Cross contamination, also referred as cross infection which implies transfer of bacteria or other contaminants from one surface, substance or subject to another because of unsanitary or unhygienic handling procedures. It is a spread of microorganisms from one source to another. It can occur by direct contact with microorganisms from patient to patient or patient to dentist and vice versa. Also, contamination can occur by indirect contact with contaminated objects or from infected utilities to patients and dental health-care personnel. Some of the main infection sources are patient saliva, blood, and other fluids presenting themselves during dental treatments.

One of the greatest challenges for any dental clinic is to limit cross-contamination among dentists, hygienists, office workers, and patients. Preventing the spread of infection is a must, since the risk of cross-contamination begins when the first patient walks through the front door and continues throughout the day, impacting every surface from the pen in the waiting room to the dental chair in the operatory.

Below are some standard precautions of infection control, which can help you prevent cross-contamination:

1. Sterilisation and disinfection of dental instruments: Sterilisation is aimed at the complete removal of viable organisms, including bacterial spores.

2. Safe storage: Do not store dental supplies and instruments under sinks or in other locations where they might become wet. It is recommended to store sterile and single-use (disposable) instruments in an enclosed drawer or cabinet to ensure complete protection.

3. Hand Hygiene:  Hands can be a major source of cross-contamination. All dental staff members should wash their hands throughout the day using an anti-microbial soap. Sinks with automatic sensors or foot control for turning water on and off are ideal. If not available, it is best to ensure that cross-contamination will not occur after hands are washed.

4. Surface Disinfection: It is a requirement to clean and disinfect any surface that comes into contact with potentially infectious materials. An EPA-approved chemical agent or a surface disinfectant is ideal for removing any contaminant and keeping the area clean. Wiping the surface with a clean towel after disinfecting is also necessary to prevent germ transmission.

5. Personal Protective Equipment: Wearing personal protective equipment (PPE) is a way to reduce the risk of transmission of infectious agents. Dental practitioners and clinical support staff should have protective equipment, and must be educated about how to use or wear the items correctly. Gloves, masks, eye protection, and protective clothing can put a barrier between you and the bacteria.

6. Aseptic Technique: The main goal of aseptic technique is to prevent pathogenic organisms from being introduced to body parts, surfaces, or equipment. It protects patients during invasive dental procedures by using infection prevention measures that reduce the presence of microorganisms. This includes using sterile gloves for oral surgery procedures, including tying back and covering long hair, and covering beards.

7. Waste Disposal: Any human tissue, blood or bodily fluids, as well as any swabs, dressings, drugs or other potentially infectious material should be disposed of separately from normal trash and labelled as biohazardous.

8. Waterline Maintenance: Staff should drain systems each day to prevent accumulation of biofilms and protect the integrity of water used for rinsing and cleansing.