Please answer all of the questions in the quiz below.
1. Soft tissue scattering coefficient is greatest around this wavelength:1,000 nm 3,000 nm 10,000 nm Hint – see 3rd paragraph on the Laser Surgery Basics page
2. Soft tissue absorption coefficient is lowest around this wavelength:1,000 nm 3,000 nm 10,000 nm Hint – see Figure 1 on the Laser Surgery Basics page
3. Soft tissue absorption coefficient is greatest around this wavelength:1,000 nm 3,000 nm 10,000 nm Hint – see Figure 1 on the Laser Surgery Basics page
4. Soft tissue photo-thermal ablation threshold is highest around this wavelength:1,000 nm 3,000 nm 10,000 nm Hint – see Figure 9 on the Laser Surgery Basics page
5. Soft tissue thermal relaxation time is greatest around this wavelength:1,000 nm 3,000 nm 10,000 nm Hint – see Figure 7 on the Laser Surgery Basics page
6. Soft tissue thermal relaxation time is shortest around this wavelength:1,000 nm 3,000 nm 10,000 nm Hint – see Figure 7 on the Laser Surgery Basics page
7. Soft tissue blood vessel capillary diameters are:> 1 mm < 0.01 mm Approx 0.02 - 0.04 mm Hint – see Figure 11 on the Laser Surgery Basics page
8. Soft tissue depth of photo-thermal coagulation / hemostasis is greatest around this wavelength:1,000 nm 3,000 nm 10,000 nm Hint – see Figure 11 on the Laser Surgery Basics page
9. Soft tissue depth of photo-thermal coagulation / hemostasis is shortest around this wavelength:1,000 nm 3,000 nm 10,000 nm Hint – see Figure 11 on the Laser Surgery Basics page
10. Soft tissue absorption coefficient around 1,000 nm is:< 1 cm⁻¹ > 1 cm⁻¹ > 10 cm⁻¹ > 500 cm⁻¹ > 3,000 cm⁻¹ Hint – see Figure 1 on the Laser Surgery Basics page
11. The depth of incision with a focused laser beam is?Proportional to laser average power Inversely proportional to focal spot size Inversely proportional to hand-speed All of the above Hint – see Incision and Coagulation/Hemostasis Depth Control During a CO2 Laser Lingual Frenectomy
12. Which of the below statements is TRUE?CO₂ laser wavelength is 1,000+ more efficient for soft tissue photo-thermal cutting than dental diode’ wavelength Due to strong absorption by the soft tissue, mid-infrared Erbium and infrared CO₂ laser wavelengths are efficient and spatially accurate ablation tools All of the above Hint – see Laser Surgery Basics page
13. Which of the below statements is FALSE?CO₂ laser wavelength is 10+ times more efficient for soft tissue coagulation and hemostasis than Erbium laser wavelength The Nd:YAG laser’s 1,064-nm wavelength is an efficient scalpel but a poor coagulator All of the above Hint – see Laser Surgery Basics page
14. Which of the below statements is FALSE?Coagulation depth of a CO₂ laser can be increased by an increase in pulse width/rate, and by a reduction of pulse power/fluence Healing after the scalpel excision takes 2-3 weeks for wounds that with CO₂ laser takes 7-10 days. A sub-50-µm thin coagulation zone was reported for the 10,600 nm CO₂ laser Hint – see Hemostasis and Coagulation with Ablative Soft-Tissue Dental Lasers and Hot-Tip Devices
15. Which of the below statements is TRUE?Near-IR diodes are non-laser thermal tools for soft tissue cutting In Near-IR diodes for cutting, laser optical energy is used to heat up the charred distal end of the glass tip Near-IR diodes are efficient coagulators All of the above Hint – see Laser Surgery Basics page
16. The advantage of the CO2 laser for soft tissue surgery is:Ability to cut radiantly (non-contact) with simultaneous hemostasis and coagulation Post-operative swelling Weak light absorption in soft tissue Strong light scattering in soft tissue Hint – see Laser Surgery Basics page
17. The coagulation and hemostasis effects with CO2 lasers can be increased by:De-focusing laser beam Turning laser off Increasing the power Reducing the laser spot size Hint – see Laser Surgery Basics page
18. Which of the below statements is TRUE?CO₂ laser wavelength is 1,000+ times more efficient for soft tissue cutting than dental diode’ wavelength All lasers are efficient at both coagulating and cutting Erbium wavelength is 10+ times more efficient for soft tissue coagulation and hemostasis than CO₂ laser wavelength None of the above Hint – see Laser Surgery Basics page
19. Which of the below statements is TRUE?Laser light absorption by soft tissue is wavelength independent Laser light absorption and scattering by soft tissue are crucial to understanding laser cutting and coagulating abilities For Erbium and CO₂ laser wavelengths, light scattering by the soft tissue is significant Hint – see Laser Surgery Basics page
20. Excision with a CO2 laser is characterized by less scarring than with the scalpel due to:Smaller number myofibroblasts in the laser-irradiated wound Larger number myofibroblasts in the laser-irradiated wound Strong absorption and weak scattering at CO₂ laser wavelength Hint – see Incision and Coagulation/Hemostasis Depth Control During a CO2 Laser Lingual Frenectomy
21. Which of the below is FALSE?Diode wavelengths belong to the near-infrared spectrum Diodes are non-laser thermal tools for soft tissue cutting Diode devices are poor coagulators Diode devices for cutting use laser optical energy to heat up the charred distal end of the fiberglass tip Hint – see Laser Surgery Basics page
22. The surgical site after SuperPulse CO2 laser treatmentIs often be left to heal by second intention Shows minimal swelling Shows minimal thermal damage All of the above Hint – see Laser Surgery Basics page
23. De-focusing the laser beamCreates a deeper cut Increases coagulation and hemostatic effects Does not affect laser-tissue interaction Enhances ablation Hint – see Laser Surgery Basics page
24. Identify TRUE statements below. Laser beam intensity, as it propagates from the surface into the tissue, is characterized as follows:Intensity increases Intensity decreases Intensity oscillates Hint – see Laser Surgery Basics page
25. Describe the most significant features of a SuperPulsed CO2 laserIt cools the tissue It minimizes collateral damage to surrounding tissue It maximizes coagulation It provides ablation without vaporizing histological water Hint – see Laser Surgery Basics page
26. Which laser, Erbium or CO2 , causes LESSER thermal damage and intra-operative pain?CO₂ laser Erbium laser Hint – see Laser Surgery Basics page
27. For diode laser, what are the ways to maximize the depth of thermal damage?Non-contact, un-initiated stationary tip, long exposure time Contact, initiated stationary tip, extended contact time of the tip with the tissue All of the above Hint – see Laser Surgery Basics page
28. For diode laser hot tip cautery incisions, at what hand-speed is the depth of thermal damage the greatest?Slow Hand-speed Fast Hand-speed Hint – see Laser Surgery Basics page
29. For diode laser hot tip cautery incisions, at what hand-speed is the depth of thermal damage the least?Fast Hand-speed Slow Hand-speed Hint – see Laser Surgery Basics page
30. For diode laser hot tip cautery incision to be effective, the tip temperature needs to be?Hot at hundreds of degrees Celsius Less than 100° Celsius Room temperature Hint – see Laser Surgery Basics page
31. For diode laser hot tip cautery, what is the incision depth?Absorption depth of the diode’s wavelength in the tissue The depth of tip’s insertion into the tissue Scattering depth of the diode’s wavelength in the tissue Hint – see Laser Surgery Basics page
