Autoclave in Dentistry

1. Autoclave
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2. Introduction
• Sterilization – the use of a physical or chemical
procedure to destroy all microorganisms
including bacterial spores.
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3. • Sterilization procedures are used in a variety
of health-related fields—including dentistry
• In dentistry, a number of techniques have
been developed to deal with the issue of
keeping devices free from microbes.
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4. 4 sterilization methods:
1. Steam pressure sterilization (autoclave)
2. Chemical vapor pressure sterilization -
(chemiclave)
3. Dry heat sterilization (dryclave)
4. Ethylene oxide sterilization
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5. • These are high temperature pressure
chambers that use carefully regulated steam
to sterilize instruments and materials.
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6. • The name comes from
– (Greek) auto = self self-locking device
– (Latin) clavis = key
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7. Advantages
• Rapid and effective
• Effective for sterilizing cloth surgical packs and
towel packs
Disadvantages
• Items sensitive to heat cannot be sterilized
• It tends to corrode carbon steel burs and
instruments
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8. Types of Autoclaves
Downward displacement
Vacuum
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9. Downward displacement
• Also known as Gravity displacement unit.
• This is because of the method of air removal
in the sterilization chamber.
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10. Vacuum
• Steam is created in a second, separate
chamber and held until the proper amount to
displace all of the air in the sterilization
chamber.
• The steam is then released into the
sterilization chamber in a pressurized blast,
forcing the air out through the drain hole and
starting the sterilization process.
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11. • Moist heat coagulates cell proteins of the
microorganisms and thus kills all the living
entities (including spores) in 15 to 20 minutes.
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12. Types of sterilization cycles
Classification Suitable for Processing Used by
N Type (Downward
Displacement)
•Unwrapped solid
instruments for
immediate
use.
S Type (Vacuum) •Suitable for naked and
single wrapped solid and
hollow items.
Medical Surgeries
Podiatrist
Tattooist
Body Pierces
B Type (Vacuum) •Unwrapped & wrapped
solid and hollow
instruments.
•Porous loads,
e.g drapes & gowns.
Dentists
Plastic surgeons
Day surgeries
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13. Three major factors for effective
autoclave:
Pressure: 15psi
Temperature: 121 deg C
Time: 30 mins
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14. High
temperature
High pressure
Shorter
time for
sterilization
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15. Sterilization stages
• Presoaking
• Cleaning
• Lubrication
• Inspection
• Preparation and packing
• Sterilization
• Storage
• Delivery of materials
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16. How to use the Autoclave
• DO NOT OVERFILL THE CHAMBER!
• Load should not touch chamber walls
• DOOR should be clear of obstructions before
closing
• Whenever possible, autoclave the load
immediately after preparation. Do not leave
unprocessed items in the autoclave overnight.
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17. How to know if autoclave is functioning correctly:
• Biological - Tests ability of autoclave to sterilize
effectively - Geoacillus stearothermophilus
spore strips often used because they are
resistant to steam sterilization.
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18. Potential risks
• Autoclaves use high pressure and high
temperature steam for sterilization.
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19. • Heat burns
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20. • Steam burns
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21. • Hot fluid scalds
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22. • Hand and arm injuries when closing the door.
• Body injury if there is an explosion.
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23. Personal Protective Equipment (PPE)
• Heat-insulating gloves - cover hands and
forearms.
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24. • Lab coat.
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25. • Eye protection
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26. • Close toe shoes
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29. References
• Le, R.N., et al (2005), Autoclave Testing in a University Setting.
Applied Biosafety, 10(4), 248-252.
• Centers for Disease Control and Prevention, Oral Health Resources
“Sterilization – Monitoring FAQs,” April 2005.
www.cdc.gov/oralhealth/infectioncontrol/faq/sterilization_monitori
ng.htm
• University of Ottawa Environmental Health and Safety Service, A
Guideline for the Safe Use of Autoclaves, 9 July 2003,
• http://www.uottawa.ca/services/ehss/docs/autoclave.pdf
• 3M™ Technical Information Sheet: 3M™ Comply ™ (SteriGage™
Steam Chemical Integrator, 1999, 70-2009-0710-6 (29.5) DPI
• 3M™ Technical Product Profile: 3M™ ATTEST™ Biological Monitoring
System, 1994
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