The document discusses the importance of thoroughly evaluating materials before use. It outlines several key aspects of materials evaluation including standard specification tests from national and international organizations, laboratory tests to assess suitability, and extensive clinical trials conducted by manufacturers in cooperation with universities and hospitals prior to general use. Both the success and failures of biomaterials are discussed, noting that while most perform satisfactorily, manufactured devices will always have some failure rate due to human variability.

1. Materials Evaluation

2. Number of available materials increases
More and more important to be protected from
unsuitable products or materials.
Thoroughly evaluate the material
(Most manufacturers of materials operate an extensive quality assurance
program and materials are thoroughly tested before being released to the
general practitioner)
Materials Evaluation -Need

3. Standard Specifications
• Many standard specification tests
– National and international standards organizations (ISO)
which effectively maintain quality levels.
– Such specifications normally give details for
• Testing Of Certain Products
• The Method Of Calculating The Results
• The Minimum Permissible Result, Which Is Acceptable.

4. Laboratory Evaluation
• Laboratory tests
– Used to indicate the suitability of certain
materials.
• It is important that methods used to evaluate
materials in laboratory give results, which can
be correlated with clinical experience.

5. Clinical Trials
• Although laboratory tests can provide many
important and useful data on materials.
• The ultimate test is the controlled clinical trial
and verdict of practitioners after a period of
use in general practice.
• Many materials produce good results in the
laboratory, only to be found lacking when
subjected to clinical use.

6. Clinical Trials
• The majority of manufacturers carry out
extensive clinical trials of new materials,
• Normally in cooperation with a
– University
– Hospital department,
Prior to releasing a product for use by general
practitioners.

7. Success and Failure are seen with
Biomaterials and Medical Devices

8. • Most biomaterials and medical devices
perform
– Satisfactorily,
– Improving the quality of life for the recipient or
– Saving lives.
• Still, man-made constructs are never perfect.
• Manufactured devices have a failure rate.

9. Reason for failure
• Humans Differ from
– genetics,
– gender,
– body chemistries,
– living environment,
– and physical activity.
Furthermore, physicians also differ in their "talent"
for implanting devices.

10. Central issues for the biomaterials
• Scientist
• Manufacturer
• Patient
• Physician
1- what represents good
design;
2- Who should be
responsible when devices
perform with an
inappropriate host response;
3- What is the cost/risk or
cost/benefit ratio for the
implant or therapy?

11. Subjects are Important to
Biomaterials Science

12. Subjects are Important to Biomaterials
Science
• Toxicology
• Biocompatibility
• Functional Tissue Structure
and Pathobiology
• Healing
• Dependence on Specific
Anatomical Sites of
Implantation
• Mechanical and
Performance Requirements
• Industrial Involvement
• Ethics
• Regulation