ADDITION SILICONE

- Hydrophobic
- Polyvinyl siloxane – another name
- Catalyst – platinum
- By-product – H2 gas – smaller molecule
- Least dimensional change
- Most accurate impression material preferred for onlay cavity
- OSMF patients (less mouth opening)
- Never pour immediately, wait for 30 mins for the release of H2 gas – if not pin-point depression on cast
- Expensive – disadvantage
- Only vinyl gloves – no latex