What materials are used for impressions?

Four types of elastomeric impression materials are available in the market: addition silicone, also known as polyvinyl siloxanes (PVS), condensation silicone, polyether, and polysulfide. Elastomers can present in different consistencies, including putty, heavy body, medium body, and light body.

Can condensation silicone be electroplated?

It can be electroplated with silver or copper. However, hydrophillic silicones are more difficult to electroplate because of the surfactant added. It has low flexibility and is harder than polysulfides.

What is polyether impression material?

Polyether impression material is an elastic-type material, as are the polysulfide and silicone materials. These materials have demonstrated good accuracy in clinical evaluations and are thixotropic, which provides good surface detail and makes them useful as a border molding material.

Which impression material is the most widely used material?

Alginate
Alginate is currently one of the most popular impression materials. It is supplied as dust-free powders. After mixing with proper amount of water in a rubber bowl with a spatula, it is ready for impression taking.

What is putty impression material?

Silicone impression material consists of a base and catalyst in a putty consistency. … They are available in a range of viscosities including light, medium, heavy and very high viscosity (or putty) material. When taking a putty impression it is usually combined with a low viscosity silicone.

What are rubber impression materials?

Rubber Impression Materials

Synthetic oligomers of various molecular compositions and sizes are supplied for use as dental impression materials. … These oligomers are viscous fluids that can polymerize further through the processes of chain lengthening and cross-linking to form a viscoelastic solid rubber.

Which impression material has the best wettability?

Statistical analysis supported four conclusions: No significant difference was found between the two surfactants. Both surfactants were significantly better than the control (water). Polyether impression materials were superior in wettability to the other elastomeric impression materials tested.

What is the most accurate impression material?

The polyethers produced the most accurate complete-arch replicas. The second most accurate were the vinyl polysiloxanes, followed by the polysulfides and the irreversible-reversible hydrocolloids. The least accurate were the reversible hydrocolloids and the irreversible hydrocolloids.

What is rigid impression material?

Rigid impression materials include plaster and compo/zinc oxide-eugenol; however, since they cannot engage the undercuts, their application is limited nowadays. Elastic impression materials can be further divided into hydrocolloid and elastomeric impression.

Which impression materials are hydrophilic?

In contrast to addition silicone impression materials, polyether impression materials are hydrophilic, with a high affinity to surfaces such as tooth and soft tissue. Polyether materials have intrinsic hydrophilicity compared to the hydrophilicity produced by adding surfactants to the impression material.

Which impression material is hydrophobic?

Vinyl Polysiloxane Impression materials (VPS) are most frequently used as the impression material in fixed prosthodontics. As VPS is hydrophobic when it is poured with gypsum products, manufacturers added intrinsic surfactants and marketed as hydrophilic VPS.

What type of impression material is alginate?

hydrocolloid impression material
Alginate is an elastic, irreversible hydrocolloid impression material. Irreversible hydrocolloid impressions form an inseparable part of indirect restorations.

What is hydrocolloid impression material?

Hydrocolloids were the first elastic impression materials available to dentists. When mixed, they form a viscous liquid that can be seated over oral structures. The liquid sets, becoming a gelatin-like solid that is flexible enough to be drawn over undercuts without significant permanent deformation.

What is silicone impression material used for?

Silicone, being a more elastic material, allows for more uses for dentists than alginate. With regard to impressions, for example, silicone is used in cases of root canals, soft structures and bone tissues, in addition to implants and functional impressions of full dentures.

What is addition silicone impression material?

An elastic final impression material used to construct cast restorations, dental prostheses, and other appliances. It is made from a vinyl polysiloxane paste mixed with a platinum salt catalyst.

Is Agar Agar a hydrocolloid?

Agar is a reversible hydrocolloid because it can pass repeatedly between highly viscous gel and low viscosity sol simply through heating and cooling.

Is gelatin a hydrocolloid?

Gelatin, a unique hydrocolloid, serves multiple functions in a wide range of applications. The main sources of gelatin include pigskin, cattle bones and cattle hide.

How is agar different from alginate impression material?

The key difference between agar and alginate is that agar is obtained from red algae, whereas alginate is obtained from brown algae. Moreover, in the formation of gel, agar undergoes a physical change while alginate undergoes a chemical change.

What is impression compound?

Impression compound is a mucocompressive, thermoplastic (i.e., it softens when heated and hardens when cooled) and rigid impression material that was invented by British dentist Charles. … Two types of impression compounds are available – Type 1 which is low fusing with a fusion temperature of approximately.

How do I make an agar impression?

What is impression plaster?

Plaster of Paris (impression plaster)

Plaster of Paris is traditionally used as a casting material once the impression has been taken, however its use as an impression material is occasionally useful in edentate patients. The tissues are not displaced during impression taking, hence the material is termed mucostatic.