1. STRILIZATION AND DISINFECTION IN A DENTAL CLINIC
Dr. Shahzadi Tayyaba Hashmi

2. STERILIZATION:
The complete removal or destruction of all forms of microbial life including bacterial spores
The use of physical or chemical procedures to destroy all microbial life, including large number of highly resistant bacterial spores
Uses:
Reduce chances of contamination by instruments

4. DISINFECTION:
The procedure intended to reduce microorganisms as far as possible ( but not bacterial spores) by physical or chemical means
The use of physical or chemical procedures to eliminate pathogenic organisms on inanimate objects

5. CATEGORIES OF DENTAL INSTRUMENTS
Critical:
(Penetrates soft tissues, contact bones, or enters into the bloodstream. E.g surgical instruments, periodontal scalars and endodontic files)
Should be sterilized
Semi critical:
(Contacts mucous membrane but do not penetrate into soft tissues or enter into blood stream. E.g Dental mirror, amalgam condenser and dental hand pieces)
Non critical:
Contacts intact skin and need to be disinfected only

6. INSTRUMENTS PREPARATION BEFORE STERILIZATION
Cleaning
Instruments manual washing
Packing or wrapping in plastic bags and sealed

7. TYPES OF STERILIZATION:
Steam sterilization ( autoclave)
Chemical vapor pressure sterilization (Chemiclave)
Dry heat sterilization
Glass bead sterilization for
Endodontic instruments (reamers, files)
Others
Exposure to ethylene oxide gas
Ionizing radiations
Boiling water

8. 1. STEAM STERILIZATION (AUTOCLAVE):
It is a process in which steam is applied to kill the pathogens
Usually 15 psi pressure is applied which increases the boiling point to 121 degree centigrade
Steam at this temperature may destroy all the known pathogens and their spores within 15 minutes
Most effective method of sterilization
Surgical instruments can also be sterilized

9. 2. CHEMICAL VAPOR PRESSURE STERILIZATION
Sterilization by chemical vapor such as formaldehyde under pressure
131 degree centigrade at 20 psi pressure cycle for minutes
Corrosion sensitive burs can be sterilized

10. 3. DRY HEAT STERILIZATION
Effective and safe for metal instruments because this process does not dull instruments edges or cause corrosion
Disadvantage: Less reliable than autoclave

11. DISINFECTION:
Everything which is touched by the operator and assistant and which is in close proximity to the operative field, which cannot be sterilized must be disinfected by scrubbing
Instrument tray, handles of light and operating buttons must be disinfected
Disinfection can be achieved by boiling water, formaldehyde, sodium hypochlorite and alkaline glutar aldehyde