What temperature should a dental autoclave be?

Key Temperature Considerations for Dental Autoclaves

▸Core Purpose: Sufficient Heat is Essential

The core task of a dental autoclave is to thoroughly eliminate all microorganisms from tools using high-pressure steam, including even the most stubborn bacterial spores.
To achieve this, the temperature inside the autoclave must be significantly higher than that of ordinary boiling water. Imagine the principle behind a pressure cooker; the pressure inside makes the steam extremely hot.

▸Pressure is Key

The autoclave heats water to produce steam and then locks it in, preventing it from escaping.
The pressure inside the autoclave continuously increases, essentially "pressurizing" the steam. The greater the pressure, the higher the temperature the steam can reach, far exceeding the temperature achievable by boiling water at home (100°C / 212°F). This high-temperature, high-pressure steam is crucial for truly killing all bacteria and viruses.

▸A "Golden Temperature Range"

Through long-term practice, the dental industry has identified a universally accepted and effective temperature range for sterilization.
This temperature range is proven to ensure safe and reliable sterilization while also:
Being Fast Enough: Completing the work within a reasonable timeframe.
Sufficiently safe: It won't easily damage dental instruments (depending on the instrument itself).
Strong penetration: It allows steam to penetrate the gaps in the packaging material and the interior of the instrument (such as the tubing in a dental handpiece).

▸Temperature isn't a one-size-fits-all approach

While there's a standard range, specific settings may vary slightly:
Instrument type: Highly heat-resistant metal instruments (such as extraction forceps and scaling tips) can withstand the higher end of this range. More delicate instruments or those with plastic/rubber parts (such as dental handpieces and suction tubes) may use slightly lower temperatures within this range, or a specially designed gentle sterilization program to protect them from burns.
Packaging: Instruments wrapped in sterile bags or paper need to ensure that steam can penetrate the packaging material to kill bacteria inside; this is also taken into account in the program settings.

▸Auto-controlled autoclave

Modern dental autoclaves are fully automatic. Once you select the appropriate program (e.g., "General Instruments," "Mobile Phone," "Packaged"), the sterilizer automatically adjusts its heating power, pressure, and duration to ensure the internal temperature reaches and remains stable at the target temperature for a sufficient period (sterilization hold time) for thorough sterilization.
The sterilizer contains a temperature sensor that monitors the temperature in real time, like a thermometer, ensuring it remains within a safe and effective range.

▸How do you know if the temperature is sufficient?

Chemical indicator strips: These are small strips of paper or color-changing blocks attached to the outside of the sterilization bag. If the sterilization process (including reaching and maintaining a sufficient temperature for a sufficient time) is successful, they will change color (e.g., the stripe turns black), indicating that it is "hot enough and long enough."
Biological testing (spore test): A test performed periodically (e.g., monthly). Spores of a particularly difficult-to-kill bacterium are sterilized in the sterilizer and then cultured. If no bacteria grow after culturing, it proves that the temperature (and other conditions) of the sterilizer at that time were sufficient to kill even the most resilient microorganisms.