What are the 4 properties of gypsum products?

Properties of ideal model material (gypsum products):

1- Dimensional stability,no expansion or contraction during or after setting. 2- High compressive strength to withstand the force applied on it. 3- Hardness, soft material can be easily scratched. 4- Reproduce the fine details.

What are gypsum products used for in dentistry?

What is gypsum and its types?

Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO 4·2H2O. It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, blackboard or sidewalk chalk, and drywall.

What are the five forms of gypsum?

There are five basic forms of gypsum: selenite (transparent and some of the largest crystals found on earth), satin spar (fibrous and silky), alabaster (fine-grained, translucent white, used in ornamental works), rock gypsum (the most common form), and gypsite (soft, earthy, impure form).

What is Type 3 dental stone?

Mounting Stoneâ„¢ Type 3 Dental Stone

A high strength, fast setting, low expansion, articulating stone. Originally developed for implant cases where a low expansion articulating material is desired.

What are uses of gypsum?

Crude gypsum is used as a fluxing agent, fertilizer, filler in paper and textiles, and retarder in portland cement. About three-fourths of the total production is calcined for use as plaster of paris and as building materials in plaster, Keene’s cement, board products, and tiles and blocks.

What are gypsum products?

Gypsum (hydrous calcium sulfate) is a popular raw material for manufacturing various construction products, such as plasters, drywall (wallboard or plasterboard), ceiling tiles, partitions, and building blocks.

What are the ideal properties of gypsum products?

Properties of ideal model material (gypsum products): Dimensional stability, no expansion or contraction during or after setting. High compressive strength to withstand the force applied on it. Hardness, soft material can be easily scratched.

What is dental plaster used for?

Dental Plaster is a formulated hemihydrate plaster (CaSO4. ½H2O) produced from naturally occurring gypsum mineral. It is off-white in colour. It is used in dentistry during the flasking operation in the production of dentures.

What is Type 5 dental stone used for?

Synthetic Type 5 Modified Hard Dental Stone , with high setting expansion to compensate the high contraction of some impression materials,ideal for all working models,master and sectioned models,for orthodontic devices, full/partial dentures, inlays,onlays,crowns,bridges on implants,including models for CAD/CAM .

What is Type IV dental gypsum?

TYPE 4: Gypsum with an ISO rating of 4 can be a specialty stone, or more commonly known as a die stone. Most cases are done using a low expansion die stone, with an expansion of around . 08.

What is the strongest gypsum product?

High-strength stone is the strongest and most expensive of the three gypsum products, and it is used mainly for making casts or dies for crown, bridge, and inlay fabrication.

What is the difference between a type IV and type V gypsum products?

IV – Dental stone (high strength); V – Dental stone (high strength, high expansion). Among many dental applications, gypsum is used for making casts on which various types of prosthetic pieces can be constructed.

What is Type 4 stone?

Type 4 stones have high compressive strength and low expansion, ideal for making master models. Each stone developed by Zhermack has specific technical characteristics for each individual application.