clinic theory - unit 3

infection control and disinfection

What is Bioburden?

Blood, saliva, and bodily fluids

What is a primary source of cross-contamination among staff?

When dental staff touch surfaces with contaminated gloves.

A surface in contact with blood, saliva, or other infectious material contains live microorganisms. True or False?

True

What is Contamination?

Objects, barriers or surfaces that have come into contact with microorganisms either directly or indirectly

What is Biofilm?

Consists of bacterial cells and other microbes that adhere to surfaces and form a protective slime layer

Why do we flush our dental units?

Biofilm is a type of plaque that can cause an infection of the water delivery system

• may contain bacteria, fungi, algae, and protozoa

• bacteria in biofilm (slime layer) is hard to remove

What are Critical Instruments?

Items used to penetrate soft tissue or contact bone (not including enamel)

→ ANYTHING THAT GOES SUBGINGIVAL!

• greatest risk of transmitting infection

• needs to be sterilized by heat

• examples: forcepts, scalpels

What are Semi-Critical Instruments?

Things that contact within the mouth, but not subgingival

• lower risk of transmission

• should be sterilized/high-levelled disfinfected

• examples: HVE tips, amalgam carriers, mouth mirror

What are Non-Critical Instruments?

Contact only the skin, no exposure to blood, blood contaminated saliva or tissues

• least risk of transmission

• cleaned & processed with intermediate/low level disinfectant each use

• examples: lead apron, blood pressure cuff

What is Sanitation? (Cleaning)

Removes visible debris, blood, and saliva from an instrument or surface

• Reduces the number of microorganisms and bioburden

• Done before sterilization and disinfection

What is Disinfection?

The destruction of some, but not all (disease-causing) micro-organisms after cleaning/sanitation

Spores are killed during disinfection procedures. True or False?

False, spores still remain

What is Sterilization?

The destruction of all life forms including bacterial spores, viruses, bacteria & fungi

• ***cannot occur through attached debris or blood***

There is such thing as partial or extra sterilizing. True or False?

False. Sterilization is a definite state: Sterile or not sterile.

What is Precleaning?

To clean before disinfecting

What can be used for cleaning?

Soap and water or a cleaner-disinfectant

Why must surfaces be cleaned even without visible blood?

Even a thin layer of saliva can reduce disinfectant effectiveness

What does Precleaning remove?

Bioburden

What type of disinfectant must dental offices use?

EPA-approved hospital-level disinfectant

What does high-level disinfection destroy?

Kills some, but not all bacterial endospores

→ (strongest)

What is high-level disinfection used for?

Disinfecting semicritical items that cannot tolerate heat sterilization

Does high-level disinfection inactivate TB? Yes or No?

Yes

What does intermediate-level disinfection kill?

TB and less resistant microorganisms such as bacteria, viruses, and fungi

→ (2nd strongest)

Does intermediate-level disinfection inactivate TB?

Yes

What is intermediate disinfection used for?

Disinfecting non-critical items or surfaces that have been contaminated with blood or saliva

Where are intermediate disinfections commonly used?

Dental operatory surfaces

When is low-level disinfection used?

On surfaces NOT contaminated with blood

Does low-level disinfection kill TB?

No

Where is low-level disinfection used?

Dental office for general housekeeping (floors and walls)

What does non-tuberculocidal mean?

Does not kill TB

How can instruments be manually cleaned?

Scrubbing with a stiff-bristled brush under running water

What machines are commonly used to clean instruments?

Ultrasonic cleaners or automated washers

When must instruments be cleaned?

Before sterilization

How long must Optim 33 stay wet to kill TB?

Must remain wet for 1 minute

How long must disinfectant stay on surfaces?

Follow the manufacturer's instructions

Identify Qualities of an Ideal Surface Disinfectant

• **Must kill TB and viruses (be virucidal)

• Registered with EPA (environmental protection agency)

• Have DIN (drug identification number)

• Rapidly kill bacteria

• Have residual activity

• Minimal toxicity

Discuss Advantages and Disadvantages of Iodophors

Advantages:

• Effective in 5–10 minutes.

• Intermediate-level disinfectant EPA registered

Disadvantages:

• Can corrode or stain surfaces due to Iodine

• May irritate tissues

• Hard water makes them ineffective.

Discuss Advantages and Disadvantages of Synthetic Phenol Compounds

Advantages:

• EPA registered intermediate-level disinfectant

• Broad spectrum

Disadvantages:

• Leaves a film/residue on surfaces.

• Some must be prepared daily.

Discuss Advantages and Disadvantages of Sodium Hypochlorite

Advantages:

• Fast-acting.

• Inexpensive.

• Broad-spectrum.

• Intermediate-level

Disadvantages:

• Needs daily preparation.

• Strong smell and corrosive

• Irritates skin and eyes.

• No longer recommended or EPA-approved

Discuss Disadvantages of Alcohol

Disadvantages:

• Not effective when blood, saliva or debris are present.

• ^^Evaporates too quickly to disinfect properly.

• Not recommended for surface disinfection.

Discuss Advantages and Disadvantages of Quaternary Ammonia (like lysol)

Advantages:

• Broad-spectrum.

• Low toxicity.

• Effective in 6–10 minutes.

Disadvantages:

• Inactivated by organic matter.

• Inactivated by certain detergents.

• Can damage some materials.

Discuss Advantages and Disadvantages of Chlorine Dioxide

Advantages:

• High-level disinfectant

• Fast-acting surface disinfectant (3 minutes).

• Can act as a chemical sterilant (6 hours).

Disadvantages:

• Does not penetrate debris easily

• Corrosive to aluminum containers

Discuss Advantages and Disadvantages of Glutaraldehyde

Advantages:

• High-level disinfectant.

• Can sterilize.

• Used for plastic items that cannot tolerate heat sterilization.

Disadvantages:

• Very toxic.

• NOT APPROVED FOR STERILIZATION IN DENTAL OFFICES IN CANADA

Discuss Advantages of Accelerated hydrogen peroxide (AHP) aka OPTIM

Advantages:

• Tuberculocidal

• Effective in 1 minute

• Kills many variety of microorganisms

What are the three clinical contact surfaces?

1. Touch surfaces

2. Transfer surfaces

3. Splash, splatter and droplet surfaces

What are Touch Surfaces and some examples?

Are directly touched

• Dental light handles, computers, drawer handles, telephones, pens

What are Transfer Surfaces and some examples?

Touched by contaminated instruments

• Trays, handpiece holders

What are Splash, Splatter and Droplet Surfaces and some examples?

Don’t contact staff or contaminated instruments

• Counter tops

How often are Touched and Transfer surfaces cleaned?

Barrier protected OR cleaned and disinfected BETWEEN CLIENTS

How often are Splash, Splatter and Droplet surfaces cleaned?

At least once daily

What is the purpose of surface barriers?

Prevent contamination of surfaces

• Come in plastic bag or sticky tape form

What should surface barriers be resistant to?

Fluids

When should barriers be removed?

Between clients, while wearing gloves

When should surface barriers be used?

When surfaces are hard to clean and disinfect.

What is the purpose of single-use disposable items?

Reduce contamination between clients