Posted by : Razib smile Monday, July 8, 2013
What is Impression ?
In dentistry, an impression is defined as the negative imprint of the natural standing teeth & surrounding supporting oral tissues.
Classification of Impression .
1. Primary Impression
2. Wash Impression
3. Final Impression
Primary Impression : When the impression is taken to see the gross outline of the teeth & oral cavity at first stage usually by the impression compound is primary impression .
Wash Impression : If an impression is taken to correct an incomplete impression with a thin section of alginate or paste impression material over the incomplete impression is called wash impression .
Final impression : The impression of the edentulous jaw from which a final dental construction is carried out is called wash impression.
Why we Take Impression ?
We know that the oral tissues are soft & sensitive , So it is not possible to make artificial appliances or restoration in oral cavities. For this reason, we take an impression of oral cavity & subsequently on which a model or cast is prepared and other steps of dental construction are carried out.