A general overview of the uses of lasers in the field of dentistry

1. Dept. of Oral and Maxillofacial Surgery
By,
DINESHWARRAN RAJENDRAN (CRI)
Guided by,
DR. R.KANNAN, MDS
Professor of Oral and Maxillofacial Surgery

2. Topics
• Introduction
• History
• Mechanism of Action
• Application of Lasers in Dentistry
• Advantages and Disadvantages of Lasers
• Safety Measures
• Examples of Dental Laser Therapies
• Video Presentations
• Conclusion

3. Introductio
n
Definition:
LASER
 A device that emits light through a process of optical
amplification based on the stimulated emission of
electromagnetic radiation

4. Features: Spatially coherent, which means that either
the light is emitted in a narrow, low divergence beam.
Many uses of lasers in daily life includes :
- In consumer devices such as DVD players, laser printers,
and barcode scanners
- In medicine for laser surgery and various skin treatments
- In industry for cutting and welding materials
- In military and law enforcement devices for marking targets
and measuring range and speed

5. In Dentistry,
Laser dentistry A precise and effective way to perform
many dental procedures. The potential for
laser dentistry to improve dental
procedures rests by allowing for treatment
of a highly specific area of focus without
damaging surrounding tissues.

6. History
1917
Albert Einstein established the
theoretical foundations for the laser
Quantum Theory of Radiation.
1959
Gordon Gould published the term
LASER in the paper The LASER.
May 16, 1960,
Theodore H. Maiman operated the
first functioning laser, the Ruby laser
at 694 nanometers wavelength

7. Dental Lasers
 1993: Nd:YAG Laser.
 1994: CO2 Laser.
 1996: Laser welder.
 1998 : Er:YAG Laser.

8. Mechanism of Action
• Laser Physics
• Design of Laser Medium
• Tissue- Laser Interaction

9. Laser Physics

10. Design of Laser Medium
Components of a typical laser:
1. Gain medium
2. Laser pumping energy
3. High reflector
4. Output coupler
5. Laser beam

11. Tissue-Laser Interaction
Absorption
Transmission
Reflection
Scattering
Laser light can have four different interactions with the target tissue,
depending on the optical properties of that tissue :

12. Different Laser-Tissue Interactions

13. • Using the principle of selective photothermolysis, these laser target
different chromophores in the skin, which selectively absorb the laser or
light energy as heat and yield the desired response.
Chromophores
absorb the
light
Physical,
mechanical,
chemical,
temperature
changes may
occur
This energy
travels at
different
wavelength
and is
absorbed by a
‘target’

14. Different Temperature Effects

15. Applications of Lasers in
Dentistry
• The rapid development of laser technology has seen its
introduction into various fields of dentistry.

16. 1. Diagnosis
• · Detection of pulp vitality
• · Doppler flowmetry
• · Laser fluorescence- Detection of caries, bacteria and dysplastic changes in the
diagnosis of cancer
2. Hard tissue applications
• · Caries removal and cavity preparation
• · Re-contouring of bone (crown lengthening)
• · Endodontic (root canal preparation ,sterilization and Apicectomy)
• · Laser etching
• · Caries resistance
3. Soft tissue applications
• · Laser-assisted soft tissue curettage and peri-apical surgery
• · Bacterial decontamination
• · Gingivectomy and Gingivoplasty
• · Gingival retraction for impressions
• · Implant exposure

17. Soft tissue applications (cont.)
• · Biopsy incision and excision
• · Treatment of aphthous ulcers and Oral lesion therapy
• · Coagulation / Hemostasis
• · Tissue fusion - replacing sutures
• · Laser-assisted flap surgery
• · Removal of granulation tissue
• · Pulp capping, Pulpotomy and pulpectomy
• · Operculectomy and Vestibuloplasty
• · Incisions and draining of abscesses
• · Removal of hyperplastic tissues and Fibroma
4. Laser-induced analgesia
5. Laser activation
• · Restorations (composite resin)
• · Bleaching agents
6. Other
• · Removal of root canal filling material and fractured instrument
• · Softening gutta-percha
• · Removal of moisture/drying of canal

18. Lasers in Dentistry
Soft tissue lasers
CO2
Laser
ND YAG
Laser
Hard tissue lasers
ER YAG Excimer
Types of Lasers Used in Dentistry

19. Carbon Dioxide Laser
 Mode : vaporisation, cutting (>100˚C)
 Specification : 10.6 micron wavelength
Used effectively in treating patients with oral lesions with
blood dyscrasias.
 Oral indication:
a. Excision of pre-malignant lesions
b. Excision/biopsy
c. Hemiglossectomy
d. Adhesive microvascular/macro neural
 Disadvantages :
-Cornea at risk
-Haemostasis may not be adequate on
very vascular area (posterior tongue)

20. ND-YAG Laser (Neodymium doped-
Yttrium Aluminium Garnet)
 Mode: coagulation (>60˚c), central vaporisation
 Specification : 1.06 micron wavelength
Can be combined with CO2 (combo laser) or KTP
 Oral indications:
a. Coagulation of very vascular lesions or near major
blood vessel
b. Excision in vascular areas such as posterior tongue
d. Gingivectomy
e. Frenectomy
 Disadvantages:
- Retina at risk
- Penetration could cause inadvertent spread
- Oedema more than CO2 laser

21. KTP Laser (Potassium Titanyl
Phosphate)
 Modality : cutting with moderate coagulation
 Specification : 0.53 micron wavelength
Can be combined with Nd-YAG laser
 Oral indications
a. Excision in vascular areas, eg. Tonsillectomy
 Disadvantage
- Retina at risk

22. Comparison of The Lasers

23. Advantages and Disadvantages
of Lasers
Advantages:
 Less pain in some instances (reducing the need
for anesthesia)
 Reduce anxiety in patients uncomfortable with
the use of the dental drill.
 Minimize bleeding (high-energy beam
photocoagulation) and swelling.
 Reduce bacterial infections (sterilizes the area
being worked on)
 Preserve more healthy tooth during cavity
treatment.

24. Disadvantages:
 Lasers can’t be used on teeth with fillings that
are already in place.
 Lasers can't be used in many commonly
performed dental procedures. Eg. lasers can't be
used to fill cavities located between teeth,
cavities around old fillings, and large cavities.
 Traditional drills may still be needed to shape the
filling, adjust the bite, and polish the filling even
when a laser is used.
 Do not eliminate the need for anesthesia.
 More expensive since the cost of the laser is
much higher.

25. Safety Measures
Dental lasers generally fall into Class 4

26. Precautions:
 Safety goggle (should be worn by patient and
operator)
 Lock the door during the treatment
 Never look directly into the laser beam
 Never point the laser hand-piece at any person
except at the treated area
 Never use the laser in the presence of flammable
anaesthetics
 Never step on or abruptly bend the fibre optic
cable
 Never move the laser machine during operation

27. Examples of Dental Laser
Therapies
Leukoplakia

28. Gingivectomy

29. Operculectomy

30. Pyogenic Granuloma Excision

31. Frenectomy

32. Video Presentation

33. Conclusion
Traditional
Surgery
Laser SurgerySubject
YesNo or mildAnesthesia
Yes depends on
operating zone
No or minimalBleeding
Sedation dependedSlight irritationPain
Time consumingLess timeTime
Yes in invasive
procedures
No needSuturing
Less expensiveExpensiveCost
MoreMinimalPostoperative
complications

34. Traditional
Surgery
Laser SurgerySubject
SlowerRapidHealing
Traumatic excisionDehydration and
carbonization
Method of pathology
elimination
Slight worse
<depended>
BetterDentist comfort
More convenientComplicatedProcedure
LessMoreTeam work
SameSameExperience

36. Thank You.