223.Which material listed below has historically been the retrofilling material of choice?

a.Composite
b.Zinc-free amalgam
c.Gutta-percha
d. Methyl methacrylate

Ans.b.Zinc-free amalgam

Explanation:A retrofilling (also called a reverse filling or retrograde amalgam filling) is placed to seal the apical
portion of the root canal. This procedure is used when an apicoectom y alone will not yield a good
result. Whenever there is any chance whatsoever that an apical seal may be faulty, a reverse filling
material must be placed.

222.The nucleus involved in papez circuit is

a.Pulvinar
b.Intraluminar
c.VPL nucleus
d.Anterior nucleus of thalamus.

Ans:d.Anterior nucleus of thalamus.

Explanation:Ref Ganong's 22nd ed/256,258

221. Which of the following statement is correct regarding chemical setting of condensation silicone?

a)   Polymerization occurs with repeated elimination of small molecules

b)   Polymerization occurs with elimination of  single byproduct

c)   It occurs by repeated condensation of molecules of monomers

d)   Condensation does not occur at all   ( AIPG 2010  ) (Repeat: AIPG 2007)    \