INTRODUCTION:
The majority of impressions taken by orthodontists are used for pre- and post- records of dental arches.
“Restorations can be as true as your impressions”.
The underlying principle emphasizes the need for complete and accurate impression and highlights the importance of clinical impression procedures.
Purpose of impression is the formation of ‘positive’ model of the proper physical dimension, shapes and spatial relationship of these structures.
DEFINITIONS
Impression – An imprint or negative likeness of the teeth and/or edentulous areas where the teeth have been removed made in a plastic material which becomes relatively hard or set while in contact with these tissues.
-Boucher
Impression material – Any substance or Combination of substances used for making impression or negative reproduction.
-GPT 8