endo-sterilization

2. Clean: Absence of all matter in which micro-org.
may find a favourable condition for growth.
Contamination: Presence of an infectious agent.
(m-organism capable of producing disease)
Terminology

3. Germicide: Causing death of micro-organism.
Bactericidal: Causing the death of bacteria.
Bacteriostatic: Inhibition of bacterial growth
Terminology

4. Disinfection: Destruction of pathogenic agents.
( < than sterilization )
Sterilization: Destruction of all forms of life.
Terminology

5. Objectives of infection control
Never introduce microbesNever introduce microbes into the root
canal system during endo. ttt.
Decrease the N. of existing microbesDecrease the N. of existing microbes to
that normal body resistance can prevent
infection.
Prevent cross-infectionPrevent cross-infection disease.

6. Cleaning
Disinfection
Sterilization

7.  Is 1st
step where debris can be
mechanical removed
How ?
1- Instruments should be wiped in
alcohol immediately.
Cleaning

8. 2- Scrubbing gross debris on instrument with
detergent in warm water using a BRUSH.
Ordinary Soap..............? alkaline film
3- An Ultrasonic Cleaner
can be used in addition to
hand scrubbing.

9. A-Chemical solutions:
B-Boiling and steam:
DisinfectionDisinfection

10. A-Chemical solutions:
For thermo labile materials Gutta-Percha
Soln. Glutraldehyde, Iodophors Soln, → HIV & HBV.
o Conc. changed regularly, in closed container
o Disinfectant cycle starts, the addition of
contaminated instruments would disrupt the
procedure.
o Corrosion of instruments & Pt. sensitivity
Surface disinf. by NaOCL, Alcohols, Ammonium cop.

11. B-Boiling and steam:
 Not capable of destroying all bacteria
and spores and inefficient against
Hepatitis virus.
 They can not be used for sterilization.

12. 1-Autoclaving
2- Dry heat
3-Chemical vapour
4-Ethylene oxide gas
5- Salt (Glass) bead Sterilizers
6- Flaming
SterilizationSterilization

13. 1- Autoclaving:
 special closed system
 100% steam
 Pressure 1-2.15 bar.
 Temp. 121-134 °C
 Time: 3-30 min.

14. Autoclaving
The disadvantageThe disadvantage (pressurized steam) are
- Erosion of glass surface;
- corrosive effect on sharp metal instruments,
- Not suitable for paper, oils, powders and cotton

15. 2- Dry heat:
 At 160 °C for 60-90 min.
 suitable for sharp
instruments, paper points,
oils, and powders.
 it is less effective for handpieces and rubber.

16. 3- Chemical vapour
*Formaldehyde and alcohol with heat and pressure.
*Temp: 137 °C under 1-1.5 bar pressure
*It is effective in killing all organisms
* The corrosion is eliminated
*. Slightly longer times than the autoclaves.

17. 4- Ethylene oxide gas:
 For heat labile materials .Powders, plastics,
delicate sharp instruments, motors &
hand-pieces
 Conc.: 450 mg/litre.
 Temp: 60 °C is used
 Time: several hours
Porous materials absorb some of the gas.

18. 5- Salt (Glass) bead Sterilizers:
This method is rapid & on bracket T. & just
before RCT., not affect the sharp cutting edge
At 218 °C for 5-10 sec
Used to sterilize:
 Instrument’s tips.
 files
 Silver cones & Paper points
 cotton pellets (will chare off if kept
in the sterilizer too long).

19. 6- Flaming:
 Effective only at actually touches.
 Ruin the cutting edge of the instruments.
 Nowadays, not commonly used.