1. Lasers are used in oral and maxillofacial surgery for excising both benign and malignant lesions with advantages over conventional surgery like more tissue preservation, less blood loss, and optional for further treatment. 2. The CO2 laser is commonly used as its wavelength is absorbed by water, providing hemostasis while limiting thermal damage. It allows precise excision of soft tissue lesions. 3. Proper laser safety equipment and protocols must be followed to prevent injury to patients and operators from beam reflection and potential fires from surgical drapes and airway tubes near the operative site.

1. Lasers in Oral and
Maxillofacial Surgery
Colin Hopper
UCLH Head and Neck Centre

2. Introduction
LASER is an acronym of light amplification
by stimulated emission of radiation.
Coherent , narrow low-divergence beam
Monochromatic

3. Theodore Maiman
• Maiman's laser, based on a synthetic ruby crystal grown by Dr.
Ralph L. Hutcheson, was first operated on 16th
May 1960 at the
Hughes Research Labs Malibu, California

4. CO² Laser
• The carbon dioxide laser was one of the
earliest gas lasers to be developed (invented
by Kumar Patel of Bell Labs in 1964)
• Highest-power continuous wave lasers
• Efficient: output power to pump power 20%.
• The CO2 laser produces a beam of infrared
with wavelength 9.4 to10.6 micrometers

5. Laser classifications
• According to active medium (gas,
liquid, solid or plasma)
• According to energy (high level laser
for surgical use as CO2 and Erbium:YAG
laser and low level laser for
therapeutic use as diode laser.

6. Background
• Transoral laser microsurgery maintains all
options for further treatment
• During the approach it can be converted to
external approach at any time
• Postoperatively laser surgery can be reapplied

7. Lasers - CO2
• Articulated arm
• Requires control technique
• Tipping point
• Needs mirror to get round corners

8. Laser-tissue interaction
Light can be:
– Reflected (bounces off)
– Scattered (random dispersal)
– Transmitted (passes through unchanged)
– Refracted (change in direction)
– Absorbed (maximal clinical benefit)

9. Reflection

10. Scattering

11. Transmission

12. Absorption

13. Laser injury
• The wound created
by the carbon dioxide
laser, showing the
representative zones
of injury.

14. Lasers
• With most surgical lasers, the physician
can control three variables:
– (1) power (measured in watts);
– (2) spot size (measured in millimeters); and
– (3) exposure time (measured in seconds).

15. Power
• Power is the least useful variable
– May be kept constant with widely varying
effects, depending on the
• spot size and
• duration of exposure
• Irradiance
– more useful measure of the intensity of the
beam at the focal spot
• it considers the surface area of the focal spot.

16. Spot Size
• Power and spot size are considered
together, and a combination is selected
to produce the appropriate irradiance.

17. Exposure Time
• The surgeon can vary the amount of
energy delivered to the target tissue by
varying the exposure time.
– Fluence refers to the amount of time
(measured in seconds) that a laser beam
irradiates a unit area of tissue at a constant
irradiance.

18. CO2 Laser
• Microspot CO2 Laser
– CO2 laser energy is absorbed by water
Provides excellent hemostasis
– Thermal trauma can be detrimental
– Thermal damage denatures collagen resulting
in scar formation and loss of mechanical
integrity (Blood vessels)

19. CO2 lasers and oral tissues
• The CO2 laser beam has a wavelength
of 10.6 Am, and the energy absorbed
by the oral soft tissues causes
vaporisation of the intra- and extra-
cellular fluid and destruction of the
cell membranes.
• It is an ideal means of removing soft
tissue lesions in the mouth.

20. Wound healing following CO2
laser surgery
• There is minimal damage to adjacent tissue and a
coagulum of denatured protein forms on the surface.
• No dressing is required, - lasered area left exposed
• Skin grafting of the laser wounds unnecessary.
• Acute inflammatory reaction delayed and minimal
myofibroblasts present, hence, little wound contraction.
• Small amounts of collagen laid down, resulting in little
scarring or restriction in movement of the soft tissues.
• However, epithelial regeneration is delayed,
and the wounds take a longer time to re-
epithelialise than following conventional
surgery.

21. Clinical application of CO2
laser
• It is used for excising benign,
premalignant and selected malignant
lesions of the soft tissues of the mouth

22. Benign oral lesions
• Blood vessels smaller than 0.5-mm diameter
are sealed spontaneously, allowing excellent
visibility and precision when dissecting
through the tissue planes.
• There is minimal cellular damage adjacent
to the plane of excision. This facilitates good
wound healing, and it also means that the
specimen can be removed without distortion,
enabling the pathologist to provide an
accurate histological diagnosis.

23. Premalignant mucosal lesions
• Frame discussed the controversies
concerning the aetiology, diagnosis,
assessment and management, and
demonstrated how the CO2 laser is the most
effective method of eliminating the lesion. It
allows precise excision, together with some
of the underlying connective tissue.
• The elimination of this deeper layer may
reduce the likelihood of recurrence, because
the subepthelial tissues may play a role in
the induction of mucosal disease.

24. Selected malignant lesions
• In selected patients with oral
squamous cell carcinoma, as part of
their overall oncological management,
the CO2 laser has a role to play in
excision of the lesion

25. Laser microsurgery has several advantages over
conventional, open surgery:
1-More normal tissue is saved
2-Normal tissues do not need to be divided to reach
the tumor, (as in standard, open surgery)
3-Patients spend less time in the hospital, (though the
time in the operating room may be longer)
4-Less blood loss
5-Conventional surgery and radiation remain options at
a later time if needed

26. Laser Safety
• Skin Protection
– When laser surgery is being performed,
• Beam might partially reflect off instruments.
• Saline-saturated surgical towels completely drape
the patient's face.
• Teeth in the operative field also need to be
protected.
• Surgical sponges, or specially constructed metal
dental impression trays can be used.

27. Eye protection

28. Laser Safety
• Aside from a few minor eye injuries from
a laser beam exposure, most serious
accidental injuries related to laser use
can be traced to the ignition of surgical
drapes and airway tubes

29. Complications
• One of the most devastating complications is
endotracheal tube ignition and resulting injury to the
laryngotracheal mucosa.
• A nonflammable, universally accepted endotracheal
tube for all types of laser surgery of the upper
aerodigestive tract does not exist.
• In the oral cavity this is not so great a problem and
tubes are easily isolated

47. Thank you