LABORATORY PROCEDURES IN FIXED PROSTHODONTICS

TOPIC: INSERTION, RELINING AND REBASING

🎯 KEY POINTS:

🔹Lost wax technique was first used in casting of alloys by W.H. Taggart (1906).

🔹Gypsum-bonded investment material is used for casting gold alloys.

🔹Pickling is a method of cleaning gold casting by hot acid solution for several minutes.

🔹Phosphate-bonded investment is used for casting metal–ceramic alloys having high-melting temperature.

🔹The minimum fineness required for dental solder to be corrosion resistant is 580 fine.

🔹Beryllium added to base metal alloys to control oxide formation is a carcinogen.

🔹Rounded margins on the casting may be caused by wax which is not completely eliminated during burn out procedure.

🔹Expansion of the investment by heat during elimination of the wax is called thermal expansion.

🔹There are two techniques in which the impression can be poured with dowel pins, namely, prepour and postpour techniques.

🔹Tamping effect, i.e. the heavier particles settle at the bottom and the liquid part comes to the top.

🔹Metamerism is a phenomenon of an object which appears different under different sources of light.