Definition:
Cast duplication is the process of reproducing a working cast (usually made of stone) to obtain an identical copy without altering the original model.
Uses of Cast Duplication:
When the original cast needs to be preserved for reference.
To fabricate removable partial denture frameworks without damaging the master cast.
In implant dentistry, to duplicate diagnostic wax-ups.
For teaching, research, or case documentation.
Materials Used:
Agar hydrocolloid (reversible hydrocolloid) → most common.
Silicone duplicating materials.
Alginate (less accurate, used for study casts).
Procedure (General Steps):
Place the master cast in a duplicating flask.
Pour in duplicating material (e.g., agar hydrocolloid).
Allow it to set, then remove the master cast → leaving a mold.
Pour dental stone or refractory material into the mold.
Obtain the duplicate cast (identical copy).