The damping capacity and mechanical properties of Mg-6Al-1Zn alloy after heat treatment were investigated. The damping characteristics of un-heat-treated, solution treated, and aged Mg-6Al-1Zn specimens were determined by measuring the damping ratio and the logarithmic decrement of free vibrations of a bending beam clamped at one side. The microstructural evaluations confirmed that the β-Mg17Al...

Since luting cement is used for fixing cast restorations to their abutments, the cement surface at the junction between cast and tooth is exposed to oral environment. The conventional cement so far used does not adhere to the tooth and is slightly soluble into saliva and gingival fluid1,2). Consequently, the microleakage and subsequent recurrent caries seem to develop at this junction. Recently...

This study analyzes international historical trends in the use of different types of materials in dental practice. The author describes the chemical properties of their ingredients and the potential and observed adverse effects in patients and dental technicians resulting from clinical or occupational exposure to various metals like beryllium, used to produce metal alloys. The growing use of va...

The use of metals in dentistry has great therapeutic advantages in many fields of dentistry, such as orthodontics, prostheses, conservative dentistry since its origins and more recently implantology [2]. Likewise, metals can be used on numerous and varied substrates: enamel, dentin, ceramics, resins or other metals [1]. Examples of adhesion of enamel or dentin to metals, orthodontic bands and b...

The aim of this study was to develop an effective primer to improve the adhesive property between all kinds of dental metal alloy and resin cement. To this end, we synthesized N,N'-dimethacryloylcystine (NDMCC) which had both disulfide functional group (to improve adhesion between precious metal alloy and resin) and carboxyl group (to improve adhesion between non-precious metal alloy and resin)...

Concerns over allergic reactions to dental restorative and orthodontic materials have increased in the past few years. The incidence appears to be quite low, but increases with increased quantity and duration of exposure to a causative antigen. In most instances intraoral allergies result in a type IV, delayed contact response that may manifest in various ways including lichenoid reactions, bur...

Worldwide publicity of the amalgam controversy has intensified the growing concerns on its utilization and safety. This controversy has grown beyond the confines of the dental profession itself and has become an emotional public health issue. Amalgam has been the material of choice for restoring posterior teeth for more than 100 years. Presently, there has been a shift toward resin composite an...

The isothermal age-hardening behaviour in the commercial dental gold alloys containing palladium was studied by means of resistometric, hardness, X-ray and electron microscopy. Drastic overageing occurred following prolonged ageing. The mechanism of the overageing was interpreted as a loss of coherency at the interfaces of the adjacent lamellae which consists of the equilibrium AuCu I ordered p...

Dental diseases are among the most common ailments, and dentists in the United States spend over 50% of their time in dental practice rebuilding carious, malformed, and traumatically injured teeth. It is logical, therefore, that the majority of the dental school curriculum is devoted to the diagnosis, prevention, and treatment of teeth with anomalies. Dentists have several choices of materials ...