elastics orthodontics / fixed orthodontics courses

LASTICS IN ORTHODONTICSwww.indiandentalacademy.comwww.indiandentalacademy.com

CONTENTSCONTENTS
1.1. INTRODUCTION.INTRODUCTION.
2.2. TERMINOLOGYTERMINOLOGY
3.3. HISTORY OF ELASTICS ANDHISTORY OF ELASTICS AND
ELASTOMERICSELASTOMERICS
4.4. PROPERTIES OF ELASTICS ANDPROPERTIES OF ELASTICS AND
ELASTOMERICSELASTOMERICS
5. CLASSIFICATION OF ELASTICS5. CLASSIFICATION OF ELASTICS
6.6. ANALYSIS OF ELASTIC FORCEANALYSIS OF ELASTIC FORCE
6.6. FORCE DEGRADATIONFORCE DEGRADATION
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7. ELASTIC ERRORS7. ELASTIC ERRORS
9.TYPES OF ELASTICS9.TYPES OF ELASTICS
10. PRE STRETCHED ELASTICS10. PRE STRETCHED ELASTICS
11. FLUORIDE RELEASE FROM11. FLUORIDE RELEASE FROM
ORTHODONTIC ELASTIC CHAINORTHODONTIC ELASTIC CHAIN
12. ELASTIC LIGATURE V/S WIRE12. ELASTIC LIGATURE V/S WIRE
LIGATURESLIGATURES

13.COIL SPRING V/S ELASTIC13.COIL SPRING V/S ELASTIC
14.ORTHODONTIST’S PART14.ORTHODONTIST’S PART
IN PATIENT WEARING ELASTICSIN PATIENT WEARING ELASTICS
15.ARMAMENTARIUM15.ARMAMENTARIUM
16.INSTRUCTION FOR WEARING16.INSTRUCTION FOR WEARING
ELASTICSELASTICS
17.CONCLUSION17.CONCLUSION
18.REFERENCES18.REFERENCES

INTRODUCTIONINTRODUCTION
 Elastics and Elastomeric are routinely used asElastics and Elastomeric are routinely used as
a active component of orthodontic therapy.a active component of orthodontic therapy.
Elastics have been a valuable adjunct of anyElastics have been a valuable adjunct of any
orthodontic treatment for many years. Thereorthodontic treatment for many years. There
use, combined with good patient cooperation,use, combined with good patient cooperation,
provides the clinician with the ability to correctprovides the clinician with the ability to correct
both Antero-posterior and verticalboth Antero-posterior and vertical
discrepancies.discrepancies.

Both natural rubber and syntheticBoth natural rubber and synthetic
elastomers are widely used inelastomers are widely used in
orthodontic therapy. Naturally producedorthodontic therapy. Naturally produced
latex elastics are used in the Begglatex elastics are used in the Begg
technique to provide intermaxillarytechnique to provide intermaxillary
traction and intramaxillary forces.traction and intramaxillary forces.
Synthetic elastomeric materials in theSynthetic elastomeric materials in the
form of chains find their greatestform of chains find their greatest
application with edgewise mechanicsapplication with edgewise mechanics
where they are used to move the teethwhere they are used to move the teeth
along the arch wire.along the arch wire.www.indiandentalacademy.comwww.indiandentalacademy.com

The links of chain fit firmly under theThe links of chain fit firmly under the
wings of an edgewise bracket so thatwings of an edgewise bracket so that
chain elastomers also serve to replacechain elastomers also serve to replace
metal as the ligating force that holds themetal as the ligating force that holds the
arch wire to the teeth. Since they are soarch wire to the teeth. Since they are so
positively located on the brackets it ispositively located on the brackets it is
usual for the chains to remain in situusual for the chains to remain in situ
until replaced by the orthodontist at theuntil replaced by the orthodontist at the
next visit of the patient. This routinenext visit of the patient. This routine
differs from that usually followed fordiffers from that usually followed for
latex elastics, which are changed by thelatex elastics, which are changed by the
patient every one or two days.patient every one or two days.

The use of latex elastics in clinicalThe use of latex elastics in clinical
practice is predicted on force extensionpractice is predicted on force extension
values given by the manufactures forvalues given by the manufactures for
different sizes of elastics. The standarddifferent sizes of elastics. The standard
force index employed by suppliers indicatesforce index employed by suppliers indicates
that at three times the original lumen size,that at three times the original lumen size,
elastics will exert the force stated on theelastics will exert the force stated on the
package.package.
From a clinician view it would beFrom a clinician view it would be
mandatory not only to know the clinicalmandatory not only to know the clinical
aspect of these elastics but also their basicaspect of these elastics but also their basic
properties, in order to extract the most out ofproperties, in order to extract the most out ofwww.indiandentalacademy.comwww.indiandentalacademy.com

TERMINOLOGYTERMINOLOGY
ForceForce ::
It is defined as an act upon a bodyIt is defined as an act upon a body
that changes or tends to change thethat changes or tends to change the
state of rest, or the motion of that body.state of rest, or the motion of that body.
Though defined in units of Newtons it isThough defined in units of Newtons it is
usually measured in units of grams orusually measured in units of grams or
ounce.ounce.
ElasticElastic::
Is defined as the ability to return toIs defined as the ability to return to
its original length or shape after beingits original length or shape after being
stretchedstretched www.indiandentalacademy.comwww.indiandentalacademy.com

ElasticityElasticity::
The property of a substance thatThe property of a substance that
enables it to change its length, volumeenables it to change its length, volume
or shape in direct response to a forceor shape in direct response to a force
affecting such a change and recover itsaffecting such a change and recover its
original form upon the removal of theoriginal form upon the removal of the
force.force.
Elastic limitElastic limit::
The elastic limit is the maximum stressThe elastic limit is the maximum stress
which a material can endure withoutwhich a material can endure without
undergoing permanent deformationundergoing permanent deformationwww.indiandentalacademy.comwww.indiandentalacademy.com

Elastic Modulus or Modulus ofElastic Modulus or Modulus of
ElasticityElasticity: When a material is stressed: When a material is stressed
it is usually found that the stress isit is usually found that the stress is
usually proportional to the strain, sousually proportional to the strain, so
their ratio is constant. In other wordstheir ratio is constant. In other words
the material deforms linearly andthe material deforms linearly and
elastically. This can be represented byelastically. This can be represented by
the expressionthe expression
E = stress/strain.E = stress/strain.
ResilienceResilience:: [stored or spring energy][stored or spring energy]
Resilience represents the energyResilience represents the energy
storage capacity of a wire. It is stressedstorage capacity of a wire. It is stressed
not to exceed it proportional limitnot to exceed it proportional limit

 PlasticityPlasticity::
It is the property of any substance by whichIt is the property of any substance by which
the material can be molded into various formsthe material can be molded into various forms
and then hardened for commercial use.and then hardened for commercial use.
 RelaxationRelaxation::
It is defined as decrease in force valueIt is defined as decrease in force value
carried or transmitted over time with thecarried or transmitted over time with the
element maintained in a fixed activated stateelement maintained in a fixed activated state
of constant strain.of constant strain.
 VulcanizationVulcanization::
The process of heating sulphur-rubberThe process of heating sulphur-rubber
mixtures is known as vulcanization.mixtures is known as vulcanization.
1 ounce (oz) =1 ounce (oz) =www.indiandentalacademy.comwww.indiandentalacademy.com

HISTORY OF ELASTICSHISTORY OF ELASTICS
AND ELASTOMERICSAND ELASTOMERICS
 Elastomer is a general term that encompasses materialsElastomer is a general term that encompasses materials
that, after substantial deformation, rapidly return to theirthat, after substantial deformation, rapidly return to their
original dimensions.original dimensions.
 Natural rubber -the first known elastomer, used by theNatural rubber -the first known elastomer, used by the
ancient Incan and Mayan civilizations. It had limited useancient Incan and Mayan civilizations. It had limited use
because of its unfavorable temperature behavior andbecause of its unfavorable temperature behavior and
water absorption properties.water absorption properties.
 With the advent of vulcanization byWith the advent of vulcanization by Charles GoodyearCharles Goodyear
in 1839, uses for natural rubber greatly increased.in 1839, uses for natural rubber greatly increased. EarlyEarly
advocates of using natural latex rubber in orthodonticsadvocates of using natural latex rubber in orthodontics
were Baker, Case and Angle.were Baker, Case and Angle.

Natural RubberNatural Rubber
 When the early European explorers came to CentralWhen the early European explorers came to Central
and South America, they saw the Indians playing withand South America, they saw the Indians playing with
bouncing balls made of rubber.bouncing balls made of rubber.
 The South American Indians called the rubber treeThe South American Indians called the rubber tree
cahuchucahuchu,, weeping wood. The drops of latex oozingweeping wood. The drops of latex oozing
from the bark made them think of big white tears.from the bark made them think of big white tears.
 In 1770, the English chemistIn 1770, the English chemist Joseph PriestleyJoseph Priestley
discovered that the materials could be used as andiscovered that the materials could be used as an
eraser to rub out pencil marks. From this use we geteraser to rub out pencil marks. From this use we get
the name rubber.the name rubber.

 A French manA French man JMA StrangeJMA Strange in 1841in 1841
claimed that he used a rubber attached toclaimed that he used a rubber attached to
some hooks on the appliance surrounding thesome hooks on the appliance surrounding the
molars for retention.molars for retention.
 John TomesJohn Tomes in 1848 used the elasticsin 1848 used the elastics
springs with metal plates.springs with metal plates.

 Celvin CaseCelvin Case discussed the use ofdiscussed the use of
intermaxillary elastics at the Columbia Dentalintermaxillary elastics at the Columbia Dental
Congress. However in 1893Congress. However in 1893 Henry A BakerHenry A Baker
was credited with, originating the use ofwas credited with, originating the use of
intermaxillary elastics with rubber bands andintermaxillary elastics with rubber bands and
named it asnamed it as Baker AnchorageBaker Anchorage . .. . AngleAngle
in1902 described the technique before thein1902 described the technique before the
New York institute of Stomatology.New York institute of Stomatology.

Synthetic RubberSynthetic Rubber
 Synthetic rubber polymers developed fromSynthetic rubber polymers developed from
petrochemicals in the 1920’s have a weak molecularpetrochemicals in the 1920’s have a weak molecular
attraction consisting of primary and secondary bonds.attraction consisting of primary and secondary bonds.
 Elastomeric chains were introduced to dentalElastomeric chains were introduced to dental
profession in the 1960’s and have become integralprofession in the 1960’s and have become integral
part of orthodontic practice. They are used topart of orthodontic practice. They are used to
generate light continuous forces. They aregenerate light continuous forces. They are
inexpensive, relatively hygienic, easily applied andinexpensive, relatively hygienic, easily applied and
required no patient cooperation.required no patient cooperation.
 From here and there have been numerous advancesFrom here and there have been numerous advances
in manufacturing process which have let to ain manufacturing process which have let to a
significant importance in their properties, with thissignificant importance in their properties, with this
there has been greater application of these elastics inthere has been greater application of these elastics in
clinics in variety of uses.clinics in variety of uses.www.indiandentalacademy.comwww.indiandentalacademy.com

PROPERTIES OF ELASTICSPROPERTIES OF ELASTICS
AND ELASTOMERICSAND ELASTOMERICS
 Rubber is one of our most interesting and mostRubber is one of our most interesting and most
important raw materials.important raw materials. Natural rubberNatural rubber
comes from the juice of a tree.comes from the juice of a tree. SyntheticSynthetic
rubberrubber is made from chemicals.is made from chemicals.
 Rubber is especially useful for several reasons:-Rubber is especially useful for several reasons:-
 it holds airit holds air
 keeps out the moisturekeeps out the moisture
 does not readily conduct electricitydoes not readily conduct electricity ..
 But its chief importance to us is that it isBut its chief importance to us is that it is
elastic.elastic.

Natural RubberNatural Rubber
 Chemical analysis shows that about 30 to 35 percentChemical analysis shows that about 30 to 35 percent
of latex consists of pure rubber, water makes upof latex consists of pure rubber, water makes up
another 60 to 65 percent. The remainder consists ofanother 60 to 65 percent. The remainder consists of
small amount of other materials such as resins,small amount of other materials such as resins,
proteins, sugar and mineral matter. Latex spoilsproteins, sugar and mineral matter. Latex spoils
easily and must therefore be processed into crudeeasily and must therefore be processed into crude
rubber as soon as possible after it has beenrubber as soon as possible after it has been
tapped.This is done by separating the natural rubbertapped.This is done by separating the natural rubber
in the latex from water and other materials. About 99in the latex from water and other materials. About 99
percent of all natural rubber comes from the latex ofpercent of all natural rubber comes from the latex of
Hevea brasiliensisHevea brasiliensis . This is the tree that we call the. This is the tree that we call the
rubber tree.rubber tree.

 In 1860, another Englishman,In 1860, another Englishman, GrevilleGreville
Williams,Williams, heated some rubber and obtainedheated some rubber and obtained
a colourless liquid that he calleda colourless liquid that he called isopereneisoperene..
Each isoperene molecule contains fiveEach isoperene molecule contains five
carbon atoms and eight hydrogen atomscarbon atoms and eight hydrogen atoms
(C(C55HH88). The atom in the isoperene molecules). The atom in the isoperene molecules
always forms a definite pattern. Four of thealways forms a definite pattern. Four of the
carbon atoms form a chain. The fifth carboncarbon atoms form a chain. The fifth carbon
atom branches off from one of the carbons inatom branches off from one of the carbons in
the chain. Three hydrogen atoms surroundthe chain. Three hydrogen atoms surround
the fifth carbon atom to form a methyl group. :the fifth carbon atom to form a methyl group. :

The following chemical symbols show the arrangement of the
five carbon and eight hydrogen atoms in the isoperene
molecule
H (Methyl Group)
H C H
H H H
C=C C=C (Chain)
H H
In natural rubber thousands of tiny isoperene molecules link
together in a giant, chainlike molecule, the rubber molecule.

 Natural rubber has many unsaturated carbonNatural rubber has many unsaturated carbon
atoms. Oxygen atoms from the air graduallyatoms. Oxygen atoms from the air gradually
attach themselves to these carbon atoms.attach themselves to these carbon atoms.
This breaks down the rubber polymers so thatThis breaks down the rubber polymers so that
the rubber becomes brittle or soft and losesthe rubber becomes brittle or soft and loses
elasticity. The addition of antioxidants duringelasticity. The addition of antioxidants during
compounding prevents this action.compounding prevents this action.
 Scientists have not discovered all theScientists have not discovered all the
answers to the chemistry of rubber. Foranswers to the chemistry of rubber. For
example, they once believed that sulphurexample, they once believed that sulphur
atoms attached themselves to unsaturatedatoms attached themselves to unsaturated
carbon atoms during vulcanization. But thecarbon atoms during vulcanization. But the
sulphur reaction that makes rubber hard nowsulphur reaction that makes rubber hard now
seems more complicated than this. In manyseems more complicated than this. In many
other ways, the chemistry of natural rubberother ways, the chemistry of natural rubber
remains mystery.remains mystery.www.indiandentalacademy.comwww.indiandentalacademy.com

Synthetic rubberSynthetic rubber
Rubber like materials which are madeRubber like materials which are made
from chemicals were called syntheticfrom chemicals were called synthetic
rubbers because they were intended asrubbers because they were intended as
substitutes for natural rubber. Chemistssubstitutes for natural rubber. Chemists
use the word elastomer for anyuse the word elastomer for any
substances, including rubber, whichsubstances, including rubber, which
stretches easily to several times itsstretches easily to several times its
length, and returns to its original shape.length, and returns to its original shape.
Manufacturers group synthetic rubbersManufacturers group synthetic rubbers
into two classes: General-purpose andinto two classes: General-purpose and
special-purpose.special-purpose.

General purpose syntheticGeneral purpose synthetic
rubbers:rubbers:
The most important general purposeThe most important general purpose
rubber is styrene-butadiene rubber (SBR).rubber is styrene-butadiene rubber (SBR).
It usually consists of about three partsIt usually consists of about three parts
butadiene and one part styrene. Butadiene,butadiene and one part styrene. Butadiene,
a gas, is made from petroleum. It must bea gas, is made from petroleum. It must be
compressed or condensed into liquid formcompressed or condensed into liquid form
for use in making rubber. Styrene is afor use in making rubber. Styrene is a
liquid made from coal tar or petroleum.liquid made from coal tar or petroleum.
Special purpose rubbers:Special purpose rubbers:
Contact with petrol, oils, sunlight and airContact with petrol, oils, sunlight and air
harms natural rubber. Special-purposeharms natural rubber. Special-purpose
synthetic rubbers resist these “enemies”synthetic rubbers resist these “enemies”
better than natural rubber or SBR do. Alsobetter than natural rubber or SBR do. Also
some of these special-purpose rubbers havesome of these special-purpose rubbers havewww.indiandentalacademy.comwww.indiandentalacademy.com

 Special-purposeSpecial-purpose
rubbers includerubbers include
 butyl rubberbutyl rubber
 cispolyisoperenecispolyisoperene
rubberrubber
 neoprene rubberneoprene rubber
 nitrile rubbernitrile rubber
 polysulphidepolysulphide
rubbersrubbers
 polyurethanepolyurethane
rubbersrubbers
 silicon rubbersilicon rubber
 ethylene-propyleneethylene-propylene
rubbersrubbers
 fluorocarbonfluorocarbon
rubbersrubbers


 Most of the elastics currently used in orthodontics areMost of the elastics currently used in orthodontics are
made up of polyurethane.made up of polyurethane.
 Polyurethane rubbers resist heat and withstandPolyurethane rubbers resist heat and withstand
remarkable stresses and pressures.. Polyurethaneremarkable stresses and pressures.. Polyurethane
foams come dense to light. The ingredients offoams come dense to light. The ingredients of
polyurethane rubbers include ethylene, propylene,polyurethane rubbers include ethylene, propylene,
glycols, adipic acid, and di-isocyanates.glycols, adipic acid, and di-isocyanates.
 It has got an excellent strength and resistance toIt has got an excellent strength and resistance to
abrasion when compared with natural rubber. Theyabrasion when compared with natural rubber. They
tend to permanently distort, following long periods oftend to permanently distort, following long periods of
time in the mouth and often lose their elastictime in the mouth and often lose their elastic
properties. This is mainly used for elastic ligatures.properties. This is mainly used for elastic ligatures.

CLASSIFICATION OFCLASSIFICATION OF
ELASTICSELASTICS
Elastics can be classified inElastics can be classified in
many ways. According tomany ways. According to
the material, theirthe material, their
availability, there uses andavailability, there uses and
force.force.

ACCORDING TO THE MATERIALACCORDING TO THE MATERIAL
Latex Elastics:Latex Elastics:
These are made up of natural rubberThese are made up of natural rubber
materials, obtained from plants, thematerials, obtained from plants, the
chemical structure of natural rubber is 1,chemical structure of natural rubber is 1,
4 polyisoprene.4 polyisoprene.
Synthetic elastics:Synthetic elastics:
These are polyurethane rubber containsThese are polyurethane rubber contains
urethane linkage. This is synthesized byurethane linkage. This is synthesized by
extending a polyester or a polyether glycol orextending a polyester or a polyether glycol or
polyhydrocarbon with a diisocynate. Thesepolyhydrocarbon with a diisocynate. These
are mainly used for elastic ligatures.are mainly used for elastic ligatures.

ACCORDING TO THEACCORDING TO THE
AVAILABILITYAVAILABILITY
Different makers have differentDifferent makers have different
sizes and force, and the coloursizes and force, and the colour
coding and the name is alsocoding and the name is also
different.different.

DIAMETER FORCECOLOUR
INCH MM GRAMS OUNCE
WHITE 1/8 3.2 56.8 2.0
RED 3/16 4.6 99.4 3.5
GREY 3/16 4.6 127.8 4.5
BLUE 1/ 4 6.4 99.4 3.5
ORANGE 1/ 4 6.4 127.8 4.5
YELLOW 5/16 7.9 56.8 2.0
GREEN 5/16 7.9 99.4 3.5
TAN 5/16 7.9 127.8 4.5
PINK 3/8 9.5 99.4 3.5
LAVENDER 3/8 9.5 127.8 4.5

DIAMETER FORCE
INCH MM GRAMS OUNCE
3/16 4.6 56.8 2.0
5/16 7.9 95.4 3.5
3/16 4.6 113.6 4.0
5/16 7.9 170.4 6.0
H
E
A
V
Y
.
E
L
A
S
T
I
C
S
5/16 7.9 227.2 8.0

ACCORDING TO THE USES.ACCORDING TO THE USES.
1) Intra oral1) Intra oral
2) Extra oral2) Extra oral

INTRAORAL ELASTICSINTRAORAL ELASTICS
1)1) CL I elastics or horizontal elastics orCL I elastics or horizontal elastics or
intramaxillary elastics or intra-archintramaxillary elastics or intra-arch
elastics:-elastics:-
•These extend with in each arch.
• This is used for the space closure and
to a certain extent; it can open
the bite also.
• It is placed from the molar tube to the
intramaxillary hook of canine of the
same side of the same arch.

. The force recommended is 1 ½ to 2 ½ oz for non
extraction cases and 2 to 4 oz. in extraction cases.

2) CL II Elastics / intermaxillary2) CL II Elastics / intermaxillary
elastics / interarch elasticselastics / interarch elastics
This is extended from the lower
molar teeth to upper cuspid which is
placed from lower molar tube to the
upper intermaxillary hook of the
same side.
They are primarily used to cause
Antero-posterior tooth changes that
aid in obtaining CL I cuspid
relationship from a CL II relationship

. If the lower second molar are banded it is best
to extend the elastic from the second molar to
the upper cuspid if they are to be used for over
two months of treatment.
If the elastics are used for 2 to 6 weeks only,
then one may extend them from the lower first
molar to upper cuspid teeth. This treatment
regimen minimizes the side effects from the
use of elastics (extrusion of the lower posterior
teeth and labial tipping of the lower anterior
teeth, lowering of anterior occlusal plain and
the creation of gummy smile). If any temporoma
dibular joint discomfort occurs elastic should be
discontinued at least temporarily.

In CL II elastics we can observe some following
important features:-
1. Light but direct force applied to both mandible and maxilla to
stimulate maxillary retardation and mandibular growth.
Negative side effects such as loss of maxillary anterior torque
can take place if elastic are used early in treatment.
2. Mandibular incisor advancement, especially with arch wire of
low stiffness and lingual tipping of maxillary anteriors.
3. Extrusion of mandibular molars.
4. Occlusal plane tipping.
5. It may exaggerate the increased lower anterior facial height.

The force recommended is 1 ½ to 2The force recommended is 1 ½ to 2
½ oz. in non extraction case and 2½ oz. in non extraction case and 2
to 4 in extraction casesto 4 in extraction cases

3) Class III elastics3) Class III elastics
• Class III elastics are exact opposite of the class II’s.
• They extended from upper molar to the lower cuspid.
• It is used in the treatment of CL III malocclusions.
• In some CL II cases also it is used to relieve edge
relationship of the anteriors.
• It is attached from the maxillary molar to mandibular
lateral incisor or canine.
• They promote extrusion of upper posterior teeth and
upper anteriors, along with lingual tipping of the lower
anteriors.

Indications:
1. To avoid advance maxillary dentition and or
retract the mandibular dentition.
2. To correct anterior cross bite.
3. Mandibular crowding in a non extraction case
in which it is desired to eliminate the crowding
without advancing the mandibular incisor
appreciably.
4. In deep bite, low angle, crowded case early
use of c1 III elastics will allow the bite open.

Recommended force is ¼” elastic with 3 ½ ozRecommended force is ¼” elastic with 3 ½ oz

4.ANTERIOR ELASTICS:
1. It is used to improve the over bite
relationship of incisor teeth.
2. Open bite up to 2mm may be corrected
with these elastics.
3. They may extend from the lower lateral
incisor to the upper laterals or central
incisor teeth or from the lower cuspid to
the upper laterals.
4. It is used in conjunction with a plain
arch wire for closing spaces between
anterior teeth. It produces a reciprocal
free tipping of anterior crowns, which
closes the spaces.

Anterior Elastics.Anterior Elastics.
(Force-1 to 2oz.)(Force-1 to 2oz.)

5)5) ZigzagZigzag ElasticsElastics
Aras AAras A et al 2001 they have done pilotet al 2001 they have done pilot
study of “The effect of zig zag elastics instudy of “The effect of zig zag elastics in
the treatment of CL II div 1 malocclusionthe treatment of CL II div 1 malocclusion
subjects with hypo and hyper divergentsubjects with hypo and hyper divergent
growth pattern”. The conclusion of thisgrowth pattern”. The conclusion of this
study can be summarized as follows.study can be summarized as follows.
 Zig zag elastics thus was used in the lastZig zag elastics thus was used in the last
stage of fixed appliance treatment of CL IIstage of fixed appliance treatment of CL II
malocclusion in growing patient weremalocclusion in growing patient were
effective in the correction of molareffective in the correction of molar
relationship. Establishing a goodrelationship. Establishing a good
intercuspation as well as improving sagittalintercuspation as well as improving sagittal
skeletal relationship.skeletal relationship.

Force recommended is 2.5 oz.Force recommended is 2.5 oz.

6] Cross Bite Elastics6] Cross Bite Elastics
•This is indicated in unilateral and
bilateral cross bites, to expand and
upright lower molars which have tipped
lingually.
• It is placed between the lingual aspect of
the lingually placed molar and the buccal
aspect of the opposing tooth.

Force recommended is 5-7 ounceForce recommended is 5-7 ounce

7) Cross Palate Elastics7) Cross Palate Elastics
•This is to correct the undesired expansion of the upper
molars, during third stage.
• This is placed between the lingual aspects of the upper
molars.
• Upper molar expansion during the 3rd
stage is usually
bilateral, the cross palate elastics is appropriate because the
force it exerts in pulling one molar lingually is equal and
opposite to the force it exerts in pulling the other lingually.

8) Diagonal Elastics (Midline8) Diagonal Elastics (Midline
elastics)elastics)
Force used is 1 ½ to 2 ½ ounces.Force used is 1 ½ to 2 ½ ounces.

9) Open Bite Elastics9) Open Bite Elastics
 These are used for the correction ofThese are used for the correction of
open bite.open bite.
 It can be carried out by a verticalIt can be carried out by a vertical
elastic, triangular or box elastic.elastic, triangular or box elastic.
 Vertical elastic runs between theVertical elastic runs between the
upper and lower brackets of eachupper and lower brackets of each
tooth.tooth.

10.Box elastics10.Box elastics
•Box elastics have a box shape configuration and
can be used in variety of situations to promote tooth
extrusion and improve intercuspation.
•Most commonly, they include the upper cuspid
and lateral incisor to the lower first bicuspid and
cuspid(CL II vector) or to the lower cuspid and
lateral incisors(CL III vector).
• All bicuspid teeth of one side can be extruded as
well.
•These are used to correct the open bite or to
decrease the anterior open bite.

Box ElasticsBox Elastics
Force used ¼” 6 oz or 3/16”Force used ¼” 6 oz or 3/16”
6 oz.6 oz.

•Triangular elastics aid in the
improvement of CL I cuspid intercuspation
and
• increase the over bite relationship
anteriorly by closing open bite in the
range of 0.5 to 1.5 mm.
• They extended from upper cuspid to the
lower cuspid and first bicuspid teeth.
• It is used for similar reasons of box
elastics, but including only 3 teeth
11.Triangular elastics:11.Triangular elastics:

Triangular ElasticsTriangular Elastics
Elastics of 1/8” 3 ½ oz isElastics of 1/8” 3 ½ oz is
used.used.

12)Vertical12)Vertical
Elastics(Spaghetti)Elastics(Spaghetti)
Force used is 3 ½ oz.Force used is 3 ½ oz.•This is useful in whom there is
difficulty in closing the bite, whether
anteriorly or posteriorly.
• This type of elastic is contraindicated
in malocclusions that were originally
characterized by a deep bite

13] M and W Elastics13] M and W Elastics
Force is ¾” 2 ounce.Force is ¾” 2 ounce.
•In an open bite or c1 III tendency some amount curve of spee
should have been placed in the lower arch. Therefore some
curve should be placed in the upper arch as well.
• The arch wire is sectioned distal to laterals or cuspids and up
and down elastics ( “M” with a tail) are worn.
• In class I case M or W without a tail is used. The upper and
lower arch wire is sectioned in which the teeth to be extruded.
•In class II vector ‘W’ with a tail is given.

14.Lingual elastics14.Lingual elastics
 This can be used as a supplement or a counterThis can be used as a supplement or a counter
balancing agent to buccal elastic force, there bybalancing agent to buccal elastic force, there by
increasing the efficiency of force distribution.increasing the efficiency of force distribution.
 Lingualy tipped lower molars can be uprighted by theLingualy tipped lower molars can be uprighted by the
use of class II elastics attached between to lingual hookuse of class II elastics attached between to lingual hook
of the lower molar and intermaxillary hook of upper archof the lower molar and intermaxillary hook of upper arch
wire on the same side.wire on the same side.
 Lingual elastics can be used as a substitute for buccalLingual elastics can be used as a substitute for buccal
elastics like CL I and CL II elastics, provided the archelastics like CL I and CL II elastics, provided the arch
wire should be tied back to the cuspid bracket.wire should be tied back to the cuspid bracket.

Lingual ElasticsLingual Elastics

15) Check Elastics15) Check Elastics
Check elastics can provide a potent mechanism for
overbite reduction, causing extrusion of maxillary
and mandibular molars and counteracting the
tendency of the anchor bends to tip the molars
distally plus aiding incisor intrusion.

16] Sling Shot Elastics( Molar16] Sling Shot Elastics( Molar
distalizing)distalizing)
Two hook on buccal and lingual side ofTwo hook on buccal and lingual side of
the molar to be incorporated in the acrylicthe molar to be incorporated in the acrylic
plate to hold the elastic. The elastic isplate to hold the elastic. The elastic is
stretched at the mesial aspect of molar tostretched at the mesial aspect of molar to
distalize it.distalize it.

17)Elastics in removable17)Elastics in removable
applianceappliance
 Elastics in conjunction with the removalElastics in conjunction with the removal
appliance are used for the movement ofappliance are used for the movement of
single and groups of teeth, and forsingle and groups of teeth, and for
intermaxillary traction.intermaxillary traction.
 It can be used to move impacted canine toIt can be used to move impacted canine to
proper place along with the Hawleyproper place along with the Hawley
appliance.appliance.
 The use of elastics in moving the canineThe use of elastics in moving the canine
distally along with screw appliances.distally along with screw appliances.
 The acrylic plates covering the premolarsThe acrylic plates covering the premolars
and molars and tuberosities for bodilyand molars and tuberosities for bodily
anchorage.anchorage.

18) Other elastics18) Other elastics::
Asymmetrical elastics:Asymmetrical elastics:
They are usually CL II on one sideThey are usually CL II on one side
and CL III on other side. They are used toand CL III on other side. They are used to
correct dental asymmetries. If a significantcorrect dental asymmetries. If a significant
dental midline deviation is present (2mm ordental midline deviation is present (2mm or
more), an anterior elastic from upper lateralmore), an anterior elastic from upper lateral
to the lower contralateral lateral incisorto the lower contralateral lateral incisor
should also be used.should also be used.
Finishing elastics:Finishing elastics:
Are used at the end of the treatment for finalAre used at the end of the treatment for final
posterior settling.posterior settling.
Force recommended ¾” or 2 ozForce recommended ¾” or 2 oz

ACCORDING TO THEACCORDING TO THE
FORCEFORCE
High PullHigh Pull
Ranges from 1/8” (3.2mm) to 3/8”Ranges from 1/8” (3.2mm) to 3/8”
(9.53mm). It gives 71 gm force (2 ½ oz)(9.53mm). It gives 71 gm force (2 ½ oz)
Medium PullMedium Pull
Ranges from 1/8” (3.2mm) 3/8” (9.53 mm)Ranges from 1/8” (3.2mm) 3/8” (9.53 mm)
it gives 128gm or 4 ½ oz force.it gives 128gm or 4 ½ oz force.
Heavy pullHeavy pull
Ranges from1/8”(3.2mm) 3/8”(9.53 mm) ItRanges from1/8”(3.2mm) 3/8”(9.53 mm) It
gives 184gm or 6 1/2oz force.gives 184gm or 6 1/2oz force.

Elastic separatorsElastic separators
Elastic separatorsElastic separators
Dumbell separatorDumbell separator

TYPES OF ELASTICSTYPES OF ELASTICS
INTRA ORAL ELASTICS:INTRA ORAL ELASTICS:
It can be of light, medium or heavyIt can be of light, medium or heavy

EXTRA ORAL ELASTICSEXTRA ORAL ELASTICS::
Heavy elastics and plasticHeavy elastics and plastic
chain are used with the head gearchain are used with the head gear

E-LINKE-LINK ::
It is used as intermaxillary classIt is used as intermaxillary class
II and class III applications. It isII and class III applications. It is
available in different lengthsavailable in different lengths

LIG-A-RING:LIG-A-RING:
It is used for individual ligation of theIt is used for individual ligation of the
tooth. It can be used in place of conventionaltooth. It can be used in place of conventional
ligature ties in straight wire therapy and forligature ties in straight wire therapy and for
cuspid ties in Begg. It is of 1.5 – 2 mm incuspid ties in Begg. It is of 1.5 – 2 mm in
diameter.diameter.

TIP EDGE RINGS:TIP EDGE RINGS:
It can control and hold the desiredIt can control and hold the desired
degree of mesiodistal inclination. Thedegree of mesiodistal inclination. The
cross bar can give up-righting forces.cross bar can give up-righting forces.

E-CHAIN:E-CHAIN:
It is used for continuous ligation andIt is used for continuous ligation and
consolidation etc. It is available in 3 types.consolidation etc. It is available in 3 types.
Small (continuous)Small (continuous)
Medium (short)Medium (short)
Large (long)Large (long)

POWER THREAD: (ELASTICPOWER THREAD: (ELASTIC
LIGATURE)LIGATURE)
This is polyurethane thread, used forThis is polyurethane thread, used for
rotating, extruding, losing minor spacingrotating, extruding, losing minor spacing
and to consolidateand to consolidate

ELASTELAST --O CHAIN:O CHAIN:
It is used for consolidation of arches.It is used for consolidation of arches.
It gives a light continuous traction force.It gives a light continuous traction force.

ELASTIC THREAD:ELASTIC THREAD:
This is an elastic ligature covered with silkThis is an elastic ligature covered with silk
or nylon. The nylon fibers is there to resistor nylon. The nylon fibers is there to resist
the unravelling and protect the latex core. Itthe unravelling and protect the latex core. It
is available in 3 types. It is used for rotationis available in 3 types. It is used for rotation
correction, traction etc, both with fixed andcorrection, traction etc, both with fixed and
removable appliance.removable appliance.
LightLight
MediumMedium
HeavyHeavy

SEPARATING RINGS:SEPARATING RINGS:
It gives a continuous force duringIt gives a continuous force during
contact opening.contact opening.
.Small – used in anterior region.Small – used in anterior region
.Large – used in posterior region.Large – used in posterior region

ROTATION WEDGES :ROTATION WEDGES :
It acts as a fulcrum between wire andIt acts as a fulcrum between wire and
bracket to correct the rotation. It isbracket to correct the rotation. It is
ligated to the tie wing of the bracket.ligated to the tie wing of the bracket.

PLASTIC CHAIN:PLASTIC CHAIN:
It is used extraoraly along with headIt is used extraoraly along with head
gear, for the orthopedic correction usinggear, for the orthopedic correction using
heavy forces.heavy forces.

ANALYSIS OF ELASTICANALYSIS OF ELASTIC
FORCEFORCE
Force produced by elastics on a tooth orForce produced by elastics on a tooth or
teeth depends on its magnitude. Theteeth depends on its magnitude. The
stress produced depends on the site ofstress produced depends on the site of
application, distribution through theapplication, distribution through the
periodontal ligament and direction, length,periodontal ligament and direction, length,
diameter and contour of root, alveolardiameter and contour of root, alveolar
process, tooth rotation and health, ageprocess, tooth rotation and health, age
and above all the co-operation of theand above all the co-operation of the
patientpatient

CL I elastic traction is judiciouslyCL I elastic traction is judiciously
combined with strong anchor bend.combined with strong anchor bend.
Deliberate consideration of anchorageDeliberate consideration of anchorage
conservation is essential, because theconservation is essential, because the
resultant of the retractive and intrusiveresultant of the retractive and intrusive
forces that lies distant to the maxillaryforces that lies distant to the maxillary
molars will induce adverse movementsmolars will induce adverse movements
or anchorage loss of the maxillaryor anchorage loss of the maxillary
molars.molars.
 Intermaxillary elastic force exertsIntermaxillary elastic force exerts
pressure on the incisor in a verticalpressure on the incisor in a vertical
direction bringing them intodirection bringing them into
supraocclusion or accentuatingsupraocclusion or accentuating
supraocclusion already present. Tiltingsupraocclusion already present. Tilting
of anchor teeth may also occur.of anchor teeth may also occur.

 The amount of light force exerted by theThe amount of light force exerted by the
elastic is at an optimal level to tip the anteriorelastic is at an optimal level to tip the anterior
crowns backward but a minimal level to movecrowns backward but a minimal level to move
the lower molars forward bodily. Elastic forcethe lower molars forward bodily. Elastic force
received by the molars and anteriors arereceived by the molars and anteriors are
equal and opposite, the resistance is notequal and opposite, the resistance is not
equal. So the crown tipping is relatively rapidequal. So the crown tipping is relatively rapid
and bodily movements are slow.and bodily movements are slow.
 A continuous force can bring about rapidA continuous force can bring about rapid
intrusive movement. Each anterior tooth willintrusive movement. Each anterior tooth will
intrude by a force as light as 20 to 30 gms.intrude by a force as light as 20 to 30 gms.
The light force produces very shortThe light force produces very short
hyalinizations periods and the anterior teethhyalinizations periods and the anterior teeth
will be intruded quite rapidly.will be intruded quite rapidly.www.indiandentalacademy.comwww.indiandentalacademy.com

FORCE DEGRADATIONFORCE DEGRADATION
 Relaxation is defined as a decrease in forceRelaxation is defined as a decrease in force
value carried or transmitted over time with thevalue carried or transmitted over time with the
element maintained in a fixed activated stateelement maintained in a fixed activated state
of constant strain.of constant strain.
 The force decay under constant forceThe force decay under constant force
application to latex elastic, polymer chainsapplication to latex elastic, polymer chains
and tied loops showed that the greatestand tied loops showed that the greatest
amount of force decay occurred during theamount of force decay occurred during the
first three hours in water bath. The forcefirst three hours in water bath. The force
remained relatively the same throughout theremained relatively the same throughout the
rest of the periodrest of the period..

 K.A. Russell et al 2001 conducted the studyK.A. Russell et al 2001 conducted the study
on the assessment of mechanical propertieson the assessment of mechanical properties
of latex and non latex orthodontic elastics.of latex and non latex orthodontic elastics.
 So there are few general conclusions thatSo there are few general conclusions that
can be drawn and applied clinically to allcan be drawn and applied clinically to all
elastic types. Although all of elastics met theelastic types. Although all of elastics met the
Australian standard for breaking force thereAustralian standard for breaking force there
was trend towards non latex elastics havingwas trend towards non latex elastics having
lower breaking force than the latex elasticslower breaking force than the latex elastics

After an exhaustive review of theAfter an exhaustive review of the
literature regarding elastomeric chain, itliterature regarding elastomeric chain, it
can be said that most marketedcan be said that most marketed
elastomeric chains generally loses 50%elastomeric chains generally loses 50%
to 70% of their initial force during theto 70% of their initial force during the
first day of load application. At the endfirst day of load application. At the end
of three weeks they retained only 30 toof three weeks they retained only 30 to
40% of original force40% of original force

ELASTIC ERRORSELASTIC ERRORS
Latex allergyLatex allergy::
Allergies to the latex proteins are increasingAllergies to the latex proteins are increasing
which has implication for dental practitioners becausewhich has implication for dental practitioners because
latex is ubiquitous in dental environment.latex is ubiquitous in dental environment.
K. A. RusselK. A. Russel 2001 - reaction to the latex2001 - reaction to the latex
materials have become more prevalent and bettermaterials have become more prevalent and better
recognized- since 1988 adoption of universalrecognized- since 1988 adoption of universal
precautions. Only 3 reports have been cited in theprecautions. Only 3 reports have been cited in the
literature relating latex allergies to orthodonticliterature relating latex allergies to orthodontic
treatment. 2 of these studies related the allergictreatment. 2 of these studies related the allergic
reactions to use of latex gloves, and 3reactions to use of latex gloves, and 3rdrd
report relatedreport related
to the development of stomatitis with acute swellingsto the development of stomatitis with acute swellings
and erythematous buccal lesions to the use ofand erythematous buccal lesions to the use of
orthodontic elasticsorthodontic elasticswww.indiandentalacademy.comwww.indiandentalacademy.com

Staining of elasticsStaining of elastics
Elastomeric materials do stain from certainElastomeric materials do stain from certain
food such as mustard.food such as mustard.
The attempt to solve this problem byThe attempt to solve this problem by
masking with metallic colour inclusions reduces themasking with metallic colour inclusions reduces the
strength and elasticity. It is because of the differencestrength and elasticity. It is because of the difference
in the resilient properties.in the resilient properties.
A study regarding staining in 1990 by Kenneth K.A study regarding staining in 1990 by Kenneth K.
K. Lew divided into 3 categories.K. Lew divided into 3 categories.
No staining: - With coco cola presumably mostNo staining: - With coco cola presumably most
colorless food stuffs.colorless food stuffs.
Gradual staining: - With chocolate drink, red wine,Gradual staining: - With chocolate drink, red wine,
tomato ketchup.tomato ketchup.
Rapid staining: - With coffee and tea.Rapid staining: - With coffee and tea.

STORAGESTORAGE
According to theAccording to the
manufactures the orthodonticmanufactures the orthodontic
elastics should be stored in theelastics should be stored in the
refrigerator, because increasedrefrigerator, because increased
atmospheric temperature for aatmospheric temperature for a
long period will decrease thelong period will decrease the
strength. Keeping in refrigeratorstrength. Keeping in refrigerator
(cool and dry) will give long shelf(cool and dry) will give long shelf
lifelife..

PRE STRETCHING OF ELASTICSPRE STRETCHING OF ELASTICS
Allen. K. Wong suggested in 1976 that theAllen. K. Wong suggested in 1976 that the
elastomeric materials need to pr-stretchedelastomeric materials need to pr-stretched
1/31/3rdrd
of their length to pre stress the molecularof their length to pre stress the molecular
polymer chain. This procedure will increasepolymer chain. This procedure will increase
the length of a material. If the material is overthe length of a material. If the material is over
stretched a slow set will occur but will go backstretched a slow set will occur but will go back
to original state in time. If the material is overto original state in time. If the material is over
stretched to near breaking point, over andstretched to near breaking point, over and
over again permanent plastic deformation willover again permanent plastic deformation will
occuroccur..
 These means that the initial force may come toThese means that the initial force may come to
an effect during an pre stretched process. Soan effect during an pre stretched process. So
when it is in use it will give more stable force.when it is in use it will give more stable force.www.indiandentalacademy.comwww.indiandentalacademy.com

FLUORIDE RELEASE FROMFLUORIDE RELEASE FROM
ORTHODONTIC ELASTICORTHODONTIC ELASTIC
CHAINCHAIN
Plaque accumulation around the fixedPlaque accumulation around the fixed
orthodontic appliance will cause dental andorthodontic appliance will cause dental and
periodontal decease.periodontal decease.
 Decalcification can be avoided by mechanicalDecalcification can be avoided by mechanical
removal of plaque or by topical fluorideremoval of plaque or by topical fluoride
application or with a mechanical sealant layerapplication or with a mechanical sealant layer
 Controlled fluoride release device (CFRD) haveControlled fluoride release device (CFRD) have
been in use since 1980’s. in such device a co-been in use since 1980’s. in such device a co-
polymer membrane allows a reservoir of fluoridepolymer membrane allows a reservoir of fluoride
ions to migrate into oral environment rate.ions to migrate into oral environment rate.www.indiandentalacademy.comwww.indiandentalacademy.com

The study was designed to a stannousThe study was designed to a stannous
fluoride release from a fluoridefluoride release from a fluoride
impregnated elastic power chain.impregnated elastic power chain.
The delivery of stannous fluoride by meansThe delivery of stannous fluoride by means
of power chain would presumably reduceof power chain would presumably reduce
count and inhibit demineralization.count and inhibit demineralization.
(An average of 0.025mg of fluoride is(An average of 0.025mg of fluoride is
necessary for reminerilization).necessary for reminerilization).
But this protection is only temporary and ofBut this protection is only temporary and of
a continued exposure needs, the elastica continued exposure needs, the elastic
should be replaced at weekly intervals. Theshould be replaced at weekly intervals. The
force degradation property will be higherforce degradation property will be higher
with the fluorinated elastic chain.with the fluorinated elastic chain.

ELASTIC LIGATURES VsELASTIC LIGATURES Vs
WIRE LIGATURESWIRE LIGATURES
 Elastic ligature may be a substitute for the wireElastic ligature may be a substitute for the wire
ligatures in most situations.ligatures in most situations.
 Elastic ligatures will give an easy work to the doctorElastic ligatures will give an easy work to the doctor
and since no sharp ends it will be more acceptable byand since no sharp ends it will be more acceptable by
the patient.the patient.
 In rotation control, higher force levels thanIn rotation control, higher force levels than
elastomeric materials is required. The brackets inelastomeric materials is required. The brackets in
rotation cases the partial engagement of the arch wirerotation cases the partial engagement of the arch wire
will be difficult with elastic ligature, so in these caseswill be difficult with elastic ligature, so in these cases
wire ligature are advised.wire ligature are advised.

When the sliding of a bracket on theWhen the sliding of a bracket on the
arch wire is needed, it is advisable toarch wire is needed, it is advisable to
use elastic ligature because of itsuse elastic ligature because of its
smoothness.smoothness.
The strength and inflexibility of wireThe strength and inflexibility of wire
ligatures may also provide moreligatures may also provide more
secured ligation. The relatively lowsecured ligation. The relatively low
strength of the elastic ligature is itsstrength of the elastic ligature is its
major disadvantage.major disadvantage.
Ligature wire can transfer elasticLigature wire can transfer elastic
force from arch wire to tooth and forforce from arch wire to tooth and for
holding the engagement of the archholding the engagement of the arch
wire in the bracket.wire in the bracket.

COIL SPRINGS VsCOIL SPRINGS Vs
ELASTICSELASTICS
 To overcome the drawbacks of elastomericTo overcome the drawbacks of elastomeric
material,material, Andrew L. SouisAndrew L. Souis in 1994 conducted ain 1994 conducted a
study NiTi coil springs and elastics.study NiTi coil springs and elastics.
 This study shows the following:-This study shows the following:-
- NiTi coil springs have been shown to produce aNiTi coil springs have been shown to produce a
constant force over varying length with no decay.constant force over varying length with no decay.
- NiTi coil spring produced nearly twice rapid a rateNiTi coil spring produced nearly twice rapid a rate
of tooth movement as conventional elastics.of tooth movement as conventional elastics.
- No patient co-operation needed.No patient co-operation needed.
- Coil springs can stretch as much as 500% with outCoil springs can stretch as much as 500% with out
permanent deformation.permanent deformation.
 The force delivered is 90 to 100gm.The force delivered is 90 to 100gm.

ORTHODONTIST’S PART INORTHODONTIST’S PART IN
PATIENT WEARINGPATIENT WEARING
ELASTICSELASTICS
 Educate the patient to wear the elasticsEducate the patient to wear the elastics
continuously except while brushing andcontinuously except while brushing and
replacing. Occasionally there may be somereplacing. Occasionally there may be some
exceptions.exceptions.
 Instruct the patient carefully where theInstruct the patient carefully where the
elastics are to be attached and have him toelastics are to be attached and have him to
do so before you.do so before you.
 Every visit check whether the patient isEvery visit check whether the patient is
wearing elastics, properly or not.wearing elastics, properly or not.
 Make sure that the patient can place hisMake sure that the patient can place his
elastics easily and that they remain in place.elastics easily and that they remain in place.

Check whether the hooks, pins, tubes,Check whether the hooks, pins, tubes,
cleats are easily accessible and remove allcleats are easily accessible and remove all
sharp edges that may cause breakage ofsharp edges that may cause breakage of
elastics.elastics.
Caution the patient not to allow the lowerCaution the patient not to allow the lower
jaw to come forward in response to thejaw to come forward in response to the
pulling force exerted by CL II elastics. Bepulling force exerted by CL II elastics. Be
sure that the patient closes in the propersure that the patient closes in the proper
retruded position.retruded position.
It is most important to impress upon theIt is most important to impress upon the
patient and the parents, that if there is anypatient and the parents, that if there is any
difficulty in wearing elastics it should bedifficulty in wearing elastics it should be
informed to your office immediately.informed to your office immediately.

Dispense sufficient amount of elasticsDispense sufficient amount of elastics
required till the next visit.required till the next visit.
Do not increase elastic force for a patientDo not increase elastic force for a patient
who shows unsatisfactory progress, beforewho shows unsatisfactory progress, before
making sure that he is actually wearing themaking sure that he is actually wearing the
elastics already prescribed.elastics already prescribed.

ARMAMENTARIUMARMAMENTARIUM
Dontrix GaugeDontrix Gauge:-:-
It is used to determine proper size elasticIt is used to determine proper size elastic
for each application by measuring thefor each application by measuring the
force. Measuring range is 28gm – 450gm.force. Measuring range is 28gm – 450gm.

Stress Gauge (correx Gauge):-Stress Gauge (correx Gauge):-
The measuring range is 25-250gm or 100-The measuring range is 25-250gm or 100-
500gms or 200 – 1000 gm.500gms or 200 – 1000 gm.

Elastic separator placing pliers:-Elastic separator placing pliers:-
Pliers with the limit for excess expansion.Pliers with the limit for excess expansion.
Rounded beak protects patient’s softRounded beak protects patient’s soft
tissue. It can be used with large and smalltissue. It can be used with large and small
ringsrings

Mathieu ForcepsMathieu Forceps :-:-
It is used for placing all types ofIt is used for placing all types of
elastomers. It has got a slip free graspingelastomers. It has got a slip free grasping
and quick release ratchets for fastand quick release ratchets for fast
operation.operation.
Twirl on ligatureTwirl on ligature :-:-
It is used for placing elastomeric modulesIt is used for placing elastomeric modules
and can be preloaded.and can be preloaded.

Module removerModule remover
Double ended instrument for removingDouble ended instrument for removing
modules from the bracket.modules from the bracket.
Mosquito forcesMosquito forces
Having curved delicate serrated tips forHaving curved delicate serrated tips for
applying modulesapplying modules

Orthodontic wrenchOrthodontic wrench
It is a double ended plasticIt is a double ended plastic
instrument for the use of attachinginstrument for the use of attaching
and elastics by patient himselfand elastics by patient himself
Elastic positioner for powerElastic positioner for power
modulesmodules

CONCLUSIONCONCLUSION
 To put it in a nut shell elastics is a primeTo put it in a nut shell elastics is a prime
consideration in orthodontics.consideration in orthodontics.
 Elastics are one of the most versatile materialElastics are one of the most versatile material
available to the orthodontist.available to the orthodontist.
 Its an invaluable tool of the orthodontistIts an invaluable tool of the orthodontist
armamentarium.armamentarium.
 An orthodontist who does not exploit theseAn orthodontist who does not exploit these
materials to the fullest is not doing justice to thematerials to the fullest is not doing justice to the
patient. As a matter of fact I would think that it ispatient. As a matter of fact I would think that it is
all but not impossible to practice in this branch ofall but not impossible to practice in this branch of
dentistry without this material.dentistry without this material.www.indiandentalacademy.comwww.indiandentalacademy.com

T
H
A
N
K
Y
O
U

 Bishara Samir E. and Anderson George F., “ABishara Samir E. and Anderson George F., “A
comparison of time recomparison of time re::
 lated forces between plastic alastics”. Angle Orthod.lated forces between plastic alastics”. Angle Orthod.
1970; 40; 319-328.1970; 40; 319-328.
 Brantley William A.“Effects of pre-stretching on forceBrantley William A.“Effects of pre-stretching on force
degradation characteristics of plastic modules”. Angledegradation characteristics of plastic modules”. Angle
Orthod. 1979; 49; 37-43.Orthod. 1979; 49; 37-43.
 Bruno W Kwapis and John E. Knox. “Extrusion of teethBruno W Kwapis and John E. Knox. “Extrusion of teeth
by elastics”. J Am Dent Assoc.1972; 84; 629 – 630.by elastics”. J Am Dent Assoc.1972; 84; 629 – 630.
 David L. Baty, “Force delivery property of coloredDavid L. Baty, “Force delivery property of colored
elastomeric modules”. Am J Orthod Dentofac Orthop.,elastomeric modules”. Am J Orthod Dentofac Orthop.,
1994; 106; 40-46.1994; 106; 40-46.
 David L. Baty, “ Synthetic Elastomeric chains a LiteratureDavid L. Baty, “ Synthetic Elastomeric chains a Literature
Review” Am J Orthod Dentofac Orthop.1994:105:536-42.Review” Am J Orthod Dentofac Orthop.1994:105:536-42.
 Dermaut L. R. and Breeden L. “The effects of CL IIDermaut L. R. and Breeden L. “The effects of CL II
elastic force on a dry skull measured by hylographicelastic force on a dry skull measured by hylographic
interferometry.” Am J Orthod. 1981; 79; 297-304.interferometry.” Am J Orthod. 1981; 79; 297-304.
 Fletcher G.G.T. “The Begg appliance and technique.Fletcher G.G.T. “The Begg appliance and technique.
London: Wright PSG: 1981.London: Wright PSG: 1981.
REFERENCES:

 Alexander R.G., “ The Alexander discipline”. USA; OrmcoAlexander R.G., “ The Alexander discipline”. USA; Ormco
Corporation;1986.Corporation;1986.
 Anthony D. , Viazi S., “Atlas Of Orthodontics- Principles andAnthony D. , Viazi S., “Atlas Of Orthodontics- Principles and
clinical application” W. B Saunders Company, 1993clinical application” W. B Saunders Company, 1993
 Aras. A et al “The zig zag elastics in the CL II div 1Aras. A et al “The zig zag elastics in the CL II div 1
malocclusion. Subject with hypo and hyper divergent growthmalocclusion. Subject with hypo and hyper divergent growth
pattern, a pilot study , Eur J orthod.: 2001; 23; 393-402.pattern, a pilot study , Eur J orthod.: 2001; 23; 393-402.
 Asbell M. B., “A brief history of orthodontist”. Am J OrthodAsbell M. B., “A brief history of orthodontist”. Am J Orthod
Dentofac Orthop. 1990; 98; 176-182, 206-213..Dentofac Orthop. 1990; 98; 176-182, 206-213..
 Begg P. R. and Peter C. Kessling; “The Begg OrthodonticBegg P. R. and Peter C. Kessling; “The Begg Orthodontic
theory and technique”; London; W. B. Saunders Co; 1977.theory and technique”; London; W. B. Saunders Co; 1977.
 Bell Walter R., “A study of applied force as related to the use ofBell Walter R., “A study of applied force as related to the use of
elastics and coil springs. Angle Orthod. 1951; 21; 151-154.elastics and coil springs. Angle Orthod. 1951; 21; 151-154.
 Bertl Wolfgang. H. and Droschl Helmut, “Forces produced byBertl Wolfgang. H. and Droschl Helmut, “Forces produced by
orthodontic elastics as a function of timeorthodontic elastics as a function of time and distance extended. Eur Jand distance extended. Eur J
Orthod. 1986; 8; 198-201.Orthod. 1986; 8; 198-201.
 Frank G. “Contact stomatitis resulting from the use ofFrank G. “Contact stomatitis resulting from the use of
orthodontic rubber elastics”. J Am Dent Assoc. 1974;orthodontic rubber elastics”. J Am Dent Assoc. 1974;
88; 1030-1031.88; 1030-1031.

 Graber T.M. and Swain B.F., “Current orthodontic conceptsGraber T.M. and Swain B.F., “Current orthodontic concepts
and techniques”. second edition. Toronto; W.B. Soundersand techniques”. second edition. Toronto; W.B. Sounders
company; 1975.company; 1975.
 Graber T. M and Bedrich Neuman, “Removable orthodonticGraber T. M and Bedrich Neuman, “Removable orthodontic
appliances”, second edition London; W.B. sounders company;appliances”, second edition London; W.B. sounders company;
1984.1984.
•Joseph V.P. “Fluoride release from
orthodontic elastic chain”. J.Clin Orthod. 1993;
26; 101-105.
•Kenneth K.K Lew, “Staining of clear
elastomeric modules from certain-foods”.
J.Clin Orthod. 1990; 24; 472-474.
•Sonis. Andrew L. “comparison of NiTi
coil springs Vs elastics in canine
retraction”. J.Clin Orthod. 1994; 28; 293
– 295.
•Taloumis Louis et al; “Instructions for wearing
elastics”; J. Clin Orthod; 1995 ; 25; 49;.

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