from A to Z

Dental glossary on sterilisation

To understand and manage sterilisation in the dental practice

Sterilisation is a process of fundamental importance in any dental practice.

This is why all the operators involved must be aware of specific definitions and practices, so as to properly understand and implement all the procedures established by regulations and standards.

Euronda’s sterilisation glossary is a small A to Z guide aimed at dentists and dental assistants, concise yet exhaustive.



Mixture of gasses and vapours that make up the earth’s atmosphere. It must be removed from the sterilisation chamber via a fractionated vacuum pump to enable the thermal energy of the saturated steam to effectively sterilise the surface of instruments directly, or to penetrate loaded packs.


Absence of any type of micro-organism, achieved by carrying out the sterilisation procedure.
Assenza di qualsiasi tipo di microrganismo, ottenuto attraverso il processo di sterilizzazione.
To find out more, read our article: The sterile field in dental surgery


Chemical suitable for living tissue, which prevents contaminating bacteria from developing.
Sostanza chimica adatta ai tessuti viventi, capace di inibire lo sviluppo di contaminanti batterici.


Medical device that uses steam to sterilise tools. Pre-determined temperatures and pressure levels are key parameters maintained over a set period of time.
To find out more, read our articleDifferent types of autoclave

(Medical) Authorisation

Mandatory for initiating and carrying out medical activities. This authorisation is issued by Public Bodies after it is ascertained that an individual has satisfied specific sector requirements.

(Corrective) Action

Action taken to remove a recognised cause of non-compliance.



Preventing bacterial strains from growing and developing by inhibiting or stopping the multiplication of bacteria.


Related to bacteriostasis, i.e. preventing bacteria from growing without actually killing organisms.


Chemical or physical substance that destroys bacteria, fungus and viruses.


Microbial load present on a product or in an environment before sterilisation.
To find out more, read our article: Treating instruments in the dental practice

Bowie & Dick Test

Steam-penetration test carried out to ensure that steam effectively penetrates porous material.
Required by standard EN ISO 17665-1
Simulates a porous load (sheets used in compliance with standard 13060 section 8.6.1)
To find out more, read our article: Bowie & Dick tests: legal requirements



Documented procedures demonstrating the validity of the sterilisation process.

Check (Visual check of load)

Necessary step to prevent dirty defective or eroded tools from being processed. Visual checks are carried out after manual and/or mechanical washing, after drying, and before packaging.

Check (Seal check)

The stability of the sealing strip is checked by verifying the sealing temperature, sealing area width and seal resistance. This is not a temperature check. This procedure instead ensures that sterilisation pouches and rolls are properly sealed, and any sealing irregularities and temperature defects become clear through a simple visual check.


Mechanical action of removing dirt from objects, surfaces, tools, skin and mucous membranes using water and detergent. The aim is to remove micro-organisms, not to inactivate or kill them. If carried out properly, it can remove up to 80% of the microbial load. Synonym: cleansing.

Corrective action

Action taken to remove a recognised cause of non-compliance.


Automatic sequence of operational steps carried out in a sterilisation machine when sterilising equipment. Pre-determined pressure and temperature levels are maintained for a set period of time during the sterilisation cycle (UNI EN 13060)

  • Cycle B: 134°C – Cycle for B-type loads (type A + B hollow instruments, solid items, porous items, wrapped objects). During the 134°C B cycle, the B-type load is exposed to saturated steam for 4 minutes (holding time). The entire 134°C B cycle lasts from 20 to 52 minutes.
  •  Cycle B: 121°C – Cycle for B-type loads (type A + B hollow instruments, solid items, porous items, wrapped objects). During the 121°C B cycle, the load is exposed to saturated steam for 15 minutes (holding time), in accordance with standard 13060. The duration of the 121°C B cycle varies from approximately 20 to 35 minutes, depending on the weight of the load.
  •  Prion Cycle – Cycle for B-type loads (type A + B hollow instruments, solid items, porous items, wrapped objects) deemed contaminated with prions. During the 134°C B-type Prion cycle, the load is exposed to saturated steam for 18 minutes (holding time). The 134°C B cycle lasts from approximately 35 to 45 minutes.



Compulsory procedure that protects professionals and makes tools safe for operators, who must use PPE when handling them during cleaning/cleansing procedures (MD 28/09/1990).


Mixture of chemical substances in powder or liquid form, which reduce the tension between the surface being cleaned and dirt, making it easier to remove.



The act of removing water or moisture from a surface or body. Integral part of the sterilisation process.


A chemical substance capable of killing, inactivating or reducing the quantity of micro-organisms present (bacteria, viruses, fungi and protozoa) by at least one hundred thousand times. Disinfectants are classified as low-, medium- or high-level.


EEC Directive

European Directive that is obligatory and legally binding.



Substance that kills fungus, both on living tissue and non-living matter.



Substance able to kill germs. 


Conduct recommendations, drawn up following a systematic review of the available literature on the subject in question.

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