TRIMMING, CUTTING Flashcards
Example of disposable Embedding mold
Paper boats
Peel away
Plastic ice trays
L shape strip or brast or metal
Leuckhart’s embedding mold
Series of interlocking plates
Compound embedding mold
Tissue is arranged in precise position in the mold during embedding
Orientation
Three essentials parts of microtomy
Block holder
Knife carrier and knife
Pawl, ratchet feed wheel and adjustment screw
Also known as cambridge by Paldwell trefall and simplest
Rocking microtome
Other name for sliding microtome
Adams
Most commonly used microtome
Rotary microtome
What specific type of sliding microtome when the block holder is moving?
Base sledge
What specific type of sliding microtome when the knife is moving
Standard sliding
Thickness of tissue sections
Paraffin sections- 4-6 u
Celloidin sections- 10-15 u
Ultrathin sections- 0.5 u
Disposable blades- 2-4 u
Describe biconcave knife
Measures 120 micra
Both sides concave
For paraffin embedded tissue using rotary microtome
Describe plane wedge knife
100 micra
Both side straight
For frozen section- extremely hard and tough specimen in paraffin blocks using base-sledge microtome
Plane-concave knife
25 micra
One side is flat, other side is concave
If less concave- celloidin embedded tissue using sliding microtome
More concave- paraffin embedded tissue using rotary and rocking microtome
Sharp cutting edge that cuts 2-4 u thick sections
Disposable blades
Describe glass knives
Trimming and semi-thin sectioning
Used to block resin block for electron microscopy
Diamond knives
Angle formed between the cutting edge, normally 27 to 32 °C
Bevel angle
Angle formed by the sides of the wedge knives normally 14-15 °
Wedge angle
Angle formed between the cutting facet presenting to the block and the surface of the block, normally 0 to 15 °
Clearance angle
Removal of gross nicks
Honing
Purpose of honing
To remove irregularities from the knife
Direction in honing
Heel to toe (edge first)
Counterpart of honing that removes burr
Stropping
