Instrument Decontamination
Instrument decontamination protocol
Instrument decontamination protocol
Cross infection control is now an essential and legal part of a modern dental practice. When a patient consents to dental treatment they expect the standard of infection control to be impeccable and to put them above any conceivable risk.
Staff have a statutory duty of care to ensure that all instruments and equipment are safe for use and that any that have been contaminated with either blood or other body fluids go through a thorough process of cleaning / disinfection, sterilisation and storage.
This should form part of your written infection control policy, which all staff should understand and abide by at all times. It also forms the basis of a training and reference guide for staff, particularly during their inductions.
It is essential that you implement a systematic approach to this process by having clear "dirty" and "clean" zones in your surgery to limit the cross contamination of used instruments with clean ones. See diagram below:
Wherever possible disposable items should be used. Where it is not practical to use disposable items, instruments and appliances must be processed using the correct procedure. This is the only way of ensuring the equipment is free of any possible contamination and therefore safe to use.
Single use instruments
To reduce the risk of cross-infection, use disposable instruments wherever possible and never reuse.
The use of this symbol means that you should use on a patient during one treatment session and then discard.
It is important that you understand what items are classed as "single-use".
These include;
- Steel burs
- Scalpel blades
- Aspirator tips
- Saliva ejectors
- Matrix bands
- Impression trays
- Plastic cups
- Paper towels
- 3 in 1 tips
- Local anaesthetic needles
- Part-used local anaesthetic cartridges
- Rubber Dam
- Bibs
- Tray Liners
- Gloves
- Polishing disks
- Endodontic instruments
- Used local anaesthetic cartridges
Decontamination process
Pre-sterilisation cleaning
Any instrument contaminated with blood or saliva must be completely clean before it can be sterilised. This process can be via a number of suitable methods as shown later.
Enzyme based:
With manual cleaning considered to be unsuitable, the use of enzyme cleaners is seen by some to be the minimal requirement or "stage 1" of the instrument decontamination process
A suitable method of cleaning / disinfecting instruments prior to using an ultrasonic bath or washer disinfector. In small practices, it is considered to be suitable as a holding solution. Dentists operating domiciliary visits to locations such as prisons may also use this method prior to returning to their practice and using a more systematic and validated process.
Ultrasonic cleaning
Always adhere to the manufacturers instructions for its care and maintenance. The use of an internal tray / basket is preferred and the solution used in the bath must ensure that the instruments are cleaned and disinfected. Avoid interrupting the cycle to enable all instruments to be thoroughly cleaned. Ensure that the unit is empted of water at the end of each day unless more heavily soiled, in which case, emptied more often.
Washer Disinfectors
Considered to be the pinnical of the cleaning process by offering more validated, controlled and efficient process of cleaning instruments then manual cleaning and most ultrasonic baths.
These machines utilise thermal disinfection whilst helping the reduction of bioburden than associated with manual or ultrasonic cleaning. Full automation with lockable doors means that you don’t have to get involved in administering the chemicals at set time periods and that no contaminated instruments can be added part way through a cycle. This ensures a full cleaning process each time for your instruments.
Always consult with a reputable manufacturer on type, requirement, installation etc to ensure you have the right machine and that you and your team fully understand how to gain the most from their use.
Instrument sterilisation
Sterilisation for both types of autoclave (vacuum and non-vacuum) is the same, but the process by which the air is removed is different.
To ensure optimum sterilisation, the autoclave should reach a temperature of 134-137°c for three minutes. Today's autoclaves provide more thorough validation for this process including integral printers or memory cards to aid storage of data.
Effective sterilisation is only achieved when steam condenses on all surfaces of the instruments being autoclaved. This ensures that the instruments are placed to allow free circulation of steam. Never overload the chamber.
Your autoclave should only have cycles set to provide a pre-sterilisation vacuum stage to minimise the possibility of an incorrect cycle being chosen and consequently a load, which has not been fully sterilised.
Vacuum autoclaves (Type B):
These machines displace the air in the sterilisation chamber by pumping out the air then replacing it with steam. This pumping and replacement process is often done twice and therefore the saturation of steam is usually >90%. The high degree of steam saturation makes this type of autoclave suitable for instruments with small lumens in them.
Non-vacuum (type N) autoclaves:
These devices displace the residual air in the chamber by pumping steam into the chamber. This means that the saturation of steam is never 100% in the chamber and residual air always remains in the chamber. Regulatory bodies in the UK suggest that these devices are not suitable for instruments that have small lumen tubes, but concede that they may be useful for hand pieces
Commonly found in practices. If you have one of these, it is essential that you do not wrap instruments prior to autoclaving. Concerns have been raised over the use of these types of autoclaves for instruments containing lumen. If in doubt, always consult your supplier / manufacturers guidelines.
Instrument storage
Sterilised instruments should be stored in clean, dry, covered conditions, such as trays with covered lids.
Sterilised instruments should not be stored in a disinfectant or antiseptic solution.
Pouches are very useful for storing those instruments you use less frequently such as forceps or elevators.
Pouches with a clear side are useful to help you identify those instruments before opening.
Decontamination of instruments prior to repair
You have a statutory duty to ensure that all instruments (& equipment) that leave your surgery have been thoroughly cleaned, disinfected and sterilised prior to being sent for repair. In other words, SAFE. A statement confirming your actions must accompany the instrument / equipment.
If a piece of equipment cannot be sterilised fully, it must be thoroughly cleaned and disinfected in accordance with the manufacturers instructions.
Summary
Instrument disinfection has come a long way in the last 5-10 years, yet our understanding of its importance and the need to communicate the benefits to patients is still very much misunderstood.
Whilst many opinion leaders will argue over key aspects of the decontamination process, few will question the benefits of such a process as your ability to have, manage and effectively promote your infection control policy both internally and externally will reap significant benefits.