Laser Exam UPDATED ACTUAL Exam
Questions and CORRECT Answers
Which best characterizes laser waves:
A - Quasichromatic, non-collimated, non-coherent
B - Multichromatic, non-collimated, non-coherent
C - Monochromatic, collimated, coherent - CORRECT ANSWER - C - Monochromatic,
collimated, coherent
A laser pulse cycles between ON for 5 ms and OFF for 20 ms. What is the duty cycle?
A - 10%
B - 20%
C - 25%
D - 40% - CORRECT ANSWER - B - 20%
Which of the following lasers is used on hard tissue?
A - CO2 9,250 nm
B - THOR
C - Nd:YAG 1064nm
D - Diodes 810-1064nm - CORRECT ANSWER - A - CO2 9,250 nm
What is the definition of Power?
,A - Ability to perform work, expressed in joules (J)
B - Amount of work performed per unit time, expressed in watts (W)
C - A measurement of the total amount of time that the pulse is emitted
D - The power of a single, brief emission from a laser programmed for pulsed behavior rather
than continuous operation - CORRECT ANSWER - B - Amount of work performed per
unit time, expressed in watts (W)
When do you test fire a laser?
A - When it is a new laser
B - Always test fire before use
C - Depends on the laser
D - Never - CORRECT ANSWER - B - Always test fire before use
Electromagnetic waves transport energy through
a. Empty Space
b. A material medium
c. Matter
d. Mechanical waves - CORRECT ANSWER - a. Empty Space
Which is not a way lasers interact with tissues?
a. Reflection
b. Transduction
c. Scattering
d. Absorption - CORRECT ANSWER - b. Transduction
Which laser wavelewngths can penetrate to the retina of the eye and cause damage?
, a. Diode wavelengths
b. Er:YAG
c. Nd:YAG
d. BothA&C - CORRECT ANSWER - d. BothA&C
Light-induced fluorescence can be used for
a. Caries detection
b. Mucosal evaluation
c. Pain relief
d. BothA&B - CORRECT ANSWER - d. BothA&B
Continuous wave lasers cause increased char of tissue compared to ultraspeed or superpulse
lasers. Ultraspeed or superpulse lasers cause minimal heat spread compared to continuous wave
lasers.
a. Both statements are true
b. Statement 1 is true; statement 2 is false
c. Both statements are false
d. Statement 1 is false; statement 2 is true - CORRECT ANSWER - a. Both statements are
true
Which of the following is NOT a tissue chromophore that absorbs a laser wavelength?
a. Water
b. Sodium (not at the dental wavelength)
c. Hemoglobin
d. Melanocytes - CORRECT ANSWER - b. Sodium (not at the dental wavelength)
Questions and CORRECT Answers
Which best characterizes laser waves:
A - Quasichromatic, non-collimated, non-coherent
B - Multichromatic, non-collimated, non-coherent
C - Monochromatic, collimated, coherent - CORRECT ANSWER - C - Monochromatic,
collimated, coherent
A laser pulse cycles between ON for 5 ms and OFF for 20 ms. What is the duty cycle?
A - 10%
B - 20%
C - 25%
D - 40% - CORRECT ANSWER - B - 20%
Which of the following lasers is used on hard tissue?
A - CO2 9,250 nm
B - THOR
C - Nd:YAG 1064nm
D - Diodes 810-1064nm - CORRECT ANSWER - A - CO2 9,250 nm
What is the definition of Power?
,A - Ability to perform work, expressed in joules (J)
B - Amount of work performed per unit time, expressed in watts (W)
C - A measurement of the total amount of time that the pulse is emitted
D - The power of a single, brief emission from a laser programmed for pulsed behavior rather
than continuous operation - CORRECT ANSWER - B - Amount of work performed per
unit time, expressed in watts (W)
When do you test fire a laser?
A - When it is a new laser
B - Always test fire before use
C - Depends on the laser
D - Never - CORRECT ANSWER - B - Always test fire before use
Electromagnetic waves transport energy through
a. Empty Space
b. A material medium
c. Matter
d. Mechanical waves - CORRECT ANSWER - a. Empty Space
Which is not a way lasers interact with tissues?
a. Reflection
b. Transduction
c. Scattering
d. Absorption - CORRECT ANSWER - b. Transduction
Which laser wavelewngths can penetrate to the retina of the eye and cause damage?
, a. Diode wavelengths
b. Er:YAG
c. Nd:YAG
d. BothA&C - CORRECT ANSWER - d. BothA&C
Light-induced fluorescence can be used for
a. Caries detection
b. Mucosal evaluation
c. Pain relief
d. BothA&B - CORRECT ANSWER - d. BothA&B
Continuous wave lasers cause increased char of tissue compared to ultraspeed or superpulse
lasers. Ultraspeed or superpulse lasers cause minimal heat spread compared to continuous wave
lasers.
a. Both statements are true
b. Statement 1 is true; statement 2 is false
c. Both statements are false
d. Statement 1 is false; statement 2 is true - CORRECT ANSWER - a. Both statements are
true
Which of the following is NOT a tissue chromophore that absorbs a laser wavelength?
a. Water
b. Sodium (not at the dental wavelength)
c. Hemoglobin
d. Melanocytes - CORRECT ANSWER - b. Sodium (not at the dental wavelength)
