Clasps orthodontic /certified fixed orthodontic courses by Indian dental academy

Clasps

www.indiandentalacademy.com

INDIAN DENTAL ACADEMY
Leader in continuing dental education




The name clasp is derived from
a French word “UYPTAN” which
means to embrace. Clasps are
the retentive components of the
orthodontic appliances.


 RETENTION

:- is the
means whereby the
displacement of an
appliance is resisted.


Why retention is needed ?




IF poor retention - difficulty to
wear-poor pt co-operation.
If the appliance is not seated
properly-the active components
may not function properly due to
continual movement of
appliance, breakage of springs
are liable.





In children the undercut may lie
just below the gingival margin,
and it is necessary to construct
the clasp so that it displaces the
gingival margin slightly.
It is important that the clasp
does not extend too far into an
undercut area.


IDEAL REQUIREMENTS
Unobtrusive.
 Not impinge.
 Close contact to the tooth.
 Usable in both deciduous and
permanent dentition.
 Adequate retention.



No active force on the anchor
tooth.
 Rigid
 Easy to fabricate and also
replace if needed.
 Not interfere in the growth of
jaws and eruption of teeth.
 Clasps should be at the center
of the buccal segment to ensure
stability of the appliance.



CLASSIFICATION
A. Hand Made
Machine Made.
B. Single tag arm
Double tag arm

MODE OF ACTION




Clasp engage onto the
undercuts (constricted areas on
the teeth.)
Two types of undercuts.
 Buccal

/ Lingual Cervical
undercuts.
 Mesial / Distal Proximal undercuts.


CIRCUMFERENTIAL
CLASP








Circumferential clasp / C-Clasp /
3/4th Clasp.
To use the bucco-cervical
undercut.
2nd molar and canines.
Single retention arm.
1mm wire used in molars.


Advantages of C clasp





Good retention.
Easy to fabricate.
Single occlusal crossover wire.
Easy to replace.


Disadvantages of C clasp







Not on semi-erupted tooth.
Decalcification of cervical
margin.
Gingival irritation.
Plaque accumulation enhanced.
Easily distort.


JACKSONS
CLASP









V.H. Jackson 1906
Jacksons Clasp / Full Clasp / U
Clasp.
Both bucco-cervical and
proximal undercuts.
0.7mm to 1mm.


Advantages



Simple design
Adequate retention.


Disadvantage





Not useful in partially erupted
teeth.
Difficult to adjust.
Not on unfavorably inclined
tooth.


SOUTHEND
CLASP






Most common for anterior
anchorage.
Single arrowhead between CI
with wire following the gingival
margin.


Advantages of southend clasp




Unobtrusive.
Good retention.
Even be used if Incisors are
proclined.


TRIANGULAR
CLASP









Also called as MODIFIED
ZIMMERMANS CLASP.
Excellent retention by the single
arrowhead in the interproximal
area.
Open end towards the occlusal.
Can engage elastics.
0.7mm wire

Advantages of triangular clasp





Easy to fabricate.
Excellent retention.
Pre fabricated available.
Elastics can be engaged.


Disadvantages of triangular clasp




Not useful if adjacent tooth is
absent.
Used as secondary or additional
retention.


BALL END
CLASP






Action and location similar to
triangular clasp.
Prefabricated available. Can be
made by adding solder to end of
a wire.


Advantages of BALL END CLASP





Easy to fabricate.
Single occlusal interference.
Less gingival irritation.
Easy to replace.


Disadvantages of BALL END
CLASP






Short arm makes adjustment
difficult.
Can not be used for primary
retention.
Cannot be used in absence of
adjacent tooth.


SCHWARZ
CLASP







Also called as ARROWHEAD
CLASP.
A.M. Schwarz 1935.
Mesial and distal undercuts of
the teeth.


Advantages of SCHWARZ
CLASP






Reliable retention.
Does not interfere in posterior
occlusion.
More wire hence more flexible.
More easy to adjust.
Enhances eruption.


Disadvantages of SCHWARZ
CLASP






Difficult to fabricate.
Needs special plier.
Irritates soft tissue.
Tends to separate teeth.
Is bulky hence less patient
compliance.


CROZAT CLASP







Crozat in 1920
Along with the u clasp a stright
wire is soldered on the base
(Cresent).
Strong retention is possible


ADAMS
CLASP









Adams clasp / modified arrowhead
clasp / liverpool clasp / universal
clasp.
C. PHILIPS ADAMS in May 1950.
Most widely used clasp.
Distobuccal and mesiobuccal
undercuts.
Does not separate teeth like a
arrowhead clasp.
0.7mm posteriors
0.6mm anteriors.

FABRICATION


parts

BRIDGE
o 2 ARROWHEADS
o 2 TAG ARMS
o


BRIDGE




Is 2/3rd the mesio dital width of the tooth, or
slightly less then the distance between
mesiobuccal and distobuccal undercuts, or
length should be equal to the intercuspal
distance.
Is 1-2mm away from the buccal surface of
the tooth.



Is at 45o to the buccal surface of the tooth.



Should be straight.


Arrowheads








They should lie in the disto- and
mesio buccal undercuts.
Shaped according to the curve of the
gum margins in the direction of the
interdental papilla.
Long enough to keep the bridge at a
proper distance.
Should not touch the adjacent teeth


Tag arms






Closely fitted to the contact points,
down to the interdental embrasure.
Space between the tag arms and
palate for flow of acrylic.
No sharp bends.


Advantages of ADAMS CLASP








Small neat and unobtrusive.
Any tooth.
Both deciduous and permanent
dentition.
Even on semi erupted tooth.
No specialized pliers required.
Can be modified as needed.
No. of variations are available.


Disadvantages of ADAMS CLASP








Unwanted palatal tipping if gets
activated.
May lead to elongation of tooth
if is fitting tightly.
Can be repaired only if fractured
through the arrowheads.
Cannot be given on proclined
anteriors.

ADJUSTMENTS



NEAR THE ARROWHEADS
ON THE OCCLUSAL CROSS OVER


MODIFICATIONS


Anterior adams



0.6mm
Also called double clasp.


With distal extension/ traction hook



To engage elastics
Not given if sulcus is shallow.


With eyelet


With a soldered hook


With a soldered tube


With a single arrowhead


With accessory arrowhead


Smart clasp


Delta clasp


Leader in continuing dental education


Clasps orthodontic /certified fixed orthodontic courses by Indian dental academy

Recommended

Recommended

More Related Content

Viewers also liked

Viewers also liked (20)

More from Indian dental academy

More from Indian dental academy (20)

Recently uploaded

Recently uploaded (20)

Clasps orthodontic /certified fixed orthodontic courses by Indian dental academy