Biomaterial Database

Thermal behaviour of casting investment during setting. 1995

K Wakasa, and M Yamaki

Department of Dental Materials, Hiroshima University, School of Dentistry, Japan.

The aim of this study was to examine the thermal reactions of silica-sol liquids for mixing investment powders using differential thermal analysis (DTA) and also the setting behaviour of the mixed powders using differential scanning calorimetry (DSC). The silica-sol liquids showed the appearance of vapourization (around 100 degrees C as a peak temperature) and combustion (200-300 degrees C) in DTA measurement. Mixed silica-sol investment exhibited the setting behaviour with an exotherm in the DSC measurement representing that greater peak time, setting time and heat in mixed investment than with gypsum-bonded investment.

UI	MeSH Term	Description	Entries
D011208	Powders	Substances made up of an aggregation of small particles, as that obtained by grinding or trituration of a solid drug. In pharmacy it is a form in which substances are administered. (From Dorland, 28th ed)	Powder
D002133	Calcium Sulfate	A calcium salt that is used for a variety of purposes including: building materials, as a desiccant, in dentistry as an impression material, cast, or die, and in medicine for immobilizing casts and as a tablet excipient. It exists in various forms and states of hydration. Plaster of Paris is a mixture of powdered and heat-treated gypsum.	Dental Gypsum,Dental Stone, Artificial,Gypsum,Plaster of Paris,Alabaster,Anhydrous Sulfate of Lime,Artificial Dental Stone,Calcium Sulfate (1:1), Dihydrate,Calcium Sulfate (1:1), Hemihydrate,Calcium Sulfate (2:1),Calcium Sulfate Dihydrate,Calcium Sulfate, Anhydrous,Calcium Sulfate, Dihydrate,Calcium Sulfate, Hemihydrate,Calcium Sulphate,Drierite,Gypsite,Gypsum, Dental,Karstenite,Stone, Artificial Dental
D002152	Calorimetry, Differential Scanning	Differential thermal analysis in which the sample compartment of the apparatus is a differential calorimeter, allowing an exact measure of the heat of transition independent of the specific heat, thermal conductivity, and other variables of the sample.	Differential Thermal Analysis, Calorimetric,Calorimetric Differential Thermal Analysis,Differential Scanning Calorimetry,Scanning Calorimetry, Differential
D003734	Dental Casting Investment	Material from which the casting mold is made in the fabrication of gold or cobalt-chromium castings. (Boucher's Clinical Dental Terminology, 4th ed, p168)	Casting Investment, Dental,Casting Investments, Dental,Dental Casting Investments,Investment, Dental Casting,Investments, Dental Casting
D005782	Gels	Colloids with a solid continuous phase and liquid as the dispersed phase; gels may be unstable when, due to temperature or other cause, the solid phase liquefies; the resulting colloid is called a sol.
D006358	Hot Temperature	Presence of warmth or heat or a temperature notably higher than an accustomed norm.	Heat,Hot Temperatures,Temperature, Hot,Temperatures, Hot
D000431	Ethanol	A clear, colorless liquid rapidly absorbed from the gastrointestinal tract and distributed throughout the body. It has bactericidal activity and is used often as a topical disinfectant. It is widely used as a solvent and preservative in pharmaceutical preparations as well as serving as the primary ingredient in ALCOHOLIC BEVERAGES.	Alcohol, Ethyl,Absolute Alcohol,Grain Alcohol,Alcohol, Absolute,Alcohol, Grain,Ethyl Alcohol
D000433	1-Propanol	A colorless liquid made by oxidation of aliphatic hydrocarbons that is used as a solvent and chemical intermediate.	Alcohol, Propyl,Propanol,n-Propanol,Propyl Alcohol
D012822	Silicon Dioxide	Transparent, tasteless crystals found in nature as agate, amethyst, chalcedony, cristobalite, flint, sand, QUARTZ, and tridymite. The compound is insoluble in water or acids except hydrofluoric acid.	Silica,Aerosil,Aerosil 380,Cristobalite,Quso G-32,Quso G32,Tridymite,380, Aerosil,Dioxide, Silicon,G32, Quso,Quso G 32
D012996	Solutions	The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)	Solution