Thesis (M.Sc.) - Cairo University - Faculty of Oral and Dental Medicine - Department of Operative Dentistry

This study aimed to examine the surface roughness and microhardness of several glass ionomers based restorative materials under the influence of exposure to variable pH solutions. Due to the chemical adhesion to tooth structure and fluoride release conventional glass ionomer has been highly used in the world of dentistry. On the other hand it has many limiting properties like high wear, low fracture strength and moisture sensitivity which led to do further modifications to the material like modification in powder to liquid ratio,other modification is the addition of metal particles(Kramer and Frankenberger, 2001) (Upadhya and Kishore,2005) (Hentegrakool et al,2011)(Bala et al 2012) In the current study silver reinforced glass ionomer ketac silver was used. The ketac silver contain silver-tin alloy fibers or flakes sintered to the glass-particles for a better incorporation of the metal particles into the cement matrix. This should increase the mechanical proprieties but conventional glass ionomer still having the best properties and clinical performance due to dense highly packed glass particles of different size (xie et al 2000) (Kramer and Frankenberger 2001)

Issued also as CD