NON elastic impression material by Qaisar Abbas student of bs dental aT INSTITUTE OF HEALTH SCIENCES .

1. Name:Qaisar Abbas
Discipline:Bs Dt

2. IMPRESSION
 It is the negative imprints of the
natural teeth and their supporting
tissue.
 The impression stage is the first of
many stages involved in the
production of
dentures,crowns,bridges,orthodontic
Appliances etc.

3.  IMPRESSION MATERIAL
 Any substance and combination of substance
Used for making an impression or negative
reproduction.
 IMPRESSION TECHNIQUE
 A method used in making negative likeness.
 IMPRESSION TRAY
 A receptacle used to carry and confine plastic impres
sin material when making an impression of oral struc
tures.

4. 1)ELASTIC IMPRESSION MATERIAL
 Elastic impression material no capable of
accurately reproducing both the hard and soft
structure of the mouth.
 Classification
 Reversible hydrocolloid
AGAR
 Irreversible hydrocolloid
ALGINATE

5.  4 Main types of products from the group of
impression matrials classified as non-elastics
material.
1. Impression plaster
2. Impression compound
3. Impression waxes
4. Zinc oxide

6.  Similar in composition to the dental plaster
used to construct models and dies.
 Beta calcium sulphate hemihydrate ,when
mixed with water reacts to form calcium
sulphate dihydrate.
 Water powder ratio is very high (0.60).
 Normally used for modelling plaster.

7.  Retardar (borax)
 Anti expansion agent
 Accelerator (potasium sulphate )

8. Thermoplastic resembling
Two type;
1)Low fusing compound – green stick compound
 Medium fusing compound (impression
compound )
2)High fusing compound (tray compound )

9.  Sheets for impression of edentolous ridges
 Sticks for border extention of impression and
trays .
 For single tooth impression with copper ring
technique.

12.  Low melting paraffin wax and bees wax
 Readily flow at mouth temperature
 Soft at room temperature
 Used to record complete impression
 Used in impression of maxillo-facial defect
patient.

14.  Supplied as 2 paste system,
 White paste –base
 Blue paste-inhibator,catalyst