Dentistry is a meticulous field, so it is essential to understand the answer to the question, ‘what is the difference between disinfection and sterilisation?’ This is to ensure appropriate patient care and prevent the spread of infection. While both processes are essential for cleaning and decontaminating surfaces in dental settings, they are not interchangeable procedures.

Disinfecting at Home

The process of disinfecting removes harmful organisms from objects. This is usually done by applying chemical sprays or wipes. One of the greatest advantages of disinfecting is the availability of products to the general public. It’s possible to find disinfectants in wipe, spray, or other liquid forms, and you can even make your products at home.

Depending on the type of disinfectant used, the product may need to be left on surfaces for as little as 20 minutes or as long as 12 hours. Disinfectants can kill most viruses and fungi, with most commercial products also marketed as effective against the COVID-19 virus when used as directed. While disinfectants can kill bacteria, they may not be able to treat bacterial spores, which lay dormant.

Sanitising at Home

Sanitising is another method of removing dirt and killing germs, often confused with sterilising. While sterilisation eliminates all germs, sanitising aims to lower the amount to a safe level. The process of sanitising can involve both cleaning and disinfecting.

It’s also worth mentioning that while hand sanitisers may not eliminate all germs, they’re good to have on hand until you can access warm water and soap to wash your hands properly.

Can you effectively sterilise at home?

Sterilisation, on the other hand, is a process typically used by professionals in settings such as dental clinics and hospitals.

While disinfecting removes most germs, sterilisation removes all microorganisms — including those that aren’t harmful. Sterilisation is common in medical facilities, but it may also be helpful for businesses and schools that want to get rid of germs in entire rooms.

Methods of sterilisation may include:

pressurised steam (autoclaving)
hydrogen peroxide gas
ethylene oxide (EtO) gas
ionising radiation (typically used for medical equipment)
dry heat cabinets (for medical instruments)
infrared radiation
advanced filtration

Dental Disinfection and Sterilisation

Disinfection

Disinfection is the process of destroying or eliminating most forms of infectious microorganisms on objects or surfaces, but it does not eliminate all microbial life, such as bacterial spores. It can be done with chemical, thermal or ultraviolet light techniques. Common disinfectants for objects such as dental instruments include hydrogen peroxide, chlorine compounds and quaternary ammonia compounds. Because some germs may survive standard disinfectant treatments, so they must be properly cleaned before applying the disinfectant treatment.

Sterilisation

Sterilisation, conversely, is a process of completely destroying all forms of bacteria and other microorganisms on an object or surface so that no viable organisms remain. This includes bacterial spores, which are resistant to regular disinfecting measures. Examples of methods used for sterilisation include autoclaving (steam under pressure), gas sterilisation (ethylene oxide) and dry heat sterilisation (using an oven). These methodologies are typically more time-consuming than simply disinfecting surfaces but provide greater assurance that all germs have been eliminated from the material being treated.

In dental settings, it is important to distinguish between these two processes, as proper cleaning and decontaminating tools and equipment can help reduce potential health risks for dentists and their patients.

What can alter the effectiveness of Sterilisation methods?

The effectiveness of all sterilisation methods can be affected by several factors, including:

The type and number of microorganisms that may be present on the medical device; some organisms are more resistant to the sterilisation process than others
The design of the medical device – microorganisms can be protected by unseen cracks and crevices, which is why cleaning processes must be both thorough and validated; inspection of devices must take into consideration the complex design of some medical devices.
Without a correctly decontaminated device, you will not be able to sterilise a product.

What can you do to Disinfect?

While professionals typically do sterilisation, you can properly disinfect items and common surfaces yourself at home or in your workplace.

Here are some tips for safely disinfecting:

Make sure your product is an actual disinfectant. The manufacturer will indicate such usage on their product labels.
Beware of “natural” products claiming to kill germs. While natural wipes and sprays may be useful for cleaning, they don’t have the germ-eliminating capabilities that chemical disinfectants do.
Learn what the product is designed to kill. Read your disinfectant’s label to find out what kinds of bacteria, fungi, and viruses the product can get rid of. This is especially important if you’re trying to fight coronaviruses like COVID-19.
Let the disinfectant stay on surfaces for the right amount of time. Follow the product’s instructions on the label regarding how long it should sit. Only wipe or wash the disinfectant away if the instructions say so.
Wear gloves. Handling these products could irritate the skin, and contact should be avoided.
Don’t combine chemicals. This is especially true of hydrogen peroxide and bleach.
Safely store your disinfectant products. Put lids and caps back on tightly, and keep all products out of reach of children. Store disinfectants in a cool, dry place, such as a cabinet, and discard them if expired.
Use the disinfectant in a well-ventilated area. This is especially important to do if the product contains bleach.

Ensuring your safety: Infection Control

Infection control in our dental procedures, whether simple treatments or surgery, is not a secret that’s kept from you. You should know what we do, so you can feel reassured. Ask a staff member to show you our sterilisation records, or if you prefer, we can take you on a tour of our steri bay and see what we do to keep you safe. We follow the Australian & NZ Standards 4815, the 4187 Standards and the ADA Guidelines for Infection Control, amongst others. All sterilisation costs are factored into the cost of your treatment.

Monitoring Sterilisation

Sterilisation of dental equipment (e.g. instruments) is critical to ensure our patients are not at risk of having diseases passed from patient to patient. In order to prevent this and protect our patients, we have an infection control program that monitors every stage of the process. Instruments are rinsed and put through a sophisticated cleaner & disinfector. The instruments are then closely inspected and bagged, ready for sterilisation. The handpieces (drills) are disinfected, inspected, dried, and bagged, ready for sterilisation. Most dentists recommend using Melag Autoclave to sterilise their equipment. The steriliser is maintained by a technician every six months, and validation is done annually. It is tested every morning and challenged throughout the day to ensure it is functioning perfectly.

Disinfecting kills most harmful bacteria, viruses, and fungi. Sterilising may be more appropriate for larger commercial settings and medical facilities because it’s guaranteed to get rid of all microorganisms. Professionals always do proper sterilising methods. But you can disinfect surfaces on your own at home and in your workplace. Carefully follow all product directions, and avoid mixing chemicals or using them in nonventilated areas.