Metallic biomaterials have been extensively used in orthodontics throughout history. Gold, stainless steel, cobalt-chromium alloys, titanium and its alloys, among other metallic biomaterials, have been part of the orthodontic armamentarium since the twentieth century. Metals and alloys possess outstanding properties and offer numerous possibilities for the fabrication of orthodontic devices suc...

In this study, the grindability of cast magnetic alloys (Fe-Pt-Nb magnetic alloy and magnetic stainless steel) was evaluated and compared with that of conventional dental casting alloys (Ag-Pd-Au alloy, Type 4 gold alloy, and cobalt-chromium alloy). Grindability was evaluated in terms of grinding rate (i.e., volume of metal removed per minute) and grinding ratio (i.e., volume ratio of metal rem...

The aim of the present study is to analyze the electrochemical behavior of five different dental alloys: two cobalt-chromium alloys (CoCr and CoCr-c), one nickel-chromium-titanium alloy (NiCrTi), one gold-palladium alloy (Au), and one titanium alloy (Ti6Al4V), and the galvanic effect when they are coupled to titanium implants (TiG2). It was carried out by electrochemical techniques (open circui...

The purpose of this pilot investigation was to measure the co-efficient of friction of a cast cobaltchromium alloy specimen and three materials commonly found on the guiding surfaces of the teeth. The static .co-efficients of friction between dental cobalt-chromium alloy (before and after electropolishing) and tooth enamel, composite resin, and dental amalgam alloy were measured using an inclin...

The effect of 5 different surface conditioning methods on bonding of metal brackets to cast dental alloys was examined. The surface conditioning methods were fine (30-microm) or rough (125-microm) diamond bur, sandblasting (50-microm or 110-microm aluminum oxide [Al2O3]), and silica coating (30-microm silica). Fifty disc-shaped specimens of 5 different alloys (gold-silver, palladium-silver, nic...

Metal-on-metal (MOM) bearings involving cobalt-chromium (Co-Cr) alloys in total hip arthroplasties are becoming more and more popular due to their low wear. Consequences of corrosion products of Co-Cr alloys are for the most part unclear, and the influence of cobalt and chromium ions on biofilm formation has never been studied. Therefore, the aim of this study was to evaluate how Co-Cr ions aff...

Theoretical considerations that lead to the design of strong and ductile cobalt (Co)base alloys were discussed in part I of this series of articles.' It was hypothesized that the composition 40 Co-30 nickel (Ni)-30 chromium (Cr) is an acceptable compromise for the requirements of an alloy base. It also was found that tantalum (Ta) may have the qualities that are acceptable for an additional ele...

The start of melting as well as the melting range in WC-Co and WC-Ni hardmetals is significantly influenced by the alloy gross carbon content as well as by additives (V, Cr). Both Vanadium and Chromium significantly lower the start of melting but also broaden the melting range, in particular at low carbon content (formation of M6C-phases). As a result, a certain temperature range can be defined...

Microleakage at the junction between the metal alloy and acrylic resin in a removable partial denture may result in discoloration, fluid percolation, and acrylic resin deterioration and Failure of a removable partial denture. Dye penetration test was conducted on eighty specimens each of Nickel-Chromium/Cobalt-Chromium metal-Heat cure acrylic resin. Samples were randomly divided into eight grou...