dental cast, surveying

Question 1

what is the difference between primary and master cast

Answer 1

primary cast used for diagnostic and study, poured in POP or lab stone, used to do treatment planning, special tray

master cast used for working, fabrication of prosthesis, usually poured in silky rock or lab stone

Question 2

what is a good cast

Answer 2

have a robust base, precise anatomical landmarks, no bubbles, clean and tidy, sulcus preserved

Question 3

what is the purpose of surveying

Answer 3

to eliminate unwanted undercut

to ensure occlusal plane is parallel to horizontal plane

to create guide plane, evaluate proximal surfaces of abutment for parallelism

to. check for adequate and relatively equal undercuts for retentive arms on all abutment teeth( for the clasp)–> only terminal third is undercut