Background: Although bleaching is typically considered a safe procedure, various investigations have found minor negative effects and changes in mineral composition. The aim was to Evaluate and compare the efficacy of using Nanohydroxyapatite serum on surface microhardness of enamel surface before and after bleaching with chemically cured Boost bleaching. Material and methods: ten sound human permanent upper and lower premolar teeth were used and their roots were removed 2 mm apically to the cementoenamel junction, the crowns were sectioned mesiodistally into two halves buccal and lingual/palatal, the buccal surface was further subdivided into two halves. The samples were embeded in an acrylic resin, resulting in 30 specimens divide

   This research aims to introduce the general tax on sales in gordan and the most important concepts related to this type of taxes and identify the  most  on characteristics and stand on its role in supplying the general budget of the necessary fundig to cover the over head of the state and the factorsinfluencing it and whether such a tax has been able to chieve the desired goals.including in contribute to an important and growing role in puplic revenues or not to be able to achieve these goals through the use of descriptive and analytical technique based on the data and information relevant.wasreached some conclusion and  recommendations was most important is that the general sales tax comes in

Infertility is a disease of the reproductive system defined by the failure to achieve a clinical pregnancy after 12 months or more of regular unprotected sexual intercourse. Worldwide, infertility affects approximately 15% of all couples trying to conceive. Male infertility is responsible for about 50% of the infertility cases. Chromosomal abnormalities and Y-chromosome microdeletions are the most common genetic causes of male infertility. Klinefelter syndrome (KS) is the most prevalent factor of the chromosomal abnormality in the infertile male. Azoospermia Factor (AZF) microdeletions located on the Y chromosome are one of the recurrent genetic cause of male infertility. This study aims to investigate the prevalence of chromosomal anoma

This study is qualitative, it illustrates H.G. Wells\\'s The Time Machine through the scientific and social framework of the Victorian Era. Wells\\'s portrayal of future societies examines the rapid technological progress and social changes of the 19th century. The analysis scrutinizes the division between the Eloi and the Morlocks, tracing the consequences of social division. To meet the objective of the study, Victorian frame of mind is utilized to examine the class struggle that is symbolized by the Eloi and the Morlocks. The analysis highlights the economic and social effects of industrialization and how Wells examines the capitalist system and its impact on human relationships and class division. The study also utilizes concepts from D

In this study Candida speices was diagnosed in 26 swab samples from patients with denture stomatitis , investigates the antagonism activity of Lactobacillus was investigated against the yeast of Candida albicans in vitro.Results revealed that The inhibition effect of Lactic Acid Bacteria against C.albicans was examined in solid medium, L.plantarum gave higher inhibition average 11mm followed by L.acidophillus with average 9 mm and, L.fermentum , L.casei with averages 7 mm. Whereas the filtrates, the highest inhibition zone were 20 and 16 mm by L. plantarum and L.acidophillus, respectively.