Upper 1st or 2nd molar hook to the upper canine hook. Used to close gaps in between teeth horizontal elastics or intramaxillary elastics or intra-arch elastics The force recommended: non extraction cases: 1 ½ TO 2 ½ oz extraction cases: 2 to 4 oz CL II Elastics / intermaxillary elastics / interarch elastics Upper canine hook to either the lower 1st molar hook or 2nd molar hook. The force recommended: non extraction cases: 1 ½ TO 2 ½ oz extraction cases: 2 to 4 oz Class III elastics are intermaxillary elastics placed posteriorly on the maxillary arch and anteriorly on mandibular arch. 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. Use: Extrusion of upper posterior and anterior teeth Lingual tipping of the lower anteriors Recommended force: 1/4 in with 3 ½ oz  In deep bite cases it is useful to: protract the maxillary arch procline maxillary incisors: bond them upside down to advance Point A use inclined 45° bite plate with Class III elastics use utility M loop to advance upper arch use brackets with buccal crown torque on lower incisors to resist the extrusion and lingual tipping elastic force ( to avoid gingiva dehyscence ).

1. INTRAORAL ELASTICS
ACHIEVED BY: Dr.Maen Dawodi

2. CLASS 1 ELASTICS
• Upper 1st or 2nd molar hook to the upper canine hook.
• Used to close gaps in between teeth
• horizontal elastics or intramaxillary elastics or intra-
arch elastics
• The force recommended:
– non extraction cases: 1 ½ TO 2 ½ oz
– extraction cases: 2 to 4 oz

3. CLASS 2 ELASTICS
• CL II Elastics / intermaxillary elastics / interarch
elastics
• Upper canine hook to either the lower 1st molar
hook or 2nd molar hook.
• The force recommended:
– non extraction cases: 1 ½ TO 2 ½ oz
– extraction cases: 2 to 4 oz

4. Clinical case of one Class II elastic placed on the upper
sectional to settle the canine relationship.
Other Class II elastic placed on the contraction utility archwire to
help the incisor retraction and torque

5. Clinical example of a Class
II canine relationship
associated with a Class I
molar relationship before
treatment
After treatment of a
Class II elastic placed on
a sectional maxillary arch

6. Class III elastics are intermaxillary
elastics placed posteriorly on the
maxillary arch and anteriorly on
mandibular arch.
Class III Elastics Forces

7. • 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.
• Use:
– Extrusion of upper posterior and anterior teeth
– Lingual tipping of the lower anteriors
• Recommended force: 1/4 in with 3 ½ oz

11. Clinical applications of Class III elastics
• In deep bite cases it is useful to:
– protract the maxillary arch
– procline maxillary incisors: bond them upside
down to advance Point A
– use inclined 45° bite plate with Class III elastics
– use utility M loop to advance upper arch
– use brackets with buccal crown torque on lower
incisors to resist the extrusion and lingual tipping
elastic force ( to avoid gingiva dehyscence ).

12. • In borderline or open bite cases it is useful to:
– segment the maxillary archwire behind the first
upper premolar
– keep the posterior wedges
– avoid increasing the vertical sense
– use short closing anterior Class III elastics
– check and watch T. M. J.

13. The deeper the overbite, the better the
prognosis in Class III malocclusions.

14. Clinical problems with Class III elastics
Many clinical problems may be observed even with careful
clinical management such as:
• insufficient wearing
• excessive wearing
• parodontal problems:
lower incisors dehyscence
• biomechanics problems:
lingual tipping or excessive extrusion
of lower incisors.

15. Particular Intermaxillary Elastic
Many intermaxillary elastics may be used for a
specific extrusion component associated in
conjunction with others such as contraction, in a
horizontal or vertical way.

16. THE BOX ELASTIC
¼” 6 oz or 3/16” 6 oz
• This elastic has a box shape
adding a contraction and
extrusion force movement.
• It is well indicated for closing
spaces and extruding a segment
of the dental arch.
• So it can be placed:
- posteriorly
- anteriorly

18. U SHAPE ELASTIC
• A contraction and extrusion
effect on only one arch.
• Be used with a segmented
arch to the antagonist arch
and can be used in U shape
or upside down.

19. V SHAPE ELASTIC
3 ½ oz
• This elastic has a vertical
component of extrusion
without a light contraction.
• It can be worn to bring a
tooth on the occlusal plane
in a V shape or upside down
according to the clinical
need.

20. M OR W SHAPE ELASTICS
¾ in, 2 ounce
• These elastics are used
for extruding a group of
teeth in order to
squeeze the bite in an
effective closing way.
• Heavy elastic up to 300
g. may be used

22. ACCORDION ELASTICS
Same purpose as the M or W ones, but they add
a contraction component
--for closing spaces when extruding a
group of teeth

23. DELTA ELASTIC
1/8” 3 ½ oz
A short triangle using a vertical component of
extrusion for a single ectopic tooth, most of
the time an upper canine

24. Delta Class II Elastics
• Oriented from the lower molar, over the upper cuspid and
vertically, to the lower cuspid brackets
• Class II molar correction and extrusion of upper and lower
incisors
• Tendency for lower molar extrusion

25. Delta Class III Elastics
• Oriented from the upper molar under the wing of lower
cuspid bracket and vertically, upper cuspid bracket.
• Class III molar correction and extrusion of upper and lower
incisors
• Tendency for upper molar extrusion

26. Posterior Delta Elastics
• Oriented around the brackets of the posterior teeth to seat
the buccal occlusion
• Selectively extrude one or more teeth
• Class II or Class III elastics

27. Triangular Elastics
1/8” 3 ½ oz
• Maxillary canine bracket to mandibular
caninepremolar area (plus other possible
configurations)

28. Anterior triangle elastic
• These elastics usually run
from the upper canine hook
to the bottom canine and
bottom 1st premolar hooks
forming the shape of a
triangle.
• This helps in open bite
situations where your top
front teeth don’t touch the
bottom front teeth.

29. CLASS II TRIANGULAR ELASTIC
• Triangular shape with a Class II orientation.
• Indication:
• Vertical component of extrusion of deep bite Class
II clinical cases

30. CLASS III TRIANGULAR ELASTIC
• Triangular shape used for its vertical
component of extrusion of the posterior part
of the maxillary arch as Class III sagittal
correction of occlusion

31. CROSS BITE ELASTICS
¾ inch; 6 oz
Buccal surface of one molar to lingual surface of opposing
molar(all molar bands have lingual hooks attached)
To correct posterior crossbites
Early and/or late in treatment
Time: 24 hours per day

32. They must be differentiated in:
A - homolateral cross bite
B - controlateral cross bite

33. homolateral cross bite
The elastic is usually used
to jump the bite of a tooth
or a group of teeth.
It is placed opposing teeth,
for instance a palatal cleat
lug of an upper molar in
lingual cross bite degree
two, to the buccal hook of
the lower molar of the
same side (or contrary ).

34. CONTROLATERAL CROSS BITE ELASTIC
The controlateral cross bite
elastic is an intermaxillary
elastic placed on opposite
sides of dental arches
-- for example from a
left upper molar buccally to
a right lower molar, or vice
versa.

35. SQUEEZE ELASTICS
Had advocated heavy elastics forces ranging
from 800 to 1500 g. to close the bite for open
bite surgery cases.
Worn 24 hours a day, 3x in 2 weeks

36. Trapezoid elastics, class 1
3/4 inch; 6 oz
Maxillary canine and premolar brackets to
mandibular canine, first premolar, and second
premolar brackets (plus other configurations)
To help level the mandibular arch and improve cusp-
fossa interdigitation in Class 1malocclusion
Time: 24 hours per day

37. Midline elastics
¼ inch, 6 oz
• Maxillary lateral incisor ball
hook over central incisor then
diagonally to opposite
mandibular lateral incisor ball
hook
• To correct midline discrepancies
• Time: 24 hours per day, except
when eating
• Midline elastics are usually
worn with class 2 or class 3
elastics.

38. Wearing all three elastics
simultaneously (midline,
class 2, and class 3) can
cause a cant of the
occlusal plane.

39. Sequence of Elastics
• Crossbite elastics
• Class 3 elastics after bonding of the mandibular arch to
prevent incisor flaring
Early in treatment

40. Midtreatment
• Box elastics to help close
open bites and/or level the
mandibular arches
• Class 2 elastics for minimum
mandibular anchoragein
extraction cases
• Class 3 elastics to maximize
mandibular anchorage in
extraction cases
Finishing archwires
• Class 2 elastics to achieve
occlusion in centric relation
• Midline elastics with class 2 or
class 3 elastics
• Box elastics to improve
occlusion
• Finishing elastics

41. CLASSIFICATION OF ELASTICS

42. I. According to Material
• Latex Elastics:
– These are made up of natural rubber materials, obtained
from plants
– The chemical structure of natural rubber is 1, 4
polyisoprene.
• Synthetic elastics:
– These are polyurethane rubber contains urethane linkage.
This is synthesized by extending a polyester or a polyether
glycol or polyhydrocarbon diol with a diisocynate.
– These are mainly used for elastic ligatures.

43. II. ACCORDING TO THE AVAILABILITY
• Different makers have different sizes and
force, and the colour coding and the name is
also different.
• Example:
– DENTARUM
– T.P. elastics
– B. M UNITEX
– AMERICAN ORTHODONTICS
– ORMCO

44. III. ACCORDING TO THE USES
1) Intra oral
2) Extra oral
IV. ACCORDING TO THE FORCE

45. SIZE(mm)
FORCE(oz;grams)
Code

46. Size (mm)
Force ( oz;grams)
Code

49. Ormco

50. 3M

51. RMO –
PROS APAC

55. REFERENCE:
• Optimization of Orthodontic Elastics by Michel Langlade,DCD,DSO,DUO
• The 20th Principles of the Alexander Discipline by R.G. Wick
Alexander,DDS,MSD
• https://www.rmortho.com/products/category/elastics/
• https://www.3m.com/3M/en_US/orthodontics-us/products/
• https://ormco.com/pdf-downloads/products/catalog/Ormco-
Catalog_2013_121013.pdf
• http://www.archwired.com/Elastics1.htm
• https://www.slideshare.net/ricobenavides/elastics-in-orthodontics-
29392723