Lecture 8: Clinical tips and tricks of an ideal complete denture impression

Basic objectives of impression:
a- Denture support
b- Denture retention
c- Stability
d- Maintain the health of the oral tissues
Satisfactory impression required:
a- Healthy denture bearing tissue.
b- Accurate Construction, Extension and positioning of the tray.
c- Impression material & technique suitable for each condition.
Impression should fulfill the following criteria:
1- The impression should be extended to cover all the basal seat area i.e. within physiological tissue limits.
2- Physiologic border molding should be carried out to obtain adequate border seal and denture borders that are in harmony with the anatomic limiting tissues.
3- Adequate space should be provided within the tray for the final impression material.
4- The tray should be properly positioned in the mouth during impression recording.
5- The tray and final impression should be made of dimensionally stable materials.
6- The external shape of the final impression should be similar to the external form of the completed denture.
Factors that complicate impression making:
1- Amount and consistency of saliva:
2- Very thick cheeks:
3- Tone of the facial muscle:
4- Lack of muscular control:
5- The presence of undercut area:
6- Gagging: