Hazard definition
the actual contact with or entrance into a living system of the toxic age
toxic give hazerdous to patient?
no - not always if we can manage it
toxicity description
most in dentistry are toxic - yet we dont cause the hazerdous effects
three stages of biological tests for dental materials
- initial tests
- secondary tests
- usage tests
Breakdown of cytotoxicity tests
4 types
- cell attachment and growth
- membrane permeability
- metabolic activity
- Systemic toxicity test
if see hazerdous effect in step one cytoxicity test?
does not go onto the secondary testing
2 examples of tests used for cell membrane permeability
- 51 Cr release assay
- chromium release assay - neutral red release assay
if material is hazerdous what is the effect on permeability
permeability will INCREASE
- can pass through cell membranes
test more used to test cell membrane permeability
neutral red release assay
neutral red release assay
general description of healthy cell vs injured cell
Healthy cell
- stained pink / red with the neutral red and has INTACT MEMBRANE
WHEN ADD THE MATERIAL TO TEST
IF INJURED CELL? –> permeable membrane and no longer see the pink/ red staining as it is LEACHED OUT
