Fixed expansion orthodontic appliances / /certified fixed orthodontic courses by Indian dental academy

FIXED EXPANSION
ORTHODONTIC
APPLIANCES

www.indiandentalacademy.com

INDIAN DENTAL ACADEMY
Leader in continuing dental education


Introduction
Expansion in arch has been one of the oldest
means of creating space in the dental arches.
• It is also one of the conservative method of
gaining space.
• It can also be used to correct the intermaxillary
and dental arch relationships primarily in
transverse direction.
• It enables correction of crossbites early in
treatment.

History
• Narrow maxilla was recognized for thousand
years and Hippocrates has also refered to it.
• In 1860 Emerson C.Angell placed a screw
between maxillary premolar of a girl aged 14 yrs
and wider her arch in two weeks.
• In 1877 Walter coffin demonstrated the
expansion of the maxillary arch using spring
which caused separation of the mid palatal
suture in children.





Pfaff, in 1929 described improved nasal
function after maxillary expansion.
Haas, in 1960 reported increased nasal
width,gain in arch and lowering of
mandible with bite opening.


CLASSIFICATION
1.Fixed or Removable
2.Fixed
• Rapid maxillary expansion
• Slow maxillary expansion


Rapid maxillary expansion
appliances


Banded appliances

- Derischweiler type
- Haas type
- Beiderman type
- Issacson type
- Arnold type


Bonded RME appliance



Full coverage bonded RME appliance



Removable RME appliance



Hilger’s palatal expander

Rapid maxillary appliances
Indications
•Marked narrowing of the arches
•Unilateral or bilateral cross bite
•Mandibular prognathism with reduced anterior development
of the maxillary base
•Steep palate with septal deviation and mouth breathing due
to enlarged adenoids
•Cleft lip and palate
•Mild arch length to tooth material deficiency.(1mm of
expansion in post = 0.7 mm increase in arch perimeter)

Contraindications


No true contraindications



Anterior open bite cases



High FMA, convex profile cases



Skeletal asymmetry of maxilla and mandible with severe
anteroposterior discrepancy.



Older age group due to ossification of sutures



Patients on dilantin therapy


Appliance design criteria
Rigidity
Tooth utilization maximum
 Economy
 Hygiene





Banded appliances
Derischweiler type:
•Tags are soldered to the palatal
aspects of bands to provide
attachments for the acrylic.
•Acrylic also extends to the
palatal of all non banded
teeth except incisors


Haas type:
• A length of the wire is soldered
along the palatal aspects
of the bands.
• Free ends turned back
and embedded in acrylic.
• A screw is incorporated.
• Banding difficult on
malposed teeth.
• Banding and cementation
difficult on deciduous teeth.
Indication
• In late mixed and early
permanent dentitions.

Beiderman type







This design also called
hygienic palatal expander.
Requires a special screw.
These have extensions in
heavy gauge wire which are
soldered to the palatal
aspects of bands.
Acrylic free palate, so no
food entrapment, mucosal
irritation and no ulceration.

Indication

Deciduous and early mixed
dentition.

Issacson type
•This appliance has a special
spring loaded screw
called a minne expander
•It is soldered directly
to the bands
•No acrylic is used
•Easy to fabricate


Arnold appliance






Coil spring expander is
attached by means of vertical
half tubes on the molar bands.
Tubes cosist of coil springs
It expands the arch by lingual
pressures,using coil springs for
power


Bonded appliance








Raymond Howe in 1982 developed this appliance
Clears the palate from acrylic
No banding needed- can be used on malposed teeth where
parallel path of insertion is not possible
Less error prone as bands don’t have to be placed in
impression
Easy to make on deciduous teeth.

Wire framework

Completed appliance
On model

Acrylic-lined bondable
RME appliance


Full coverage bonded RME appliance








Developed by John Spolyar in 1984
Solely for tooth borne anchorage
Spider type expansion screw is placed as anteriorly as
possible
Acrylic free palate
No bands present
Difficult to remove

Appliance showing
Anatomy surface

Extent of occlusal
coverage

Appliance on
Study model

Removable RPE appliance










Developed by Vel Ivanovski in 1985
Used for correction of crossbite and expansion of both
maxilla and mandible
No bands, clasps and easy to fabricate
2 mm thick acrylic sheet are moulded on the models with
screw stabilized on the models using biostar
In a single appliance extension are given to the lingual of
mandibular teeth for simultaneous expansion
Separate upper and lower appliances can also be made


Hilgers palatal expander –
PEND-EX Appliance
•Consist of two molar bands with
soldered horizontal helices and
an acrylic plate
•With embedded jackscrew
•Anterior extension of the wire serve as
the bonded occlusal rest
•Helices serve to rotate and distalize
the upper molar
•Jack screw produces orthopedic
midpalatal disjunction

Activation






Use head gear plier to twist the molar bands distally to
incorporate twice the the amount of rotation needed
Place the lingual bend in the vertical portion of the wire that
extends out of the acrylic.
Hold the helical with the head gear plier and bend the
appliance towards palate to place a minor tip back force on
the molars

Advantages






The appliance is able to make changes in arch width and
form
Distal rotation of upper molars
Creates room for canine eruption
Anchors the molars during upper retraction

Regime of screw rotation
Upto age of 15 years : the turn 180 degree is given as
90 degree in the morning and 90 degree in the
evening.
15-20 years : overall rotation of 180 is possible by
splitting the rotation into 4 turns of 45 degree each with
approx equal time lapse between them.
Age over 20 years : 45 degree turn in the morning and
45 in the night initially
Over 25 years: surgical separation may be required.


Zimring and Isaacson in 1965 :




Young or growing patients: two turns each day
for the first 4-5 days and one turn each day for
remainder of rme treatment.
Adult patients: two turns each day for the first
two days and one turn each day for the next 5-7
days and one turn each other day for the
remainder of the RPE treatment.


Effects of RPE






The separation of midpalatal suture is triangular in all three
planes.
The fulcrum of separation lies at varying distance from MPS
depending on age.
There is generally downward and forward movement of
maxilla due to zygomatic buttressing.

Sagittal









The mandible also rotates downward and backward exaggerating
retrognathia.
The alveolar bone bends laterally and the palatine bones inferiorly
increasing nasal cavity.
Splaying of hamular processes of the sphenoid bone is seen.
As the maxilla moves forward and downward due to loosening of the
circummaxillary sutures, maxillary protraction may be applied with
face mask or reverse headgear.



Arch perimeter increase is 0.7 times the intermolar width increase.



Palatal depth is increased due to overeruption of posterior teeth.



Mandibular arch length expansion is also seen in RPE: upto 1.1mm
increase in intercanine width and 2.5mm in intermolar width.

Clinical management of RPE patient


Pain is not usually present in juveniles, adults may complain.



Pain is usually at the time of activation.



Midline diastema is most important proof of separation.



Petechie may be present on the palatal mucosa which
resolves in a week or two.



Occlusal interference are seen.



Patient report inability to masticate from back teeth.



Overexpansion is advised till lingual cusps of upper molars
occlude with lingual inclines of lower buccal cusps.

Slow palatal expansion
Fixed Appliances used





W arch
Quad helix
Ni-Ti arch wires
3D Wilson appliance


W- arch
•A fixed type modification of coffin spring
•First used by ricketts in cleft palate cases
•Prefered in deciduous and mixed
dentition where mild to moderate
expansion is required


Quad helix
Introduced by dr. Robert Ricketts in 1975

Indications:
•All cross bites needing upper arch expansion
•Crowding cases needing mild expansion
•Class II needing molar distal rotation
•Class III with constricted maxillary arch
•Tongue thrusting cases
•Cleft lip and cleft palate cases

Activation

A six week interval is observed before
further activation
Extra oral:
 1mm each side in molar region and 1.5mm anteriorly
 Ricketts prescribes 500 gm of force to separate mps
Intraoral:
 Triple beak plier is used
 Anterior bridge is bend by keeping single beak
anteriorly for intermolar expansion
 2nd and 3rd bend on palatal bridges for lateral arms.



Activation


Can be opened anteriorly at the curve as well as at the posterior
apices



Opened 3-4 mm wider that passive width



Expansion done at the rate of 2 mm per month



Unequal arm length can be kept in true unilateral crossbite cases



Over treatment is done



Can be kept as a retainer for 3-4 months


Ni Ti palatal expanders














Introduced by wendell arndt in
1993
A fixed – removable appliance
Depends on shape memory
and super elasticity of NiTi
Transition temperature 94°F
Continuous force levels
between 230gms to 300 gms.
Available in 8 intermolar
widths; 26-47 mm
26-32mm width appliances are
of softer wires for younger
patients
Freeze gel packs can be used
to make appliance flexible for
insertion

Thank You
Leader in continuing dental education


Fixed expansion orthodontic appliances / /certified fixed orthodontic courses by Indian dental academy

Recommandé

Recommandé

Contenu connexe

Tendances

Tendances (20)

En vedette

En vedette (6)

Similaire à Fixed expansion orthodontic appliances / /certified fixed orthodontic courses by Indian dental academy

Similaire à Fixed expansion orthodontic appliances / /certified fixed orthodontic courses by Indian dental academy (20)

Plus de Indian dental academy

Plus de Indian dental academy (20)

Dernier

Dernier (20)

Fixed expansion orthodontic appliances / /certified fixed orthodontic courses by Indian dental academy