Lasers and its application in periodontics

2. Lasers and its
appLications in
periodontoLogy
presented By:
shiLpa shivanand
ii Mds

3. Contents
Introduction.
Historical perspective.
LASER properties.
LASER physics.
LASER parts and delivery systems.
LASER classification.
Biologic rationale: LASER –tissue interactions.
LASERS-
 Argon, Diode, Nd:YAG, Er:YAG, Co 2 laser.

4. Contents
Laser Safety.
Applications in dentistry.
Clinical Applications in Periodontics.
Literature review.
Conclusion
References

5. introduction
L- Light
A- Amplification
S- Stimulated
E- Emission
R- Radiation

6. historicaL perspective
1917- Principle of stimulated emission by Albert Einstein.
“Zur Quantern Theorie der Strahlung”
1954: Townes and Gordon- MASER.
1957- Gordon Gould introduced the term LASER.
1960- Theodore Maiman- First LASER- ruby – active
medium.
1961- Javan.- He-Ne laser.

7. historicaL perspective
1964- Nd YAG- Geusic.
1965- Co2 Laser- Patel.
1989- Myers and Myers-FDA approval for use of laser in
dentistry- Nd YAG laser.
1990- Opthalmic application- ruby laser.
1995- dental use started.

8. properties of Laser

9. MonochroMatic Light
Mono chromatic light has a very narrow range of
frequency and single wavelength (i.e. it is only made of
light of one colour)

10. coherence
• All the emitted photons are in phase with each other
and have identical peaks and valleys.

11. directionaLity

12. Laser physics
How is it produced??

13. Laser%2C_quantum_principle.ogv.720p.webm

14. parts of a Laser
Active medium/Gain:
Gas , solid, liquid suspended in an optical cavity.
Power supply: external energy source- flash lamp/ electrical
energy.
Optical resonator: mirrors for amplification.
Cooling system, Control system, Delivery system.

16. active MediuM
Phase Example
Gas Argon, Co2
Solid Diode
Solid Nd:YAG
Solid Er:YAG
Liquid Red dye
Usually defines laser type.

17. Laser deLivery systeMs

18. ARTICULATED
ARMS

19. Consist of a series of rigid hollow tubes with mirrors at each
joint (called a knuckle)
Mirrors reflect the energy down the length of the tube.
The laser energy exits the tube through a handpiece

20. disadvantages
1 . Awkward 3-D maneuverability of the arm.
2 . Mirrors at each knuckle must be aligned precisely.
 A misalignment of the mirrors could cause a drop-off in the
amount of energy transmitted to the handpiece.

21. HOLLOW
WAVEGUIDE

22. Semi rigid hollow tube with reflective interior mirror
finish.
Laser energy is reflected along this tube and exits through
a handpiece at the surgical end with the beam striking the
tissue in a noncontact fashion.

23. This handpiece can be attached to an accessory tip
of sapphire or hollow metal for contact with the
surgical site.
lenses within the laser instrument focus the beam

24. optic fiBer
Smaller in diameter with sizes ranging from 200
-1000 μm in diameter
 Fits into a handpiece
Used in contact or noncontact mode
Focal point is at or near the tip, which has the greatest
energy.

26. Laser deLivery systeMs
Delivery system type
Articulated arm Hollow tubes, 45 degree mirrors
Hollow waveguide Semi-rigid tube with internal reflective pathway
Optic fiber/ rigid tip Quartz-silica flexible fiber with quartz, sapphire
tip
Hand held unit Low power lasers.
Erbium family- fibers with low content of
OH ion are used. (eg) Zirconium fluoride

27. Modes of operation of Laser
Continuous wave
 Gated pulsed mode (Physical gating of beam)
 Free running pulsed mode (Property of the active medium)

30. Focused De-focused
Laser beam hits tissue
at its focal point-
narrowest diameter.
Cutting mode
Beam moved away
from its focal point.
Wider area of tissue
affected as beam
diameter increases.
Ablative mode.
LLLT.
Laser operation paraMeters

31. Contact Non- contact
Tip is in contact with
tissue.
Concentrated delivery
of laser energy.
Char tissue formation
at tip.
Tactile feedback is
available
Tip is kept 0.5 to 1 mm
away from tissue.
Laser energy delivered
at the surface is
reduced.
Laser OperatiOn parameters

32. BiOLOgic ratiOnaLe fOr Laser use
Laser-tissue interactiOns
LASER-TISSUE INTERACTION:
1. Reflection.
2. Transmission.
3. Scattering.
4. Absorption.

33. aBsOrptiOn
Depends on the tissue characteristics, such as pigmentation
and water content, and on the laser wavelength and
emission mode.
Hemoglobin is strongly absorbed by blue and green
wavelengths. (500–1000 nm)
The pigment melanin, which imparts color to skin, is
strongly absorbed by short wavelengths. (Diode and
Nd:YAG)

34. transmissiOn
Water, for example, is relatively transparent to the shorter
wavelengths like argon, diode, and Nd:YAG, whereas tissue
fluids readily absorb the erbium family and CO2 at the
outer surface, so there is little energy transmitted to
adjacent tissues.

35. refLectiOn
A caries-detecting laser device uses the reflected light to measure
the degree of sound tooth structure.
This reflection can be dangerous because the energy is directed to
an unintentional target, such as the eyes; this is a major safety
concern for laser operation.

36. scattering
Weakening the intended energy and possibly producing
no useful biologic effect.
Cause heat transfer to the tissue adjacent to the surgical
site, and unwanted damage could occur.
However a beam deflected in different directions is useful
in facilitating the curing of composite resin or in covering
a broad area.

37. tHeOreticaL ZOnes Of tissue cHange assOciateD
WitH sOft tissue eXpOsure tO Laser LigHt

38. Benefits Of Laser – tissue interactiOn
Soft tissue:
 Cut, coagulate, ablate or vaporize target tissue elements
 Sealing of small blood vessels
 Sealing of small lymphatic vessels
 Sterilizing of tissue- Eschar
 Decreased post-operative tissue shrinkage

39. tHeOreticaL ZOne Of tissue cHange assOciateD WitH
HarD DentaL tissue eXpOsure tO Laser LigHt

40. Laser effects are Due tO:
Photothermal.
Photochemical.
Photoacoustic.
Biostimulation.
Photodynamic.
Photovaporolysis.
Photoplasmolysis.

41. pHOtOtHermaL effects
Tissue temperature (degree
celsius)
Observed effect
37-50 Hyperthermia
> 60 Coagulation, protein denaturation
70-90 Welding
100-150 Vaporization
>200 Carbonization

42. pHOtOacOustic
The photoacoustic effect is a conversion between light and
acoustic waves due to absorption and localized thermal
excitation.
When rapid pulses of light are incident on a sample of
matter, they can be absorbed and the resulting energy will
then be radiated as heat.
This heat causes detectable sound waves due to pressure
variation in the surrounding medium.

43. Photovaporolysis Photoplasmolysis
Ascendant heat levels-
phase transfer from
liquid to vapor.
Tissue removed by
formation of
electrically charged
ions and particles in a
semi-gaseous high
energy state.
Laser effects

44. Photochemical Biostimulation
Absorption by
chromophores-
Tissue response in
terms of change of
covalent structure.
Believed to work towards
healing by stimulation of
factors and processes
involved in healing.
Below surgical threshold.
Useful for pain relief,
increased collagen
growth and anti-
inflammatory activity
Laser effects

46. WHat DOes tHe OperatOr cOntrOL?

47. cLassificatiOns
Lasers are named according to:
Active medium
Wavelength
Delivery systems
Emission modes
Tissue absorption
Clinical Application

48. cLassificatiOn

49. cLassificatiOn Of Laser
(periODOntOLOgy 2000, 2009)

50. Classification of LASER- based on safety
Based on the potential of the primary laser beam or the
reflected beam to cause biologic damage to the eye or skin.
Four basic classes:
 Class I.
 Class II: a,b
 Class III: a, b
 Class IV.

51. cLassificatiOn Of Lasers
Class I lasers
Do not pose a health
hazard.
Beam is completely
enclosed and does not exit
the housing.
Max power output: 1/10
th of milliwatt
Eg: CD player.
Class II Lasers:
Visible light with low
power output.
No hazard- blinking and
aversion reaction.
Max power output is 1
mW.
Eg: bar code scanner,
laser pointer
Two subdivisions:
IIa: dangerous- >1000
sec.
IIb: ¼ th of second.

52. Laser cLassificatiOn
Class IIIa:
Any wavelength.
Max Output power: 0.1 to
0.5 W.
Danger > ¼ th of a
second.
Caution label.
Class IIIb:
Hazard to eye- direct or
reflected beam,
irrespective of time of
exposure.
Safe with matted surface
and no fire hazard.
Max output power: 0.5 to
5W.

53. cLassificatiOn Of Lasers
Class IV lasers:
Hazardous for direct viewing and reflection.
Max output power > 5 W.
Fire and skin hazards.
Use safety glasses
Dental lasers are Class IIIb or Class IV lasers.

54. aBsOrptiOn cHaracteristics Of
DentaL Lasers
LASER Wavelength Type Chromophore
Argon 488-515 nm Gas Hemoglobin,
melanin
He Ne 632 nm Gas Melanin
Diode 810-980 nm Solid Melanin,
hemoglobin.
Nd: YAG 1064 nm Solid Melanin, water
Ho: YAG 2120 nm Solid Water, HA.
Erbium family 2790-2940 nm Solid Water, HA.
Co2 9300, 9600,
10600 nm
Gas Water, HA.

55. argOn Laser
LASER characteristics
Wavelength 488 to 514 nm
Active medium Argon Gas
Delivery system Optical fiber
Mode of operation Continuous wave
Chromophore Melanin pigment, hemoglobin,
hemosiderin
Applications Soft tissue only.
Pocket debridement and de-
epithelialization for GTR
“Laser Pocket thermolysis”:
Finkbeiner 1995- absorption by
black pigmented bacteria- bacterial
load reduction in the periodontal
pocket.
Blue wavelength  488nm 
composite curing
Green wavelength  510nm  soft
tissue procedures, coagulation

56. argOn
Acute inflammatory periodontal
disease and highly vascularized
lesions, such as a hemangioma,
are ideally suited for treatment.
The poor absorption into
enamel and dentin is advantageous
when using this laser for cutting
and sculpting gingival tissues
because there is minimal interaction
and thus no damage to the tooth
surface during those procedures.

57. DiODe Laser
LASER characteristics
Wavelength 810 to 980 nm
Active medium Semi-conductor diode
Delivery system Optical fiber- quartz or silica
Mode of operation Continuous wave, gated pulsed mode.
Used in focused and de-focused modes.
Chromophore Melanin, hemoglobin.
Applications Primarily soft tissue applications- all
minor surgical procedures.
The chief advantage of the diode lasers is one of a smaller
size, portable instrument.
HOT TIP EFFECT 
heat accumulation at
tip  thick
coagulating layer
Less tissue
penetration ,
Deeper
coagulation
DIODENT
Visible red diode
655nm
1mW

58. nD:yag Laser
LASER characteristics
Wavelength 1064 nm
Active medium Neodymium in YAG crystal
Delivery system Optical fiber
Mode of operation Continuous wave, pulsed wave
Chromophore Hemoglobin, melanin, water
Applications Effective for soft and Hard tissue->
Hemostasis, treatment of apthous
ulcers, or pulpal analgesia.
Causes more thermal damage
Earliest FDA approved laser for dental
use.
Nd:YAG 1340 nm, Black pigmented tissue
absorption.
Do not use for disinfection of implant surfaces- damage to sand
blasted and acid etched surfaces (Kreisler et al 2002).

59. erBium famiLy Of Lasers
Er YAG- 2940 nm: Zharikov et al 1975.
Er Cr YSGG- 2780 nm: Zharikov et al 1984 and Moulton et
al 1988.
1988: Phagdiwala: Er YAG laser: ability to ablate the
dentinal hard tissue.
1989: Pulsed Erbium laser: Keller and Hibst- enamel ,
dentin and bone.
1995: Commercially available.
1997: introduced for use in dentistry.

60. Wavelength 2940 and 2780
Active medium Erbium ion embedded in YAG or
YSGG crystal
Delivery system Articulated arm, Hollow wave guide,
Water free compound like Zirconium
fluoride fiber with air and water in the
co-axial cable.
Mode of operation Continuous wave, free running pulsed
mode. Used in focused and de-focused
modes.
Chromophore Water, Hydroxyapatite
The advantage of erbium lasers for restorative dentistry is that
a carious lesion in close proximity to the gingiva can be treated
and the soft tissue recontoured with the same instrumentation.

61. MOA of Er laser  photoablation
Layers formed  superficial significantly altered
 intermediate
 deeper/ less affected
Superficial layer  micro-cracking, disorganization, slight
recrystallization of apatite, reduction of surrounding
organic matrix
Intermediate layer  micro-explosion due to energy
accumulation
Deep  no change

62. Co2 laser
Wavelength 9300, 9600, 10600 nm
Active medium Carbon dioxide Gas
Delivery system Articulated arm
Mode of operation Continuous wave, gated pulsed mode.
Used in focused and de-focused
modes.
Chromophore Water, Hydroxyapatite
Limitation: High risk of carbonization (water absorption  generates
more heat  carbonizes tissue)
Advantage : carbonized / charred layer acts as biological dressing

63. Carbonization
Use limited to soft tissue procedures as
it produces severe thermal damage, like
cracking, melting and carbonization of
the adjacent root cementum and dentin
Spencer (1996),Israel et al(1997) ,
Barone et al (2002)
Highly absorbed by main mineral
component of hard tissue, especially
phosphate ions leading to
 Carbonization of organic components
 Melting of inorganic ones

64. Advantages Disadvantages
Hemostasis.
Ablation.
Detoxification.
Bactericidal activity.
Osseous tissue removal
and contouring easy
with Er family
Hard tissue damage
(bone)
High cost.
Risk of pulpal damage.
No single wavelength
can treat all diseases
lasers

65. laser safety
Regulatory
organizations:
 CDRH center for
devices and radiologic
health
 ANSIAmerican
National Standards
Institute
 OSHA occupational
safety and health
administration
Laser safety officer.
Environment: warning
signs, restricted access,
reflective surface
minimized.
Laser use
documentation.
Training.
Eye and tissue
protection.

66. eye damage
Part of eye damaged Laser type
Corneal damage Er Cr YSGG, Ho YAG, Er YAG, Co2
Lens damage Diode, Nd YAG, Ho YAG, Er Cr YSGG, Er
YAG
Aqueous damage Ho YAG, Er Cr YSGG, Er YAG
Retinal damage Argon, He Ne, Diode, Nd YAG

67. laser safety offiCer (lso)
Knowledge of operational
characteristics.
Supervises staff education
and training.
Laser maintenance and
calibration.
Posts warning signs.
Oversees personal
protection.
Incident reporting.
Knowledge about
regulations.
Regulates working area.

68. appliCations in dentistry
Biopsy.
Apicoectomy.
Teeth preparation.
Epulis fissuratum.
Residual ridge
modification.
Bleaching.
Impaction.
Pontic site preparation.
Tori reduction.
Soft tissue modification
around laminates.
Impacted teeth
exposure- orthodontic
movement.
Caries removal.
Root canal disinfection.

69. CliniCal appliCations in periodontiCs
Initial non-surgical
pocket therapy.
Frenectomy.
Gingivectomy.
Soft tissue grafting.
De-pigmentation.
Desensitization
Removal of granulation
tissue.
Osseous recontouring.
Crown lengthening.
Surgery- implants.
Peri-implantitis.
Operculectomy.

70. Conventional methods LASER
Bleeding- surgical field.
Suturing.
Local anesthesia.
Post-operative discomfort.
Healing time.
Post-operative
complications.
Infection.
Periodontal dressings.
Effective hemostasis.
No sutures. (concept of
tissue welding).
Topical anesthetic- some
procedures.
Faster healing.
Minimal/no post operative
complications.
Laser sterilization of
wound site.
Laser bandage.
Why lasers in periodontiCs…

71. lasers used in periodontiCs

74. gingival soft tissue proCedures
Advantages of lasers over conventional:
 Hemostasis.
 Ablation.
 Little wound contraction/ minimal scarring.
 Faster healing.
 Less post-operative discomfort.
 Less risk of damage to underlying structures as compared to
cautery.

75. gingival soft tissue proCedures
Indications:
 Gingivectomy.
 Gingivoplasty.
 Frenectomy/ frenotomy.
 Vestibuloplasty.
 Operculectomy.
 Depigmentation.
Lasers used;
 Diode.
 Nd YAG.
 Er YAG.
 Co2.
Diode and Nd YAG: deep
penetration .
Er YAG, Co2: superficial
action.

76. gingival soft tissue proCedures
Diode and Nd YAG:
Effective for cutting and
reshaping of soft tissue.
Good hemostasis
Greater thermal effects.
Thicker coagulated layer.
Co2 laser:
Rapid ablation of soft
tissue.
Good hemostasis.
Effective even for thick
tissue.
Risk of charring- thermal
damage.

77. gingival soft tissue proCedures.
Er YAG :
Fine cutting can be done.
Less hemostasis as
compared to other lasers.
Very less thermal damage:
use with irrigation.
Width of thermally
affected layer: 5-20
microns (Aoki et al 2005)
Er YAG:
Safer even in thin tissues.
Useful to remove
melanin and metal
tattoos.

78. non surgiCal therapy
Introduction:
Primarily aimed at efficient removal of plaque and
calculus and reduction of bacterial load,
inflammation.
Conventional therapy limitations:
 Incomplete removal of calculus.
 Incomplete elimination of inflamed pocket lining.
Lasers used: Diode, Nd YAG, Er YAG, Co2 lasers.

79. subgingival CalCulus deteCtion- unique appliCation
for laser
Conventional method- tactile feel.
Latest: Er YAG laser with fluorescent feedback
system for calculus detection.
Rationale:
Difference in the fluorescence emission properties of
calculus and dental hard tissue when subjected to
irradiation with 655 nm diode laser.

80. Author and year Study design Objective Findings
Folwaczny M et al
2002
In vitro- extracted
teeth
Assess efficacy of
fluorescence
induced by 655
nmdiode laser to
detect subgingival
calculus
655 nm diode
laser- effective for
calculus detection
Krause F et al
2003
In vitro- histologic
study ( in presence
of saline/ blood)
Efficacy for
calculus detection
The laser
fluorescence
values co-relate
strongly with
calculus presence.
Scharwz F et al
2003
In vivo and in
vitro.
Er YAG with Diode
655 nm combined
Compare the new
system with SRP
for calculus
removal efficacy
Selective removal
of sub-gingival
calculus.
Sculean A et al
2004
Er YAG+ diode vs
SRP
Improvement of
clinical parameters
Similar results
with both systems
Tung OH et al
2008
Detection through the gingiva- based on autofluorescence- Ti
Sapphire laser
studies- sub gingival CalCulus deteCtion system

81. sub- gingival CalCulus removal
Author and Year LASER Study design Observation
period
Findings
Cobb et al 1992 Nd YAG Exp (Laser, Laser+
RP, RP+Laser),
Control
(untreated).
Immediately after
treatment
Low effectiveness of
calculus removal.
Decrease in no of
bacteria.
Scharwz et al 2003 Diode Exp (Laser),
Control (SRP)
Immediately after
trmt.
Not effective for
calculus removal.
Thermal damage to
root surface.
Scharwz et al 2001 Er YAG Laser, no control Immediately after
trmt.
Smooth root
surface
morphology.
Effective calculus
removal. No
thermal damage
Scharwz et al 2003 Er YAG with
fluorescent calculus
detection system
Exp (Laser),
Control (SRP- hand
scaler)
Immediately after
trmt .
Selective
subgingival calculus
removal. No
thermal damage,
less cementum
removal.

82. Diode laser Nd YAG laser
 Dry or saline moistened root
surfaces- no detectable
alterations.
 Blood coated specimens-
charring
(Kreisler M et al 2002)
 Morlock BJ et al 1992: surface
pitting, craters, melting,
carbonization of root surface.
 Spencer et al 1992, 1996:
decrease in protein/mineral
ratio, production of protein by-
products.
 Trylovich DJ et al 1992: Nd YAG
treated root surface – not
favorable for fibroblast
attachment.
 Thomas D et al 1994: Laser
followed by SRP- restores the
biocompatibility of root surface
root surfaCe alterations

83. Co2 laser Erbium family
 SpencerP, Cobb CM et al 1996:
 Carbonized layer on root
surface.
 Cyanamide , cyanate ions-
detected on the carbonized
layer- FTIS method.
 Gopin BW et al 1997: Char
layer inhibits periodontal soft
tissue attachment.
 Co2 laser contraindicated for
root surface treatment in
focused mode.
• Aoki et al 2000: Er YAG with
coolant:
 micro-irregular surface.
 No thermal effects such as
cracking, fissuring.
• Sasaki KM et al 2002: no
major chemical or
compositional change- on
root cementum or dentin.
• Biocompatability of root
surface: micro-irregularity
offers better attachment to
fibroblasts (Scharwz F et al
2003).
root surfaCe alterations

84. baCterial reduCtion
The only two soft tissue wavelengths that currently meet
the criterion of having a delivery system able to deliver
laser energy efficiently and effectively to the periodontal
pockets for nonsurgical periodontal therapy are Nd:YAG
and diode.
Well absorbed by melanin and hemoglobin and other
chormophores present in periodontally diseased tissues.
The laser energy is transmitted through water and poorly
absorbed in hydroxyapitite.

85. Both of these wavelengths have been shown to be extremely
effective against periodontal pathogens in vivo and in vitro
( Moritz 1998, Pinhero J 1997)
These investigators concluded that the diode laser revealed
a bactericidal effect, helped reduce inflammation, and
supported healing of the periodontal pockets through the
elimination of bacteria.

86. detoxifiCation effeCts: basiC studies
Author and Year Laser Findings
Misra V et al 1999 Co2 Smear layer removal.
Crespi et al 2002 Co2 Root surface de-
contamination. Favorable
for cell attachment.
White JM et al 1991 Nd YAG De-contamination of
irradiated dentin
Fukuda M et al 1994 Nd YAG Inactivation of endotoxin
of periodontally diseased
root surface.
Ando Y et al 1996 Er YAG High bactericidal activity
at low energy settings
Yamaguchi et al 1997 Er YAG Removes LPS diffused
into root surface

87. Low Level LasersLow Level Lasers

88. 1903: N.R. FinesenN.R. Finesen, the father of modern phototherapy, first, the father of modern phototherapy, first
described low level ultraviolet in the treatment of lupusdescribed low level ultraviolet in the treatment of lupus
vulgaris.vulgaris.
 The treatment was low level effect of non coherent light.The treatment was low level effect of non coherent light.
1960s: The use of LLLT first initiated in medicine for inThe use of LLLT first initiated in medicine for in
vitro experiments to determine the effects on cell cultures andvitro experiments to determine the effects on cell cultures and
increased blood circulation within regenerating tissue.increased blood circulation within regenerating tissue.
historiCal aspeCts

89. • Generally smaller, less expensive lasers that operate in
the milliwatts range, 1-500 mw are used.
• The therapy performed with such lasers are often called
“low level laser therapy” (LLLT) or also known as
“therapeutic lasers”
• Generally operate in the visible and the infrared
spectrum, 600 – 900 nm wavelengths.
• The energy used is indicated in joules.
• Suitable therapeutic energies range from 1 – 10 joules
per point.

90. All commercially available LLLT system are
generally variants of Gallium, Aluminum, Arsenide
(Ga, Al, As) which emit in the near infrared
spectrum (700 – 940 nm).

91. Low LeveL LasersLow LeveL Lasers
Helium – neon laserHelium – neon laser
Gallium – aluminum – arsenide diode laserGallium – aluminum – arsenide diode laser
Gallium – arsenide diode laserGallium – arsenide diode laser
Argon ion laserArgon ion laser
Defocused CoDefocused Co22 laserlaser
Defocused Nd:YAG laserDefocused Nd:YAG laser

92. BiostimuLation effects of Low LeveL Laser
 Reduction of discomfort / pain (Kreisler MB et al 2004).
 Promotion of wound healing (Qadri T et al 2005).
 Bone regeneration (Merli LA et al 2005).
 Suppression of inflammatory process. (Qadri T et al 2005).
 Activation of gingival and periodontal ligament fibroblast
(Kreisler M et al 2003), growth factor release (Saygun I et al
2007).
 Alteration of gene expression of inflammatory cytokines
(Safavi SM et al 2007).
 Photobiostimulaation (Garcia et al 2012)

93. Laser assisted new attachment Procedure
LANAP
Gold and Villardi 1994, safe application of the Nd YAG laser
for removal of pocket epithelium lining without carbonization of
the underlying connective tissue.
Approved by FDA for use.
Yukna et al 2007- case series- histologic study- new
cementum with new connective tissue attachment on
previously diseased root surface.

94. 1st
pass –
laser
troughing
2nd
pass –
long pulse

95. Author and
Year
Laser used Study design Observation
period
Findings
Ben Hatit et al
1996
Nd YAG RCT
SRP+ Laser, SRP
Immediately after,
2, 6 weeks and 10
weeks
Significantly
reduced post-
therapy levels of
bacteria following
adjunctive laser.
Liu et al 1999 Nd YAG RCT- split mouth.
Laser, Laser+ SRP
(6 weeks later)
and SRP + Laser
(6 weeks later).
12 weeks Less effectiveness
of laser treatment
in reducing IL-1
beta as compared
to SRP.
Miyazaki et al
2003
Nd YAG RCT (Laser vs
Ultrasonic)
1,4,12 weeks Similar results
between laser and
US- reductn of
P.ging and Il-1
beta levels.
Noguchi et al
2005
Nd YAG Laser, Laser+
local minocycline,
Laser+ povidone
iodine
1, 3 months Greater reduction
of bacteria on
laser+
minocycline
treated sites

96. Author and
Year
Laser used Study design Observation
periods
Findings
Moritz et al
1997
Diode SRP+ Laser,
SRP
1,2 weeks High bacterial
reduction in
SRP+ laser as
compared to
SRP sites alone.
Moritz et al
1998
Diode SRP + Laser,
SRP + H2 O2
rinse
6 months Higher reductn
in bacterial,
BOP, PD in SRP
+ laser sites.
Kresiler et al
2005
Diode RCT, split
mouth design.
SRP + Laser,
SRP alone.
3 months Greater
reduction of PD
and attachment
gain in Laser
adjunct sites
Miyazaki et al
2003
Co2 RCT, Laser vs
ultrasonic
1,4,12 weeks No decrease of
P.ging and IL-1
in laser sites.
But significant
decrease in US
sites.

97. Author and
Year
Laser used Study design Observation
period
Findings
Watanabe et al
1996
Er YAG Case series
(Laser only)
4 weeks Safe and
effective
calculus
removal .
Schwarz et al
2001
Er YAG Split mouth
design, RCT
(Laser vs SRP)
6 months Clinical
outcome similar
to SRP.
Sculean et al
2004
Er YAG RCT, split
mouth (Laser vs
Ultrasonic)
6 months Clinical
outcome similar
to Ultrasonic
scaling.
Tomasi et al
2006
Er YAG RCT, split
mouth (Laser vs
Ultrasonic)
6 months 1 month-
following
therapy, laser
treated sites-
better clinical
outcomes, no
difference in
microbiological
levels

98. surgicaL Pocket theraPy- Lasers
Lasers used: Co2 and Erbium family
Involves use of lasers for
 calculus removal,
 osseous surgery,
 de-toxification of the root surface and bone,
 granulation tissue removal
Advantage of Laser:
Better access in furcation areas, hemostasis, less post-
operative discomfort, faster healing.

99. Author and
Year
Laser used Animal model Study Objective Findings
Nelson et al 1989 Er YAG Rabbit Irradiated tissue
characteristics
Found useful as a
bone cutting tool
Lewandrowski et
al 1996
Er YAG Rat Cutting efficiency
and tissue
characteristics
Comparable
thermal damage
as mechanical cut
bone. Normal
fracture healing.
Friesen et al 1999 Co2, Nd YAG Rat Tissue
characteristics
Residual
carbonized tissue
and thermal
necrosis.
Sasaki et al 2002 Co2 and Er YAG Rat Tissue
characteristics
Er YAG- Tissue
removal, no
charring. Two
distinct layers.
Co2- charring and
no tissue removal.
Stubinger et al
2007
Er YAG Clinical- human Depth control of
laser
Laser could not
offer precise
depth control in
preparing
osetotomies.

100. Author Laser used Study design Observation
period
Findings
Centty et al 1997 Co2 RCT, split mouth.
OFD+ Laser, OFD
alone
Biopsy during
surgery
Laser eliminated
significantly more
sulcular epithelium
than conventional
surgery.
Schwarz et al 2003 Er YAG
( for root
conditioning)
RCT, split mouth.
OFD+ Laser+ EMD
vs OFD+
EMD+EDTA
6 months No significant
difference by using
laser for root
conditioning
Sculean et al 2004 Er YAG
(granulation tissue
removal)
RCT, split mouth.
OFD+ Laser vs
OFD alone.
6 months No significant
difference between
two groups in
clinical outcomes.
Gaspirc et al 2007 Er YAG
( bone defect
irradiation )
RCT, split mouth.
MWF+ laser vs
MWF alone
5 years Laser application-
greater gain in
attachment and
pocket depth
reduction.
surgicaL Pocket theraPy- cLinicaL studies

101. imPLant theraPy- management of Peri-
imPLantitis
Peri-implantitis – Management options-
Conventional- plastic curettes and antibiotics.
New option- Laser
Rationale:
 Disinfection and de-contamination of implant surface.
 Granulation tissue removal.
Lasers used: Diode, Co2, Erbium family.
Lasers contra-indicated: Nd YAG (Implant damage).

102. Author Laser used Study design Objective Findings
Schwarz et al
2006
Er YAG Clinical and
histological
Pocket
debridement
and de-
contamination
Clinical
improvements
at end of 6
months of
therapy is
similar to
conventional
therapy.
Deppe et al
2001
Co2 In vivo Decontaminatio
n
Safe for de-
contamination
of bone defects
around
implants.
Schwarz et al
2006
Er YAG In vivo Granulation
tissue removal
Laser better
than plastic
instruments
and antibiotics/
Ultrasonic
scalers.

103. Photodynamic theraPy in Laser
Main objective of periodontal therapy: eliminate the
deposits of bacteria.
Conventional mechanical therapy: incomplete elimination
due to
Anatomical complexity of root.
Deep periodontal pockets.

104. PrinciPLes Behind Pdt
TARGET
CELL
1
O2
1
O2
1O2
1
O2
1
O2
1
O2
1
O2
1
O2
light
PS
Cell death

105. destruction of PeriodontoPathogenic Bacteria
Polysaccharides in biofilm are highly sensitive to singlet
oxygen.
During inflammation reduced O2 consumption
change in pH
growth of anaerobes

106. PDT tissue blood flow and venous congestion
oxygenation of gingival tissues
21– 47 %
The activity of PDT ..been reported in vitro and in vivo .
 Greater bacterial reduction of S.sanguis numbers
compared with A. actinomycetamcomitans.
F.D.L. Mattiello et al.(2011)

108. anti- microBiaL Photosensitizing agents and the
waveLengths used.

109. heaLing after Laser theraPy
o Reports - laser created wounds heal more quickly and
produce less scar tissue than conventional scalpel
surgery.
o Contrary evidence from studies in pigs, rats and dogs
indicate that the healing of laser wounds is delayed, that
more initial tissue damage may result, and that wounds
have less tensile strength during the early phase of
healing. (Pick et al 1990)

110. Abergel et al (1984) experiment with cultured human skin
fibroblasts showed that collagen production and DNA
synthesis were delayed when the fibroblasts were exposed
to Nd: YAG laser radiation.
Iliria et al (2003) analyzed the biocompatibility of root
surfaces treated by Er: YAG laser and concluded that laser
irradiation promoted faster fibroblast adhesion and growth
than surfaces treated with root planing.
Garcia et al (2012) LLLT  enhanced healing 
biostimulation

111. recent advances
WATERLASE
Device that uses laser energized water to cut and coaglate soft
and hard tissue.
Er, Cr: YSGG laser 2,780nm - available as WATERLASE

113. uses
Full thickness flap
Partial thickness flap
Split thickness
Laser soft tissue curettage
Laser removal of diseasd, infected, inflamed, necrosed tissue
within the periodontal pocket
Removal of inflamed tissue, osteoplasty, osseous
recontouring……

114. Periowave
Photodynamic disinfection system utilizes nontoxic dye in
combination with a low-intensity lasers enabling singlet
oxygen molecules to destroy bacteria.

115. concLusion
Lasers in dentistry offer incredible precision, less pain,
faster healing and many more advantages.
It is most important for the dental practitioner to become
familiar with those principles and choose the proper laser
for the intended clinical application.

116. References
Dental clinics of North America. “ Lasers in
Clinical dentistry”. Oct 2004. Vol 48. Issue 4.
Application of antimicrobial photodynamic
therapy in periodontal and peri-implant diseases.
Periodontology 2000, Vol. 51, 2009, 109–140.
Application of lasers in periodontics: true
innovation or myth? Periodontology 2000, Vol. 50,
2009, 90–126.
The impact of laser application on periodontal and
peri-implant wound healing. Periodontology 2000,
Vol. 51, 2009, 79–108

117. Laser applications in dentistry – Robert N Conviesar
The biologic rationale for the use of lasers in
dentistry. Robert Convissar. DCNA 48(2004) 771-
794.
Lasers in periodontics . J Periodontol 2002,73:1231-
1239