2. Laser is an acronym for light amplification by
stimulated emission of radiation.
The back formed verb to lase means “ to produce laser
light” or possibly “ to apply laser light to”.
The first laser was contributed by Mainmen in 1960.
the application of lasers in dentisty had been reported
from 1964.
4. co2 Lasers:
Used in gingivectomies, biopsies, and removal of
benign and malignant lesions & frenectomy.
Nd: YAG Lasers:
This lasers produces short pulsed, high energy beam that
cut, perforate, (or) fragment tissue.
Argon Laser:
This laser is based on gas of element argon, and emits bluish
green light.
6. When laser striker tissue it is absorbed, reflected,
scatterd or transmitted.
Absorption results in energy bron photons being
transferred to tissues carring bollowing effects.
1. Photo chemical
2. Photo decomposition
a) Photo ablation.
b) Photo distuption.
7. Treatment application are:
a) Laser welding
b) Stimulated intraoral laser microwelding
c) Laser etching
d) Laser bonding
e) Laser debonding of ceramic bracets
f) Laser-Structure based retent 10w brackets.
g) Porcelain surface treatment by laser for
Bracket-Porcelain bonding.
8. h) In reducing pain & discomfort during
orthodontic treatment.
i) Bone regeneration in mid palatal, suture during
expansion.
j Controlling growth of facial structure.
k) Rate of orthodontic tooth movement.
l) Prevention of dental caries during orthodontic
tooth Movement.
m) Inhibition of gingival embrasure space.
9. It is used for four main requirements.
1) To avoid study models.
2)To automatically discriminate geometric points
belonging to teeth and gum.
3)To calculate diagnostic parameter.
4)To make use of low cost & easy to use technology for
future commercial use.
A low poser Helium-Neon type laser is used.
10. Other laser scanning techniques are.
1) Confocal laser scanning microscopy produce blur-free
images of thick specimen at various depth.
2)Three dimensional dental cast analyzing system. Take
approximately 40minutes. Measurement error. Less
then 0.05 mm.
3)3D digital dental models. Emodels are designed. Can
move, rotate, 200mi on the model and can make
measurements in any plane orientation.
11. 3D laser scanner consists of
a) Slit laser projector.
b) A charged coupled device.
c) a data processing software.
Can also help in diagnosis & treatment plan in
orthodontic & orthognathic surgery.
12. It was invented by Hungarian physicist Dennis Gabor
in 1947.
Holography is advanced form of photography that
allows an image to be recorded in three dimensions.
Advantages:
1) Useful when storage space is premium.
2)Damage expense associated with transport of study
case.
Disadvantages:
1) Back of familiarity
2)Some views of teeth were poor.
13. It is a quantitative technique for measurement of
mineral loss 6.cm dental caries.
White spot formation has been attributed to the
effect of prolonged accumulation and retention 06
bacterial place on enamel surface adjacent to
appliance
Enamel demineralization induces
Minerals will be replaced by water.
Decrease in light path in tooth substance.
Decrease intensity of fluorescence in dematerialized
area.
14. Surface roughness is essential factor as it determines.
a) effectiveness of arch guided tooth movement.
b) corrosion behavior.
c) aesthetics of orthodontic components
Principal technique for determining surface roughness is
surface probilomety.
15. Laser welding –Two types
a) Conduction welding
B) Penetration welding
There are two common types
of laser technologies in use.
a) Co2 Laser
b) Solid state lasers
Laser welding is free from.
a) Insufficient joint resistance.
b) Possibility of joined elements to be defined by heat.
c) Diminishing of elements mechanical properties
when vast areas are heated.
d) Low corrosion resistance.
16. Used for following purpose.
1) Normal arch wire attachment is readily accomplished
and stimulated orthodonticial splints were early
fabricated.
2)A cuspid to cuspid lingual retainer & several space
maintainer.
3)Direct welding of formed arch wire to direct bond
pads & Orthodontic bands.
4)The attachment of auxiliaries & additional arch wire
brackets.
17. Laser irradiation causes surface roughening and
irregularity to a depth of 10 to 20 gm.
Laser etching is painless & does not involve vibration
or heat.
Surface produced by laser etching’s acid resistance.
Time taken – 20 – 25 sec
18. Choice of light source is critical
various light curing sources are
Halogem
Plasma arc
Argon laser
Light emitting diode units
Advantages
1. It offers rapid curing
2. Improves Physical Properties
Argon laser curing unit:
1) Same significant chairtime
2) Potential to confer demieralozation resistance to
enamel
3) Frequency of enamel fracture at debonding was far
19. One of clinician major concern when using ceramic
brackets is the risk of enamel damage at debonding.
Laser debonding is based an thermal softening is
bared on thermal softening of adhesive resin.
Laser degrade resins by thermal softening, thermal
ablation photo ablation.
Advantages:
Less time span – 4sec
De bonding force is less
Risk of enamel damage & bracket fracture is reduce
Heat produced is localized & Controlled.
20. Un expected bracket debonding is a real problem.
Laser structured base bracket mechanism provide
strongest tensile bond strength.
Porcelain surface treatment:
Co2 laser is well suited for treatment of porcelain material
because its emission wavelength is almost totally absorbed
by porcelain.
Better adhesion when compared to acid etching & sand
blasting.
21. During tooth movement high levels of prostaglandin
PGE2 and interleukin IL-1 Beta are found in PDL.
Increase in PGE2 & IL- Beta production was
significantly inhibited.
Post adjustment Pain:
Low level laser therapy is internationally accepted
design.
It is defined as laser treatment in which energy outpul is
low enough so as not to cause a rise in temperature of
treated tissue above 36.5o
c
22. Ga-Al-As diode laser irradiation significantly stimulate
bone regeneration in mid palatal suture.
It may be a great therapeutic benefit in inhibiting
relapse or shortening the retention period or both
Controlling growth of facial structures:
Lasers can be used to control growth and development
of facial structure especially condyle and mandible.
23. Laser irradiation can stimulate bone regeneration at
bone fracture and extraction site and increase rate of
orthodontic movement in rats as per studies by
kawaski & shimizu.
Prevention of Dental caries:
Use of Nd-YAG laser irradiation followed with
application of acidulated phosphate fluoride solution
acts as an effective method of caries control during
orthodontic tooth movement argon laser irradiation
gives protection against demineralization under acid
attack & reduces threshold ph at which dissolution
occurs.
24. Advantages:
Cost effective
Reduces treatment time.
Vastly improve esthetic results.
Procedure is done with little pain or bleeding.
Indication:
Gingival recontouring and sculpting.
Frenectomy
Access gingivectomy.
Gingivectomy of hypertrophic tissue.
Operculum removal.
