Answers
1.1. During a photothermal reaction, which of the following is true?
a. pulsed laser light is converted into acoustic energy in the form of a
shock wave or high-pressure wave
b. chemical bonds in the molecules that comprise tissue are broken
directly by laser light
c. light-absorbing molecules produce singlet oxygen
d. there is a rise in tissue temperature as light is absorbed
Answer d. there is a rise in tissue temperature as light is absorbed
2.2. Absorbance of laser energy in tissue depends on the?
a. rate of temperature rise of the target tissue
b. delivery system of the laser
c. energy density in the target tissue
d. wavelength of the laser being used
Answer d. wavelength of the laser being used
3.3. AVERAGE POWER equals PEAK POWER for a
a. free-running pulsed laser
b. mode-locked laser
c. laser operating in continuous-wave mode
d. continuous-wave laser operating in super pulse mode
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,Answer c. laser operating in continuous-wave mode
4.4. A CO2 continuous-wave laser used at 5W for 10seconds has a peak
power of
a. 0.5W
b. 5.0 W
c. 50 W
d. 500 W
Answer b. 5.0 W
5.5. Which of the following statements is true?
a. lasers ionize target tissues and make them less susceptible to
subsequent photonic interactions
b. mechanical energy of the photon striking the target tissue reduces
cellular size
c. lasers selectively remove inorganic cellular component through
photostim- ulation
d. thermal energy vaporizes the target tissue by rapidly boiling away inter-
and intracellular fluid
Answer d. thermal energy vaporizes the target tissue by rapidly boiling
away inter- and intracellular fluid
6.6. Thermal relaxation is
a. the heating time during successive laser energy exposures
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, b. unaffected by use of high-volume evacuation
c. dependent on the wavelength of laser used
d. time required for heat to conduct away from a directly heated tissue region-
Answer d. time required for heat to conduct away from a directly heated
tissue region
7.7. Keeping power, repetition rate and exposure time constant, and
changing only fiber diameter from 320 micrometers to 200 micrometers, the
energy density at the end of the fiber
a. remains constant
b. decreases
c. increases
d. initially decreases, then remains constant
Answer c. increases
8.8. Proper disposal/sterilization of used supplies is essential in safe
laser practice. Which of the following should not be used or accomplished
when using a bare fiber delivery system?
a. place cleaved fiber into sharps container
b. dispose of plastic cannula disposed in hazardous waste
c. wipe soft tissue fiber with surface decontaminate
d. autoclave external handpiece
Answer c. wipe soft tissue fiber with surface decontaminate
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