How to Use a Dental Autoclave Step-by-Step (Without Damaging Instruments)

You’d be surprised how many dental staff skip key steps — and end up with wet pouches, failed sterilisation cycles, or worse... contaminated instruments marked as “ready to use.”

Let’s break down how to properly use a dental autoclave — whether you’re running a Class B unit or something simpler — so every cycle does what it’s supposed to do.

Why Using an Autoclave Properly Actually Matters

Autoclaves aren’t dishwashers. They’re medical-grade sterilisation units that need:

• Exact temperature
• Correct steam penetration
• And most importantly — proper loading technique

When used wrong, even the most expensive unit can fail a cycle. And guess what? If that happens, you legally can’t use those instruments — even if they “look clean.”

Every missed step is a risk to patients — and your license.

Step-by-Step: How to Use a Dental Autoclave

1. Pre-clean and dry all instruments

Sterilisation doesn’t clean — it kills microbes. If there's debris on your tools, sterilisation won’t work.

• Use ultrasonic cleaners or enzymatic solutions first
• Rinse, dry thoroughly before pouching

 2. Pouch correctly

Use steam-permeable sterilisation pouches with indicators. Seal properly — no overstuffing.

Write:

• Date of sterilisation
• Load ID
• Initials (optional)

 3. Load the autoclave properly

• Lay pouches paper side up
• Don’t overlap pouches or stack trays too tightly
• Use wire mesh racks, not solid shelves
• Leave space for steam to circulate

Never lay pouches flat on the chamber floor — they’ll cook unevenly.

 4. Select the correct cycle

• Use “wrapped” or “porous” settings for pouched instruments
• Class B units should always run a vacuum cycle
• Use the drying phase — it’s not optional

 5. Start the cycle and monitor

• Record the cycle start time and batch ID
• Confirm temperature reached 134°C for 3+ minutes
• If interrupted or error code appears, repeat the cycle — don’t guess

 6. Let it cool — fully

• Don’t rush the drying phase
• Don’t open the door too early
• Instruments must be dry and warm, not hot or damp when removed

 7. Store in a clean, dry environment

• Don’t stack warm pouches — let them sit flat
• Use closed drawers or covered trays
• Keep away from aerosol sprays, damp areas, or sunlight

Common Mistakes That Lead to Failed Sterilisation

• Pouching wet instruments
• Overloading trays
• Skipping the drying phase
• Using tap water instead of distilled
• Not performing daily B&D or Helix tests

Extra Tips for Consistent Results

• Use only distilled or demineralised water
• Perform weekly protein residue tests
• Change chamber filters as per manufacturer instructions
• Keep a sterilisation logbook with every cycle's data

What About Class B vs Class S?

• Class B autoclaves are required in Australia for wrapped instruments and hollow items
• Class S are suitable only for solid, unwrapped loads (or limited uses)

If you’re unsure, always go Class B. Learn more here:

How to Know If Your Cycle Was Successful

Check:

• Chemical indicator has changed colour
• Cycle printout shows correct pressure/time
• Instruments are bone-dry and warm, not damp

If any of those fail — don’t use the load. Resterilise it.