Deck 24: Dental Unit Waterlines

Question 1

The dental office gets its water from _____,and the water then is routed to _____.

A)municipal supplies; sinks, toilets, air conditioners, and the dental unit
B)tanks delivered to the office; sinks, toilets, air conditioners, and the dental unit
C)wells; sinks, toilets, air conditioners, and the dental unit
D)Both a and b are correct.
E)Both a and c are correct.

Answer 1

Both a and c are correct.

Question 2

While using for routine dental procedures,biofilm and bacteria found in water from municipal lines can enter the oral cavity of a patient through:

A)the faucet.
B)the handpiece.
C)the waterline.
D)both b and c

Answer 2

both b and c

Question 3

Which of the following statements is true about dental unit waterlines?

A)Viruses cannot multiply in the DUWL.
B)The use of sterile water in the self-contained water reservoir ensures that water will be sterile at the point of delivery.
C)Microfilters reduce the bacterial contamination of water and destroy the biofilms that colonize the DUWLs.
D)Flushing for 20 to 30 seconds after each patient will remove biofilms from the lines.

Answer 3

Viruses cannot multiply in the DUWL.

Question 4

Waterborne diseases have been found in:

A)hospitals.
B)schools.
C)dental water lines.
D)all of the above.

Question 5

Planktonic bacteria are:

A)unable to survive in DUWLs.
B)prevented from entering DUWLs by use of anti-retraction valves.
C)free floating in the water.
D)in the biofilm attached to DUWL walls.

Question 6

Advantages of using self-contained water reservoirs include:

A)increasing the number of bacteria in waterlines.
B)decreasing the number of bacteria in waterlines.
C)giving the dental office control over quality of water used.
D)all of the above.

Question 7

Factors contributing to the formation of bacteria in DUWLs include all of the following except:

A)stagnant water.
B)water heating.
C)well water.
D)back flow from a saliva ejector.

Question 8

The advantages of self-contained water reservoirs include:

A)they are less expensive to use.
B)dental personnel can select the quality of water used.
C)maintenance of the water system is under the control of the dental staff.
D)both b and c

Question 9

The type of water used during surgery where bone is exposed should be:

A)heated municipal water.
B)distilled water from a self-contained system.
C)only sterile water delivered in a sterile syringe.
D)any type of water can be used.

Question 10

Backflow from low-volume saliva ejectors can occur when a patient:

A)is positioned in a reclined position in the dental chair.
B)closes his or her lips around the tip of a saliva ejector.
C)first turns on the saliva ejector.
D)has been using a saliva ejector for more than 10 minutes.

Question 11

Biofilm can contain many types of bacteria,including _____ protozoa.

A)fungi, algae, and
B)fungi, and algae, but not
C)and fungi, but neither algae nor
D)but not fungi, algae, or

Question 12

To reduce the microbial count temporarily and to help clean the handpiece waterlines,DUWLs should be flushed:

A)for 20 to 30 seconds between patients.
B)every morning for several minutes.
C)every evening for 20 minutes.
D)both a and b

Question 13

Reduction of exposure to the dental unit water for the dental team includes all of the following except:

A)the HVE.
B)a dental dam.
C)masks, protective eyewear, and/or face shields.
D)both a and c

Question 14

The options available for testing the quality of waterline cleaning include:

A)none; there is no availability for testing of the dental waterline cleaning.
B)using a commercial testing service.
C)using an in-office test kit.
D)both b and c

Question 15

Within 5 days of installation,research has shown that microbial counts in new dental unit waterlines can reach _____ CFUs/mL.

A)10
B)500
C)1000
D)200,000

Question 16

When choosing a chemical agent to give dental unit water lines a "shock" treatment,care should be taken to:

A)use a product that will not damage the dental units.
B)check with the manufacturer to determine the recommended chemical product and protocol for maintenance.
C)use a chemical agent no more than once a month.
D)do both a and b

Question 17

The bacteria in the biofilm are more resistant to chemical germicides than planktonic bacteria by a factor of:

A)3.
B)5.
C)100.
D)1500.

Question 18

Methods of reducing the level of bacterial contamination in waterlines include all of the following except:

A)yearly replacement of all water lines.
B)chemical treatment regimens.
C)self-contained water reservoirs.
D)microfiltration.

Question 19

Disposable inline microfiltration cartridges should be replaced:

A)according to the manufacturer's recommendations.
B)between patients.
C)once a week.
D)twice a day.

Question 20

The type of plaque that develops inside DUWLs,consisting of bacterial cells and other microbes,is called:

A)the infective layer.
B)microfilm.
C)biofilm plaque.
D)slime.

Question 21

Flushing the dental waterlines for several minutes at the beginning of the treatment day and for 20 to 30 seconds between patients will help to:

A)reduce prep time.
B)reduce the microbial count.
C)do both a and b
D)do none of the above.

Question 22

Which of the following techniques in dentistry has been proved to cause adverse health effects on patients?

A)Back suction
B)Clogged suction line
C)Backflow from saliva ejector
D)None of the above