operative

Question 1

In burs how many no of blades

Answer 1

Cutting= 6 blades
* Finishing= 12 blades
* Fine finishing= 18-24 blades
* Ultra fine finishing= 30-40 blades

Question 2

cutting instrument formula

Answer 2

1st number= blade width (10= 1mm)
* 2nd number= cutting edge angle (omitted if perpendicular to the blade)
* 3rd number= blade length (7= 7mm)
* 4th number= blade angle (14= 14% of 360˚)

Question 3

Medium-speed handpiece

Answer 3

12,000-2 lakh rpm

Question 4

RDT <0.5 mm

Answer 4

liner,base(sealer,bond,cement)

Question 4

• Over-trituration

Answer 4

warm, wet, soft, set too quickly

Question 5

normal mix

Answer 5

shiny, smooth

Question 6

Spherical alloy particles

Answer 6

– Microspheres of
various sizes
– Easier to condense
– Stronger
– Sets faster

Question 7

mercury forms

Answer 7

Methylmercury= organic, most toxic
* Elemental= liquid metallic, in dental amalgam
* Mercury salts= inorganic

Question 8

Incipient/Reversible

Answer 8

on
smooth surface appears
opaque white when airdried
and seems to
disappear when wet

Question 9

point angle

Answer 9

junction of 3 walls

Question 10

Slots

Answer 10

– At least 1mm deep
– At least 1mm long
– 0.5mm inside DEJ