral FS-SMILE and the other 50 patients (100 eyes) had been scheduled for bilateral FS-LASIK. Both groups were followed for six months after surgery. The age, gender, and preoperative refraction for both groups were matched. Complete evaluation of dry eye disease had been

Abstract: The power and the size of the final spot of the laser beam reaching the target are very important requirements in most of the laser applications and fields such as medical, military, and scientific, so studying laser propagation in the atmosphere is a very important topic. The propagation of the laser beam through the atmosphere is subject to several attenuation processes that deplete the power and expand the beam. Through the simulation results of the free electron laser within the visible region of the electromagnetic spectrum (400-700nm), it was found that the attenuation increases with decreasing wavelength. Laser propagation in the presence of rain and snow leads to a very large loss of power compared to propagation i

The increase globally fossil fuel consumption as it represents the main source of energy around the world, and the sources of heavy oil more than light, different techniques were used to reduce the viscosity and increase mobility of heavy crude oil. this study focusing on the experimental tests  and modeling with Back Feed Forward Artificial Neural Network (BFF-ANN) of the dilution technique to reduce a  heavy oil viscosity that was collected from the south- Iraq oil fields using organic solvents, organic diluents with different weight percentage  (5, 10 and  20 wt.% )  of  (n-heptane, toluene, and a mixture of  different ratio

Cerebellum is the most important and critical part of the central nervous system, cerebellum is very sensitive to the abnormal changes during the embryological development in its histological structure, the exposure to any infection during embryogenesis produce abnormalities in the cerebellum and behavioral of offspring. In this study we tried to study the ontogenesis of the cerebellum in the embryos of the albino rats and detection the effect of the AgNPs on the ontogenesis of the rat cerebellum after exposure of AgNPs during pregnancy. we used 60 female pregnant rats divided in to three group, each contain 20 female, (G1) treated with 2mg/kg /day suspension of silver nanoparticles (Ag NPs) (G2) treated with 20mg/kg/day AgNPs from first da