DARBY EXAM 4 QUESTIONS AND
100% CORRECT ANSWERS
Which of the following modes of disease spread is depicted in this case?
a. Direct contact
b. Indirect contact
c. Droplet infection
d. Airborne infection
D. The mode of disease spread was by airborne infection. Bacterial particles aerosolized in water
vapor were inhaled by the client infecting his lungs.
A. Direct contact involves exposure to bodily tissues/secretions directly with nonintact skin (bare
hands).
B. Indirect contact involves injuries with contaminated sharps and contact with
contaminated surfaces.
C. Droplet infection involves spatter or spray of microbes onto mucous membranes or
nonintact skin.
What is the source of the microbes in this case?
a. Client's oral cavity
b. Hygienist's hands
c. Contaminated instrument
d. Dental unit water
D. The source of the microbes was the pathogens in the dental unit water resulting
from untreated dental unit waterlines.
,A. The microbes did not originate from the client's oral cavity.
B. The hygienist's hands were gloved and not contaminated.
C. The instruments that were used on this client were sterile.
In this case, which of the following infection control procedures likely would
have prevented disease transmission?
a. Using barriers
b. Cleaning the housekeeping surfaces
c. Treating dental unit waterlines
d. Wearing proper PPE
C. Disease transmission would have been prevented by proper treatment and testing of the
dental unit waterlines ensuring that water used in OHC had no more than 200 CFU/mL of
aerobic mesophilic heterotrophic bacteria.
A. Disease spread was by airborne infection and did not involve clinical contact surfaces.
B. Disease spread was by airborne infection and did not involve housekeeping surfaces.
D. Disease spread did not involve microbes from the DHCP
Which of the following microorganism type is responsible for Legionnaires' disease?
a. Bacterium
b. Prion
c. Virus
d. Fungus
A. Legionella bacteria results in legionnaire's disease.
B. The microbe responsible for the disease is not a prion.
, C. The microbe responsible for the disease is not a virus.
D. The microbe responsible for the disease is not a fungus
What was the portal of entry of Legionella into the older adult's body?
a. Breathing in contaminated water vapor
b. Swallowing contaminated water
c. Infiltrating microbes into nonintact mucosa
d. Splashing of droplets on mucous membranes
A. The client aspirated contaminated water vapor during OHC procedures.
B. Swallowing contaminated water would not have resulted in disease acquisition
because legionnaire's disease affects the lungs and is not acquired through the oral-fecal
route. C. Infiltrating microbes onto nonintact mucosa may have caused an oral infection.
D. Exposing mucous membranes to droplet particles would not result in a lung infection
CASE B
After dismissing his last client of the day, Preston Miller, RDH, returns to his treatment
room. He is in a rush because his son's baseball team has a game tonight and he is the
coach. Preston hurriedly closes his instrument cassette, not taking care to arrange the
instruments beforehand. In the instrument processing area, he lifts the cassette off the
metal tray to place it into the ultrasonic unit. Unknowingly an explorer is protruding
from a hole in the cassette and penetrates his finger through the exam glove. He removes
his gloves and sees a small amount of blood forming on his index finger.
Use CASE B to answer #9-15
What should Preston the dental hygienist do next?
a. Scrub the finger using a stiff brush.
100% CORRECT ANSWERS
Which of the following modes of disease spread is depicted in this case?
a. Direct contact
b. Indirect contact
c. Droplet infection
d. Airborne infection
D. The mode of disease spread was by airborne infection. Bacterial particles aerosolized in water
vapor were inhaled by the client infecting his lungs.
A. Direct contact involves exposure to bodily tissues/secretions directly with nonintact skin (bare
hands).
B. Indirect contact involves injuries with contaminated sharps and contact with
contaminated surfaces.
C. Droplet infection involves spatter or spray of microbes onto mucous membranes or
nonintact skin.
What is the source of the microbes in this case?
a. Client's oral cavity
b. Hygienist's hands
c. Contaminated instrument
d. Dental unit water
D. The source of the microbes was the pathogens in the dental unit water resulting
from untreated dental unit waterlines.
,A. The microbes did not originate from the client's oral cavity.
B. The hygienist's hands were gloved and not contaminated.
C. The instruments that were used on this client were sterile.
In this case, which of the following infection control procedures likely would
have prevented disease transmission?
a. Using barriers
b. Cleaning the housekeeping surfaces
c. Treating dental unit waterlines
d. Wearing proper PPE
C. Disease transmission would have been prevented by proper treatment and testing of the
dental unit waterlines ensuring that water used in OHC had no more than 200 CFU/mL of
aerobic mesophilic heterotrophic bacteria.
A. Disease spread was by airborne infection and did not involve clinical contact surfaces.
B. Disease spread was by airborne infection and did not involve housekeeping surfaces.
D. Disease spread did not involve microbes from the DHCP
Which of the following microorganism type is responsible for Legionnaires' disease?
a. Bacterium
b. Prion
c. Virus
d. Fungus
A. Legionella bacteria results in legionnaire's disease.
B. The microbe responsible for the disease is not a prion.
, C. The microbe responsible for the disease is not a virus.
D. The microbe responsible for the disease is not a fungus
What was the portal of entry of Legionella into the older adult's body?
a. Breathing in contaminated water vapor
b. Swallowing contaminated water
c. Infiltrating microbes into nonintact mucosa
d. Splashing of droplets on mucous membranes
A. The client aspirated contaminated water vapor during OHC procedures.
B. Swallowing contaminated water would not have resulted in disease acquisition
because legionnaire's disease affects the lungs and is not acquired through the oral-fecal
route. C. Infiltrating microbes onto nonintact mucosa may have caused an oral infection.
D. Exposing mucous membranes to droplet particles would not result in a lung infection
CASE B
After dismissing his last client of the day, Preston Miller, RDH, returns to his treatment
room. He is in a rush because his son's baseball team has a game tonight and he is the
coach. Preston hurriedly closes his instrument cassette, not taking care to arrange the
instruments beforehand. In the instrument processing area, he lifts the cassette off the
metal tray to place it into the ultrasonic unit. Unknowingly an explorer is protruding
from a hole in the cassette and penetrates his finger through the exam glove. He removes
his gloves and sees a small amount of blood forming on his index finger.
Use CASE B to answer #9-15
What should Preston the dental hygienist do next?
a. Scrub the finger using a stiff brush.
