What are the properties of an impression compound?
Impression compound is a thermoplastic material with a glass transition temperature of about 55–60°C. Above its glass transition temperature it becomes soft and will take up a new form. On cooling to mouth temperature, it hardens and can be removed, retaining an impression of the oral cavity.
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.
What factors affect the flow of impression compound?
The flow or viscosity of an impression material is dependent on the filler content. There are four basic categories: low (syringe or wash material), medium (one-step monophasic material), high (tray material), and very high (putty material).
What type of material is impression compound?
Impression compound is a thermoplastic material; it is presented as a sheet of material, which is warmed in hot water (> 55–60 °C) for one minute, and loaded on a tray prior to impression taking. Once in the mouth, the material will harden and record the detail of the soft tissues.
What are the advantages and disadvantages of impression compound?
- Clinical use: occasionally for mucostatic impressions for flabby ridge.
- Setting time: two to three minutes.
- Advantages: hydrophilic, good reproduction of details, good dimensional stability.
- Disadvantages: brittle, no recovery from deformation, excess saliva negatively effects detail replication.
What are the requirements of an ideal impression compound?
Requirements of an ideal impression compound:
Should become hard uniformly throughout without discrepancies and distortion. It should not be harmful to Oral tissues when it is elastic in plastic state. Should not be harmful and not have toxic or Irritating materials to Oral tissue.
What is the use of impression compound?
Impression compound is usually used for taking primary impressions of the edentulous ridge prior to the construction of a custom-made impression tray for complete dentures.
What is compound in dentistry?
Compounding is a method of creating personalized medications for patients where separate ingredients are combined to create a formulation that is tailored to each individual. …
What are examples of impressions?
An example of impression is the mark you make when you press your finger into clay. An example of impression is when someone who meets you continues to talk on and on about you. An initial or single coat of color or paint. A humorous imitation of the voice and mannerisms of a famous person.
How will you prevent distortion during impression making?
What can you do: Ensure the impression tray is the proper size prior to taking the impression and the material has excellent elastomeric properties. Remove the impression along the axis of prepared the tooth.
What is the condition that allows shrinkage and distortion of an alginate impression due to leaving the impression exposed to open air?
If an alginate impression is stored in water or in a very wet paper towel, the alginate will absorb additional water and expand. This condition is called imbibition. If an alginate impression remains in the open air, moisture will evaporate from the material, causing it to shrink and distort.