Animal biocopatability test

transcript

ANIMAL BIOCOMPATABILITY TEST

Dr. Vigneshwar T I M.D.S

BIOCOMPATIBILITY

The ability of a material to elicit an appropriate biological response in a given application in the body

………Craig

BIOCOMPATIBILITY

HISTORY

A. Late 1800s - first time - patients mouth

B. GV black

C. 1960s - Current philosophy about testing biological properties

BIOCOMPATIBILITY

HISTORY NAZI HUMAN EXPERIMENTATION

SERIES OF MEDCAL EXPERIMENT

JEWS AND ACROSS EUROPE

PRISINORS

BIOCOMPATIBILITY

STANDARDS THAT REGULATES ……..

A. 1926 - First ADA establishment of guideline for Dental Material - the National Bereau of Standard

B. 1933 - Dixon and Rickert - uniform test for all material

C. 1958 - Massler - test on tooth pulp

D. 1959 - Mitchell - test on connective tissue

F. 1972 - ADA Council on DM, instruments and Equipments approved Specification no 41 for Recommended Standard Practice for Biological evaluation of DM

HISTORY

BIOCOMPATIBILITY

HISTORY ISO 10993

ISO 7405 : 1997 Pre clinical evaluation of Biocompatibility of medical devices used in dentistry

ISO 10993-2 Animal welfare requirements

BIOCOMPATIBILITY

HISTORY ISO 10993

ISO 7405 : 1997 Pre clinical evaluation of Biocompatibility of medical devices used in dentistry

ANSI/ADA SPECIFICATION

41-1979

Revised to conform to the ISO standards Reaffirmed - 2001

ISO 10993-2 Animal welfare requirements

BIOCOMPATIBILITY

No of Test

Progress of testing

HISTORY

BIOCOMPATIBILITY

No of Test

Progress of testing

Secondary

Primary

ANSI/ADA SPECIFICATION 41HISTORY

BIOCOMPATIBILITY

Single material may not be biologically acceptable in all situations.

Biocompatibility is Dependant on Biological Responce

Physical Function

BIOCOMPATIBILITY

change in

biological response occurs

when change occurs in

Material itself

Application of Material

BIOCOMPATIBILITY

DEFINING THE

USE OF MATERIAL

BIOCOMPATIBILITY

Consideration for Development of Dental Material :

Strength

Aesthetics

Aspects of Material

Biocompatibility

BIOCOMPATIBILITY

IN VITRO TEST

BIOCOMPATIBILITY

IN VITRO TEST

ANIMAL TEST

BIOCOMPATIBILITY

IN VITRO TEST

ANIMAL TEST

USAGE TEST

ANIMAL BIOCOMPATIBILITY TEST

WHY ANIMALS ?????

To determine the safety of the medical producthow much of a drug or biologic is absorbed into the bloodhow a medical product is broken down chemically in the bodythe toxicity of the product and its breakdown components (metabolites)how quickly the product and its metabolites are excreted from the body

ANIMAL BIOCOMPATIBILITY TEST

ADVANTAGE A. More Comprehensive B. More Relavant

DISADVANTAGE A. Difficult to interpret/control B. Expensive C. Time Consuming D. Ethical Concern E. Paperwork

contact and test site are examined

- control+ control

Test Materialcontact

few weeks

MUCOUS MEMBRANE IRRITATION TEST

WHAT DOES IT CHECK ?

Test material

SKIN SENSITISATION TEST

Test material

Why this test

Freund’s Adjuvent Adhesive patches

Initial injection

hypersensitivity

Patch -> Inflammatory responce

Result Variation

Bases for estimating the allergenicity ?

A. Degree of reaction

B. % of animals thats shows reaction

DECISION POINT APPROACH

Mutagenic/Cariogenic property

Specific order When to stop?

FACTORS AFFECTING

TISSUES

SPECIES

GENDER

OTHER FACTORS

DECISION POINT APPROACH

TYPESLIMITED TIME IN-VIVO

LONG TERM/LIFETIME TEST

subcutaneous tissue

Evaluate the material

IMPLANTATION TEST

USE OF MATERIAL

MUSCLE

IMPLANTATION TEST

A. Connective tissue B. Bone C. Muscle D. Use of Material

IMPLANTATION TEST

A. Use of Material Bone Muscle Connective tissue

MATERIALS THAT CONTACT SOFT TISSUE DIRECTLY

A.ENDODONTIC B.IMPLANTATION C.PERIODONTAL TREATMENT

IMPLANTATION TEST

TYPESSHORT TERM IMPLANTATION

LONG TERM IMPLANTATION

IMPLANTATION TEST

Sheeps

Guinea Pigs

Rabbits

SHORT TERM IMPLANTATION

COMPOUND

test material

control

placed at separate site

remain for 1 - 11 weeks

polyethylene

SHORT TERM IMPLANTATION

allow inflammatory reaction to subside

Reopen implant

Placement of test

material

Area is excised

appropriate

Microscopic examination /Interpretation

Evaluation of Tissue

Response

Histological

Histochemical

Immunohistochemical

LONG TERM IMPLANTATION

COMPOUND

test material

control

placed at separate site

remain for 1 - 2 YEARS

CONCLUSION

REFERRENCE

1. Craig’s - Restorative Dental materials - Twelfth Edition 2. Williams DF. Biocompatibility: an overview. In: Williams

DF, ed. Concise Encyclopaedia of Medical and Dental Materials. Oxford: Pergamon, 1990, pp 51-59.

3. IS0 DIS 7405. Preclinical Evaluation of Biocompatibility of Medical Devices Used in Dentistry, 1994.

4. Schmalz G. Characterisation of a simple dentin barrier test.J Dent Res 1992; 72: 599.

5. Bergenholtz G, Ahlstedt S and Lindhe J. Experimental pulpitis in immunised monkeys. Stand J Dent Res 1977; 85: 396-406.

Animal biocopatability test

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