7414

6920

كارشناسي ارشد

استخراج فلزات

اصفهان : دانشگاه صنعتي اصفهان

1391

دوازده، 94ص.: مصور، جدول، نمودار

ص.ع. به فارسي و انگليسي

محمدحسين فتحي، احمد منشي

وجيهه السادات مرتضوي، فرزاد شيراني

3/10/91

محمدعلي گلعذار، علي سعيدي

1396/09/22

كتابنامه

مواد

مهندسي مواد

1399/11/28

ID6920

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

95 Synthesis of Amalgam Titania Nanocomposite in Order to Improve the Properties of Dental Amalgam Neda Bahremandi Tolou Bahremandi n@gmail com Date of submission April 14 2012 Department of Meaterials Enginnering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor Mohammad Hossain Fathi Fathi@cc iut ac ir Ahmad Monshi a monshi@cc iut ac ir Abstract Dental amalgam is one of the most widely used dental fillings and it has been used since 180 years ago Since then many research has been continued to improve the properties Most of these investigations is about corrosion behavior of dental amalgam in different situations The aim of this study was preparation of amalgam titania nanocomposite via adding nanoparticles of titania to amalgam alloy powder to improve some properties Diferrent weight percents of nanoparticles of titnia were added to the amalgam alloy powder and amalgam titania nanocomposites were produced For improving antibacterial properties of dental amalgam silver doped titania nanoparticles were synthesized and were added to amalgam alloy powder XRD SEM EDS TEM CCS techniques potensiodynamic corrosion and immersion corrosion tests were employed Agar dilution was used for Ag doped titania nanoparticles and spectrophotometery was applied for dental amalgam which contain Ag doped titania nanoparicles to evaluating antibacterial properties Phase structure evaluation showed that no new phase is developed In the amalgam titania nanocomposites SEM micrographs and EDS analysis indicated the present of titania on the surfaces of phases of dental amalgam Large pores could be identified by adding 2 and 3 wt nanoparticles of titania reducing compressive strength and corrosion resistance Compressive strength tests indicated that the 1 wt of nanoparticles of titania in the dental amalgam increased compressive strength about 20 MPa while it decresed for amalgam titania nanocomposites contain 2 and 3 wt nanoparticles of titania Also potensiodynamic corrosion tests showed a little change in the current corrosion density by adding 1wt nanoparticles of titania but in the more than 1 wt it decresed strongly So the best result was observed about amalgam titania nanocomposite by 1 wt nanoparticles of titania The immersion tests were performed 2 hours after fabrication of the samples in the artificial saliva at 37 1 C to determined the released mercury Releasing of mercury at early hours is a disadvantage of dental amalgam Reduction of released by adding nanoparticles of titania was a promising result Phase structure evaluation showed anatase phase of TiO2 in all Ag dopped titania nanoparticles and scherrer s equation indicated crystallite size of 24 4 nanometer TEM showed spherical shapes of Ag doped titania nanoparticles and indicated that titania and silver particles are 30 5 and 15 3 nanometers respectively Agar dilution showed increasing the antibacterial properties by doping silver on the surfaces of nanoparticles of titania Minimum Inhibiton Concentration MIC of 3 mg ml for all nanopowders could inhibited bacteria growth The spectrophotometery results of different compositions of dental amalgam contain Ag doped titania nanoparicles indicated decreasing of optical density and bacteria growth for Ag doped titania nanoparticles Keyword Dental amalgam titania Ag doped titania antibacterial properties corrosion

محمدحسين فتحي، احمد منشي

وجيهه السادات مرتضوي، فرزاد شيراني

محمدعلي گلعذار، علي سعيدي