Instrument Decontamination

The power of enzymatic cleaners

Laura Yates, Technical Manager at dentisan explains the advantages of using an enzymatic detergent to clean reusable dental instruments.

Aims & Objectives

    • To teach readers about the importance of thoroughly cleaning reusable dental instruments
    • To explain the characteristics and advantages of using enzymatic detergents
    • To update readers on the recommended processes for cleaning reusable dental instruments

Learning Outcomes

    • Readers will understand the importance of thoroughly cleaning reusable dental instruments before disinfection
    • Readers will be aware of the characteristics and advantages of using enzymatic detergents
    • Readers will be aware of the recommended processes for cleaning reusable dental instruments

This article relates to GDC development outcome C

Understandably, there has been a lot of emphasis recently on the importance of adequate surface and environmental cleaning and decontamination in dental practices. Whilst this remains a key priority, it is equally vital that thorough and effective instrument cleaning and sterilisation is achieved every day in practice.

This article considers why enzymatic detergents are an effective cleaning solution for reusable dental instruments. It covers the science behind them, their advantages and the recommended process for using them.

The importance of effectively cleaning reusable dental instruments

Biological matter, such as blood, saliva and tissue, must be completely removed from reusable dental instruments as soon as possible after use to ensure they are thoroughly clean and ready for sterilisation.

If biological matter is not removed prior to sterilisation, it will become ‘baked on’ to the instrument during autoclaving, thus rendering the instrument non-sterile and therefore unusable. In addition, tissues contain salts which can cause metal discolouration, and if left long enough, can cause instruments to rust, increasing the risk of mechanical failure and the inevitable cost of repair or replacement.

An enzymatic detergent, which contains no alcohol and uses the natural abilities of enzymes to break down biological matter, is therefore an ideal cleaning agent for reusable dental instruments.

What are enzymatic dental detergents?

Enzymatic detergents gain their cleaning efficacy from enzymes, which are naturally occurring proteins made up from amino acid building blocks. Enzymes are responsible for many essential biochemical reactions in microorganisms, plants, animals and humans. They are crucial to life processes, such as the ‘breaking down’ in the digestive system.

Enzymes catalyse reactions, i.e. they facilitate specific reactions, while at the same time remaining themselves unchanged. This enables reactions (such as breaking down proteins in blood) to take place at lower temperatures and reduces the need for the aggressive chemicals to break down soil.

A considerable proportion of the soiling found on reusable instruments contains proteins that act as binding agents. Particulate dirt can be bound by the coagulation of these proteins on the surface. If the binder proteins can be broken down into smaller molecules, this binding action is destroyed and the bound soil, as well as the protein, can be released from the surface .

Enzymes are selective in terms of the reactions they carry out and will only work on a material if it is present; if no such material is present the enzyme simply does not function. It is this selectivity that not only provides efficient and effective cleaning, but has enabled the formulation of cleaning products that have excellent material compatibility – a particularly important benefit for use in dental surgeries, where many different types of surfaces and materials are found.

A summary of advantages

  1. The presence of enzymes replaces the requirement for harsher chemicals which are used in other non-enzymatic cleaners to break down soil.
  2. Enzymatic cleaners which are pH neutral and alcohol-free can be used at lower temperatures than non-enzymatic cleaners, which are often ineffective at lower temperatures.
  3. The gentler formulations help to preserve dental instruments and are compatible with a wide range of dental surfaces.
  4. The absence of alcohol reduces the likelihood of proteins binding to dental surfaces during cleaning and causing cross-contamination.

Recommended process

Pre-soak

The cleaning process can be severely compromised if contaminants are allowed to dry on to instrument surfaces for any length of time.

HTM01-05 recommends the pre-soaking of instruments, as maintaining a moist and humid atmosphere is an aid to decontamination procedures. Section 3.44 states: “Evidence indicates that keeping instruments moist after use and prior to decontamination improves protein removal and overall decontamination outcomes”.

In fact, research published in a paper by Lipscomb, Pinchin, Collin and Keevil in 2007 found that pre-soaking instruments significantly reduced prion-infected tissue contamination by up to 96%.

HTM01-05 Section 3.5 suggests: “Instruments cleaned as soon as possible after use may be more easily cleaned than those left for a number of hours before reprocessing. Where this is not possible, water immersion or the use of a foam spray or gel intended to maintain a moist or humid environment are thought useful in aiding subsequent decontamination”.

Where instruments cannot be cleaned immediately after use, a pre-treatment spray specifically formulated to keep soiled instruments moist prior to cleaning enables easier removal of protein and debris.

Clean

HTM01-05 Section 3.1 states “The principal methods of cleaning reusable dental instruments currently available are: cleaning using a washer-disinfector; manual combined with ultrasonic cleaning; manual.”

3.30: “Instruments should be briefly immersed in cold water (with detergent) to remove some of the blood and other visible soil before ultrasonic cleaning.” Care should be taken to minimise aerosol production in this process and to safeguard against inoculation injury. The use of a purpose-designed container with sealing lid is recommended.

If using an ultrasonic bath, users should follow the manufacturer’s recommendations for the safe operation of the equipment and take care when loading and unloading.

Furthermore, HTM01-05 says to “change the solution when it becomes heavily contaminated or otherwise at the end of every clinical session, because the build-up of debris will reduce the effectiveness of cleaning. Ensure that staff are aware of the need to assess when a change of solution is necessary as advised in the operational requirements.”

Rinse and inspect

Once cleaned, instruments should be rinsed thoroughly in a sink of clean water and then thoroughly inspected under a magnifying lamp for any sign of remaining contaminants. Only then are the instruments ready for sterilisation.

An enzymatic detergent, which uses the natural abilities of enzymes to break down biological matter and prevent the binding of dirt particulates to the surface – without the use of harsh chemicals and high temperatures – is an ideal choice for the successful cleaning of reusable dental instruments.

Find out more about using enzymatic cleaners by watching our online demo videos.