1. Dental Assisting DNT 354 (Sterilization)
By Dr. Kifaya Ifthikar

2. Contents Sterilization Importance of sterilization
3) Success of sterilization
4)Methods of Sterilization

3. Sterilization
It’s a process effectively kill or eliminates all forms of living micro organisms including spores. By physical & Chemical methods Importance of sterilizations >Most important method of infection control in the dental office >Effective microbial kill with minimal instrument damage >Best method for Dental instrument sterilization

4. Success of sterilization
>Properly clean the dental instrument
before sterilization.
Devide the patient care devices
according to the risk of infection
>Do not overload the sterilizer punch
can occur in the rapped packs
>Do not remove the instruments prior
to completion of the cycle
>Proper storage of the instruments
in a closed dry cabinet

5. >Regularly clean & maintain the sterilizer
>Monitoring the sterilization
>Indicators can be used to monitor
>External indicators printed
on the packing materials
4) Method of Sterilization
1)Physical Methods
a)Dry Heat
Widely used method& non corrosive
Reliable method
Can only apply for thermoplastic materials
Dry Heat ( c) One hour exposure time& good penetrability
Much lower time exposure required to kill the microbes
Hot air oven( iol,fats,metal surgical instruments)

6. b) Incineration ; Excellent method of destroying materials
b) Incineration ; Excellent method of destroying materials. Materials are reduced to ashes by burning
>Contaminated clothes >Pathological materials >Beddings c) Filtration >Does not destroy the microorganism only remove them. >Sterilize sera ,sugars & Antibiotic solution >Sieving >Purification of water

7. >
b)Moist Heat >Act as Steam under pressure( for mints) >Kill microorganisms by coagulating proteins. >Ability to processes a wide range of materials >Rapid & effective >Most economical method of Sterilization. Autoclave

8. 2)Methods of Radiation; Used on material that cannot be Sterilized by heat or chemicals
a)Non Ionizing
>Ultra violet rays & Infra red rays
Poor energy , less penetration & hazardous
>Surface Sterilization for aseptic work area.
Sterilization of pre packed items
b)Ionizing
>X- rays
>Gamma Rays
>Very effective method due to high penetrating power
Commercial use, for sterilization of disposable items
Antibiotics & Hormones
Articles should be in dry states
>Very expensive

9. Chemical methods;1 >Wide spectrum of activity
>Speed action
>High penetrating power
>Not corrode the metal
>Not cause local irritation
>Cheap & safety
>Mode of Action: Disruption of cell membrane.
>Protein coagulation
a)Alcohol
-Ethanol/ Isopropyl alcohol
-Frequently used
-No action on spores
-Disinfection of clinical thermometers
b)Formaldehydes :Bactericidal &Sporicidal
-Lethal effect on viruses
-Preserve anatomical specimens .

10. c) Gulutaraldehyde :Effect against Tubercle bacilli , Fungi & viruses
>Sterilization of endoscopes & surgical instruments d)Phenol >Powerful microbial substance >Toxic & corrosive >Disinfect surgical instruments ,contaminated materials and floor Gases Ethylene Oxide >Highly penetrating gas oxide >Effective against all types of viruses & spores . > Sterilization of lung machines , respirator, artificial heart valves Operation theater, Glasses