Tarnishing, corrosion and stress corrosion cracking (SeC) of gold alloys are related phenomena. They present problems when they occur in gold jewellery, dental gold alloys and electronic devices. They are exploited, however, in the depletion gilding and finishing of gold jewellery; and in the extraction, refining and fire assaying of gold. There is still much that is not known about these pheno...

Microstructure of commercial dental alloys and their amalgams were studied primarily by x-ray diffraction, optical metallography, scanning electron microscopy, and x-ray energy dispersive spectroscopy. X-ray diffraction revealed more phases than normally reported in these materials. Presence of new phase was discussed and their formation mechanism understood. Some phases having interacting 2 th...

Basic factors that influence the physical metallurgy and the mechanical properties of cobalt-base alloys are discussed in this study; these factors include the coherency of the interphase interface, the stacking fault energy, and the average electron hole number. Control of these factors and considerations of corrosion resistance and body compatibility determined the compositions for alloys tha...

The microstructure, mechanical properties, and corrosion behavior of binary Ti-xPt alloys containing 5, 10, 15 and 20 wt% Pt were investigated in order to develop new Ti-based dental materials possessing superior properties than those of commercially pure titanium (cp-Ti). All of the Ti-xPt (x = 5, 10, 15, 20) alloys showed hexagonal α-Ti structure with cubic Ti₃Pt intermetallic phase. The mech...

At present, many amalgam alloys are commercially available. These alloys can be classified as having low and high copper contents and, also in terms of being lathe-cut, spherical or admixed. The various claims of the manufacturers concerning the advantages of their products in terms of both composition and particle shape, often causes confusion to the practitioner. Therefore, it is important to...

Ti and Ti alloys have been widely applied to biomedical and dental fields and the demands for their applications have increased gradually in these fields. Ti and its alloys have been used as biomaterial because of their high corrosion resistance, low toxicity, low elastic modulus and low density. Their defects are low shear strength, low wear resistance, low weldability, low formability and low...

Dental alloys for direct metal laser sintering (DMLS) are available on the market today, but there is little scientific evidence reported on their characteristics. One of them is the release of ions, as an indicator of the corrosion characteristics of a dental alloy. Within this research, the difference in the elution of metals from DMLS and cast (CM) samples of Co-Cr-Mo dental alloy in saliva-...

Microplasma welding is a less expensive alternative to laser welding in dental technology. The aim of the study was to highlight discontinuities present in the microplasma welded joints of dental base metal alloys by visual analysis. Five base metal alloys designated for fixed prostheses manufacture were selected for the experiments. Using these plates, preliminary tests were conducted by micro...

Aiming at developing a dental titanium alloy with better mechanical properties and machinability than unalloyed titanium, a series of Ti-Nb alloys with Nb concentrations up to 30% was made. They were cast into magnesia-based molds using a dental casting machine and the mechanical properties and grindability of the castings were examined. The hardness of the alloys with Nb concentrations of 5% a...

Three isomers of methacryloyloxyethyl naphthalenetricarboxylate anhydrides (MENTA-126, -236 and -184) were synthesized, and their adhesiveness to teeth and non-precious dental alloys was investigated. The MENTA resins initiated by TBB-O showed about 12-13MPa of the bond strength on treated enamel and 10-12.5MPa on treated dentin after 120 thermocycles, while, after the equal thermal cyclings, t...