What is amalgam phase down?
What is amalgam phase down?
Phase down of dental amalgam: A task to reduce the use of dental amalgam through increased prevention, health promotion, and research on advanced restorative materials and techniques – maintaining or improving adequate clinical performance.
What are the phases of amalgam?
With the conventional amalgam alloy, the reaction between the Ag3Sn (γ) phase and the mercury results in the formation of the γ1 phase, which is a body-centred cubic mercury – silver phase with a mercury-silver ratio between 3:2 and 8:5, and the γ2 phase, a hexagonal tin-mercury phase of mercury – tin ratio between 1:6 …
Which phase is strongest in amalgam?
gamma phase
The first phase, called the gamma phase (γ), is the silver alloy phase. It is the strongest phase and has the least corrosion.
Which phase of amalgam is the weakest?
Sn8Hg (γ2 phase) was considered to be responsible for this problem. This phase has been shown to be the weakest phase in the set amalgam and is subject to corrosion, particularly at the tooth-amalgam interface.
What are the two main components of dental amalgam?
Dental amalgam is a dental filling material used to fill cavities caused by tooth decay. Dental amalgam is a mixture of metals, consisting of liquid (elemental) mercury and a powdered alloy composed of silver, tin, and copper.
What is gamma phase of amalgam?
Formation of the gamma-2 phase (γ-2) is a disadvantage of amalgam used in the past (= conventional amalgam). The γ-2 phase results from the hardening/setting reaction of mercury with the metal powder and consists of a mixture of tin and mercury (Sn8Hg).
What is creep in amalgam?
The pro- gressive deformation of a material at constant stress is called creep. In testing of dental amalgam, creep refers to the deformation of an amalgam under a compressive stress of 36 MPa of a 7 d old specimen (ISO, International Or- ganization for Standardization’s proposal for International Standard 1559).
What is delayed expansion in amalgam?
Delayed expansion—The gradual expansion of a zinc-containing amalgam over a period of weeks to months. This expansion is associated with the development of hydrogen gas, which is caused by the incorporation of moisture in the plastic mass during its manipulation in a cavity preparation.
What are the components of amalgam?
Dental amalgam is a dental filling material used to fill cavities caused by tooth decay. Dental amalgam is a mixture of metals, consisting of liquid (elemental) mercury and a powdered alloy composed of silver, tin, and copper. Approximately half (50%) of dental amalgam is elemental mercury by weight.
What is non gamma 2 amalgam?
Cavex NON-Gamma-2 is a dispersed, high silver gamma-2-free amalgam. The amalgam has been proven effective and has already proven its reliability and wear resistance in dental clinics. The self-activating and resealable capsule offers optimum safety both during and after mixing.
What causes amalgam creep?
Both corrosion and creep have been identified as possible contributors to this type of failure. The stresses that induce creep may arise from the continued setting expansion of the amalgam, the formation of corrosion products, mastication, or from the thermal expansion of the amalgam during ingestion of hot foods.