Plastination Flashcards
What is plastination?
PLASTINATION IS A SPECIALIZED PRESERVATION TECHNIQUE INVENTED BY THE GERMAN ANATOMIST ,PROF GUNTHER VON HAGENS
PLASTINATION IS THE REMOVAL OF WATER & LIPIDS FROM TISSUE & REPLACING THEM WITH A PLASTIC POLMER USING FORCED IMPREGNATION
What is the word plastination derived from?
THE WORD PLASTINATION IS DERIVED FROM A GREEK WORD ‘PLASSEIN’, MEANING TO SHAPE OR MOULD.
How did the idea of plastination come about?
THE IDEA OF PLASTINATION HOWEVER, CAME IN HIS MND WHILE HE WAS STILL AN ANATOMY ASSISTANT, HE WAS PRESENTED WITH A KIDNEY EMBEDDED IN A CLEAR PLASTIC, IT WAS MIND BLOGGING TO HIM AS HE FELT THAT INSTEAD OF PLASTIC BEING AROUND THE SPECIMEN, WHY SHOULD IT NOT BE IMPREGNATED INTO THE KIDNEY
Advantages of plastinated specimens:
SPECIMEN IS DRY AND ODOURLESS
SPECIMEN IS EASILY AND SAFELY HANDLED AND STORED WITHOUT DETERIORATION
SPECIMEN IS NON-PERISHABLE AND HAVE INDEFINITE SHELF LIFE
NATURAL COLOUR OF THE SPECIMEN IS PRESERVED
Types of plastination commonly used:
S10 (SILICON) : SUITABLE TO MAKE DISSECTED BODY PARTS AND WHOLE
ORGANS
E12 (EPOXY) : SUITABLE TO MAKE TRANSLUCENT BODY SLICES
P40 (POLYESTHER) : SUITABLE TO MAKE THIN SLICES OF NEURO TISSUES
Plastination
Preparation of the specimen:
PREPARATION OF SPECIMEN – INVOLVES FIXATION, HARVESTING, DISSECTING AND SLICING
Platination
Dehydration:
DEHYDRATION – REMOVAL OF WATER AND LIPIDS FROM THE CELLS AND BEING REPLACED BY KETONE OR ALCOHOL
Plastination
Forced impregnation:
FORCED IMPREGNATION – IS THE REPLACEMEMENT OF ACETONE OR ETHANOL FROM THE TISSUE WITH PLASTIC POLMER
Plastination
Curing
CURING – PROCESS OF HARDENING OF THE SPECIMEN AFTER IMPREGNATION
Fixation
point 1:
MOST PLASTINATED SPECIMENS START FROM FIXED MATERIAL AND EVERY ESTABLISHED FIXATION METHOD IS APPLICABLE
Fixation
point 2:
ARTERIALLY INJECTED HUMAN CADAVERS YIELD WELL FIXED ORGANS IN THEIR CORRECT ANATOMICAL POSITION
Fixation
point 3:
HOLLOW ORGANS HAVE TO BE DILATED DURING FIXATION, VERY IMPORTANT IN HEART PLASTINATION
Fixation
point 4:
FIXATION CAN BE OMITTED WHEN USING EPOXY RESIN. EPOXY RESINS HAVE FIXATION PROPERTIES, RESULTING IN BETTER COLOUR PRESERVATION
Why are the processes of dehydration and defatting mandatory?
DEHYDRATING AND DEFATTING ARE MANDATORY SINCE WATER AND LIPIDS CAN NOT BE EXCHANGED DIRECTLY AGAINST POLMERS
Dehydration methods used:
DEHYDRATION METHODS USED :
STEPWISE DEHYDRATION IN GRADED ETHANOL
FREEZE SUBSTITUTION WITH ACETONE
PROPER DEHYDRATION MUST ALWAYS AVOID SHRINKAGE
Forced impregnation
Step 1:
THE IMPORTANT STEP IN PLASTINATION
AFTER DEHYDRATION, THE SPECIMEN IS PLACED IN A POLMER SOLUTIONS
Forced impregnation
Step 2:
THE ACETONE HAS A HIGH VAPOR PRESSURE AND LOW BOILING POINT, WHILE THE POLMER HAS A LOW VAPOR PRESSURE AND HIGH BOILING POINT, WHEN THE VACUUM IS APPLIED THE ACETONE INSIDE IS EXTRACTED OUT AND POLMER INSIDE USING NEGATIVE PRESSURE FORMING BUBBLES IN A SOLUTION
Forced impregnation
Step 3:
THE SPEED OF IMPREGNATION DEPENDS ON THE SPECIMEN AND CLASS OF POLYMER
Curing
When does it commence?
AFTER REMOVAL FROM THE IMPREGNATING BATH, CURING IS CARRIED OUT.
Curing
The three techniques used:
A GAS CURING PROCEDURE IS USED FOR SILICONE SPECIMENS
EPOXY RESIN SPECIMENS TAKE ADVANTAGE OF THE TISSUE AMINES
POLYESTER USES UV LIGHT FOLLOWED BY HEAT TREATMENT
