Expansion in orthodontics (2)

EXPANSION IN
ORTHODONTICS
www.indiandentalacademy.com

INTRODUCTION
The prime objective of expansion is to
coordinate the maxillary and
mandibular bases

Hippocrates
“Among those individuals where heads are
long shaped, some have thick necks, strong
members and bones, others have strongly
arched palates, their teeth are disposed
irregularly crowding one over the other
and they are suffering with headaches and
ottorrhea”.
Historical background

Emerson Colon Angell 1860,
San Francisco

A.Coleman 1877 described coffin
spring
Field: coffin can cause separation of
MPS in very young children
Farrar: “separation of superior maxilla
at the symphysis”
Supported by Clark L Goddard,
E.S.Talbot and A.E.Matteson.1893

Anatomical considerations
MAXILLA

SUTURESSUTURES

 Marked narrowing of the arches
 Unilateral or bilateral cross bite
 Mand 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)
INDICATIONS

CONTRAINDICATIONS
 Uncooperative patients
 Pts with anterior open bites, and steep
mandibular plane angles

CLASSIFICATION OF APPLIANCES
 According to the rate of expansion
– Slow
eg W arch, Quad helix, Coffin spring
– Rapid
eg Hyrax, Isaacson
– Surgically assisted

 According to appliance attachment
– Removable
eg Active plate and Functional appliances
– Fixed:
• Tooth borne
eg, Biedeiman appliance, Minn expander
• Tooth/Tissue borne
eg Derichsweiler type, Haas type.

 According to modality employed
– Orthodontic expansion
– Passive expansion
– Orthopedic expansion

REGULATION OF EXPANSION
 Rate of expansion
 Form of the appliance
 Age of the patient

Rapid maxillary expansion
 Orthopedic expansion
 Force levels of upto 10-20lbs per day
 Active phase 2-4 weeks

REQUIREMENTS OF AN RME
APPLIANCE
 Rigidity
 Tooth utilization
 Expansion( dilating unit and action)
 Economy of time and material
 Hygiene

Banded type of appliances
 Hass type
 Derichsweiler type
 Isaacson type
 Biedeimann type

Bonded type Mundro et al 1977

Instructions on how to expand
Zeibe in 1930 : 180 degree rotations per day
 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

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 eac other day for the
remainder of the rme treatment.

HAZARDS OF RME
 Oral hygiene
 Length of fixation
 Dislodgement and breakage
 Tissue damage
 Infection
 Failure of suture to open

Reaction to expansion
IN BONE
SUTURES
DENTAL CHANGES

Relapse and Retention
 The object of retention is to hold the
expansion while all other forces generated
by the expansion have decayed away.
 It is essential for the fixed appliance to act
as the retention appl in the first three
months.
 Wertz observed that some relapse is seen
in the forward and downward movement of
the max.

SLOW MAXILLARY EXPANSION
Story and Ekstrom: Slow expansion allows
physiologic adjustments and reconstitution of
sutural elements over a period of about 30 days.
 2-4 lbs of force, a little higher for older
patients.
 1 mm expansion per week.
S. E. has also been associated with more
physiologic stability and less potential for relapse
than with R. M.E.

Appliances used for S. M. E.
Jackscrews

TYPES OF SCREW
Broad classification:
 Encased type
 Skeleton type
 Special screw
 Eccentric screws

Coffin spring

 W - Arch

Quad helix

OTHER METHODS OF EXPANSION
 NITI AND OTHER ARCH WIRES
 MAGNETS
 TRANSPALATAL ARCH
 SURGICALLY ASSISTED EXPANSION
 ULTRA RAPID EXPANSION

Ultra-rapid maxillary expansion
of Chatellier
 The procedure involves local anesthesia
and results are obtained within 1 to 3
days
 As a rule, the ultra-rapid method is
performed over a period of 3
appointments

Niti expander
Wendell Arndt

Functional appliances

Magnets
 M. ALI DARENDELILER
 Two repelling samarium cobalt magnets
 Pins and tubes were placed to guide the
separation of the palate.
 The midpalatal magnets (each 10mm×5mm×5mm)
produced 500g of force, which declined to 250g
during the three weeks between activations

Transpalatal Arches
 An important auxiliary used in fixed appliance
therapy with several indications one of which
is expansion or constriction but of small
measures of upto 1-2 mm.

Surgically assisted maxillary
expansion
The resistance in the maxilla separation can
be due to either of the following reasons:
mid palatal synostosis
mid palatal interlocking
circum maxillary rigidity

The tech has been described in 3 stages:
Stage 1 A and B
Stage 2 A and B
Stage 3 A and B

Stage 1

Stage 2 (over the age of 30)

Stage 3 (over the age of 40)

Expansion of cleft palate
cases
 Excessive anterior collapse coupled to little or no
posterior collapse
 More fan wise expansion needed to restrict
posterior Expansion. Screws of longer thread of
upto 18mm expansion
 More difficult to retain due to clinical crowns not
developed properly
 Unilateral expansion both cap splints and bands
can be used
 Formation of fistula could be a complication

Expansion of the mandibular arch
 Stable expansion is difficult to attain in the
lower arch
 Present studies state that expanding the upper
arch allows for spontaneous expansion of the
lower arch.

CONCLUSION
Expansion of the arches has seen its ups and downs in the
past. More and more documentation of the effects and
stability of this procedure has thrown a new light on its
clinical application.
Whether it is slow, rapid or ultra rapid expansion, proper
diagnosis and case assessment is very essential to ensure
consistent results. As more and more cases are being
treated without extractions due to profile considerations,
expansion of the arches forms a valuable adjunct to treat
a wide variety of clinical presentations.

MOLAR DISTALIZATION

 Class II Malocclusion
 Non-Extraction treatment
 Non-Compliance therapies
 Treatment - Molar Distalization
 Space regaining procedure
-Mesial migration of first permanent molars

Indications for Molar
distalization
1. In a growing child
- to relieve mild crowding
- causes permanent increase in arch
length of about 2mm on each side.
2. Late mixed dentition
- When lower E space –utilized for relief of
anterior crowding,
- Upper molars distalized to get a class I
relation

distalization
3. Non-growing patient
- To regain lost arch length
- Blocking out of canines
4. Upper second molar extraction
- Lower arch normal

Indications for Molar distalization
 Class I malocclusion- with highly placed canine/impacted
canine
 Lack of space for eruption of premolars due to mesial migration of
permanent first molars

 End on molar relationship
with mild to moderate space
requirement
 Cases with less than a full
cusp class II molar
relationship
distalization

distalization
 Good soft tissue profile
 Borderline cases
 Mild to moderate space discrepancy with
missing 3rd
molars/2nd
molars not yet
erupted

distalization
 Axial inclination :
Mesially angulated upper
molars
 Normal or Hypodivergant
growth pattern
 Late mixed dentition with
mild crowding of anteriors

Case selection
1. Normal or near normal mandibular arch
2. Late mixed dentition-ideal
- Early permanent dentition-growth still left in maxillary
tuberosity area.- 16-17 yrs-males
14-15 yrs-females
3. Molars placed normally- buccolingually
4. 3rd
molars-absent –stacking of upper molars – unsuitable
5. Profile considerations- well developed nose & chin
6. High MPA- contraindicated-wedging effect
7. Space discrepancy- not very severe

Classification
1. Location of appliance
 Extra-oral
 Intra-oral
2. Position of appliance in mouth
 Buccal
 Palatal
3. Type of tooth movement
 Bodily movement
 Tipping movement

Classification
4. Compliance needed from patient
 Maximum compliance
 Minimum or No compliance
5. Type of appliance
 Removable
 Fixed
6. Arches involved
Intra-arch
Inter-arch

Various appliances used for
Molar Distalization :
Headgears
Wilson Bimetric arch design
Crozat appliance
Crickett appliance
Modified Nance Lingual appliance
Schmuth and muller double plates
Molar distalization with magnets

Various appliances used for
Molar Distalization
 Use of Super elastic NiTi
 Jones Jig
 The Pendulum appliance
 Claspring
 Removable molar distalization splint
 Fixed piston appliance
 The K-loop appliance
 The distal jet
 Using Implants
 Fixed functional appliances

Distalization using Headgears
 Very efficient
 Reciprocal forces are not transmitted to other teeth
 Molar movements depends on direction of force in relation to
the C Res of the molar & magnitude of force

Biomechanics of Headgears:
 C Res
 Moments

Straight pull headgear
 Class II Malocclusion with
no vertical problems
 Prevent anterior migration
of maxillary teeth, translate
them posteriorly
 Buccal force to molar -
Expansion of inner bow

Cervical Headgear
 Short face Class II
maxillary protrusive
cases with low MPA
& Deepbites
 Extrusive &
distalizing effect

High pull Headgear
 Produces intrusive &
Posterior direction of pull
 Long face class II patients
with high MPA
 Force through c res –
Intrusion & distal
movement of molar
 6-8 months – class II-
classI
Adv-effective, no reciprocal forces
Disadv- Patient compliance

Bimetric system for Molar
Distalization
 Dr.Wilson-Tandem yoke
with bimetric arches for
molar distalization
 Tandem yoke-.045” round
tube – slides on .040” end
section of the bimetric loop.
 .018 retractor
 .045” coil spring for
distalizing
 Intermaxillary traction

 Coil spring- between molar
tube & the yoke
 Elastics- 12 hours a day
 Headgear – at night
 The Omega adjustable
stop –to modify & control
arch length
 Crimpable .040”tube
 .061 Omega loop
 Coil springs &
intermaxillary hooks.

Bimetric arch modified by Dr.
Jayade
 Class II correction- Distalization + expands canine-
premolar area- unlocks the occlusion
 A mild-moderate class II div 2 with normal mandibular
arch-easily corrected

Bimetric arch modified by Dr.
Jayade
Archwire design:
 .016”premium wire
 Premolars bonded if
expansion is required
 Teardrop shaped loop
 Bite opening bend
 Mild toe-in
 2mm activation

Elastic load reduction principle:
 Class II elastics – used sequentially
T.P Green – 1st
week
Pink - 2nd
week
Yellow – next 2-3 weeks
 Initial heavy force- to resist forward
pushing force of new wire- force
transferred distally
 Later Molar uprights-mesially directed
archwire force decreases- support with
light forces.
 Extrusive component of class II- kept to a
minimum
Borderline cases –Non extraction

Modified Nance and Lingual
appliances for unilateral tooth
movement Ghafari JCO 1985
Nance holding arch :
 Palatal arch attached to first molar
bands , embedded in an acrylic
"button"
 space maintainer in the maxillary
arch,
 support maxillary posterior
anchorage during tooth movement
Modified Nance holding arch and
modified lingual arch:
 Anchorage for unilateral
distalization of posterior teeth
 No patient compliance required

Modified Nance and Lingual
appliances for unilateral tooth
movement
Modified Nance holding arch
 12 yrs/M
 Skeletal & Dental class I
 Right side- distoocclusion
 2nd
premolar- 3.5 mm space
 R – 1st
PM & molars banded
 Segmental .019 x .025 NiTi
 Open coil spring
 4 months
 No labial movement of incisors

K-Loop Molar Distalizing
Appliance
Valrun Kalra –
JCO 1995
 K-loop – forces - .017 x .025 TMA
 Nance button – anchorage
 8mm long , 1.5 mm wide
 Legs- 20 degree bend
 Inserted into molar and first
premolar tube, marked
 Stops bent 1mm distal , 1mm
mesial
 Stops- 1.5mm long

K-Loop Molar Distalizing
Appliance
Valrun Kalra –
JCO 1995
 Reactivated 2mm 6-8
weeks later
 Molars move by 4mm,
premolars by 1mm
 Anchorage can be
reinforced by headgear

K- loop Appliance

Removable molar distalization splint
Dr. Karrodi Ritto JCO 1995
 Splint – 1.5mm Biocryl-Biostar machine
 More esthetic & comfortable
 Bilateral- 1st premolar- 1st
premolar
 Unilateral – Premolar – Opposite Molar
 Two internal clasps – retention
 NiTi open coil spring- 220 gm force
 1.5mm-2mm/month

Distalization of Molars with
Repelling Magnets Gianelley etal JCO
1988
 Anchorage – Modified Nance
appliance
 Wire extending from 1st
premolars
 Acrylic button anteriorly
contacting the incisors
 Auxillary wire with a loop at its
end soldered - premolars bands

Distalization of Molars with
Repelling Magnets
 Incisor brackets – passive
sectional wire- maintain incisor
alignment
 Repelling surfaces of magnets
brought into contact by passing
an .014 ligature through the loop,
then tying back a washer anterior
to the magnets
 Force- 200-225 gms , dropped as
space opened
 3mm in 7 weeks
 Anchor loss – 1mm

Japanese NiTi coils used to move
molars distally -Gianelly AJO
1991
 100 gm superelastic coils
 Nance appliance with bite plate
in anterior region
 .016 x .022 wire with stops
abutting distal wings of premolar
and molars
 Coil – between 1st
premolar and
the molars
 .018 “ uprighting spring placed
in vertical slot of
premolars,directing crowns
distally

Japanese NiTi coils used to move
molars distally
 2nd
molars erupted- Class II elastics
 Rectangular wire – 10 degree lingual root torque
 Once distalized, Coils &Nance appliance are removed, insert .
016 x .022 “ wire with stops + High pull headgear to upright
roots of molars

Molar distalization with
Superelastic NiTi wire Gianelly JCO
1992
 100gm Neosentalloy upper
archwire
 3 markings
 Stops crimped, hook added
 Insert wire such that posterior
stop abuts mesial end of molar
tube, anterior stop abuts distal of
premolar
 Anchorage reinforced by class II,
or Nance appliance

NiTi Double Loop system for
simultaneous distalization of first and
second molars Giancotti JCO 1998
 Mandibular molars and 2nd
premolars
banded, other teeth bonded
 Lip bumper- prevent extrusion
 Maxillary molars and bicuspids –
banded, aligned
 80 gm Neosentalloy – maxillary
archwire placed – marked
1. Distal to 1st premolar
2. 5mm distal to 1st
molar tube
 Stops crimped on markings

second molars
 Sectional NiTi archwires –
crimp stops
1. Mesial and distal to 2nd
premolar
2. 5mm distal to 2nd
molar
tube
 Uprighting springs on 1st
bicuspids
 Class II elastics
 Simultaneous, bodily
movement
24yr/f, class II div I
5months- overcorrected

second molars
 Minimal patient co-operation
 Ideal for simultaneous distalization
 Anchorage easily controlled , without need for TPA/Nance
 Due to streching of transeptal fibres, 1st
molars can be
distalized using lighter 80 gm force

Pendulum Appliance for class II non-
compliance therapy
JAMES J. HILGERS,JCO 1992
 Nance button
 .032 TMA springs
 Broad swinging arc
(Pendulum) of force from
midline of palate to upper
molars

Pendulum Appliance
Fabrication :
Pendulum springs consist of
1. Recurved molar insertion
wire
2. Horizontal adjustment loop
3. Closed helix
4. Loop for retention in acrylic
button
 Springs- close to center of
Nance button
 Anterior portion- retention-
occlusally bonded rests
- Band
upper 1st
premolars, solder
retaining wire to the bands

Pendulum Appliance
 Nance button- extend to about 5mm
from teeth
 Anterior retention loops fixed on
model, later soldered to bicuspid
bands
 Acrylic pressed against the palatal
vault
 Pendulum springs inserted

Pendulum Appliance
Pend-X
Jack-screw-One-quarter turn
every 3 days

Pendulum Appliance
Preactivation and placement:
 Springs bent parallel to midline of the
palate
 Molar bands cemented
 Anterior portion of appliance later
cemented
 Pendulum spring brought forward &
engaged in lingual sheath
 As molar distalizes, moves on an arc
towards midline- counteracted – opening
horizontal loop

Pendulum Appliance
 Reactivate if required
 Reavtivated by pushing it distally towards the midline
 Stabilize after correction
 Nance appliance
 Full arch bonding – continous wire with omega loop
 Headgear for few months

Pendulum Appliance
 Unilateral correction

Pendulum Appliance
Conclusion :
 Excellent patient tolerance
 Upto 5mm distalization in 4 months
 Distalization + Expansion
 Patient compliance not needed
 Modified Pendulum Appliance- Scuzzo- 2000 April
Removable arms

Removable pendulum

Open Coil Jig
Jones, White –JCO 1992
Oct
 Richard D. Jones
 American Orthodontics
 Open coil NiTi spring
 Nance appliance

1. Heavy round wire
2. Light wire
3. Fixed Sheath
4. Hook
5. Sliding Sheath
6. Open coil spring
3
1
2
5
6
4
Open Coil Jig

Open Coil Jig
 Advantages…
 Reactivation
 4-5 mm distalization in 3-4 months
 Disadvantages-
-Tipping
- Cannot use with fully banded treatment
- Breakage

Distal jet Appliance
Aldo Carano, Mauro Testa
JCO 1996
 Fixed lingual appliance
Appliance design :
 Wire extending from acrylic
through tube ends in a bayonet
bend-inserted into lingual sheath
 Coil spring
 Clamp
 Anchor wire to 2nd
premolar

Distal jet Applaiance
Aldo Carano, Mauro Testa
JCO 1996
 Reactivation- sliding clamp
closer to first molar
 After distalization –
- clamp-spring assembly-
acrylic,
- premolar arms cut off.

Distal jet Appliance
Advantages :
 Bodily movement
 Easy insertion
 Well tolerated
 Esthetic
 Unilateral, Bilateral
 Permits simultaneous use of full bonded appliances

Modifications of Distal jet
Appliance
Andrew Quick, Angela Harris JCO
2000
Earlier :
 Sliding collar-tightened- small set
screw- Allen wrench
Modification :
 Rear entry of sliding section into the
molar sheath
 Sliding wire- .032 “
 Stop collar soldered to wire
 Activation
 Retention- solid tubing

Fixed piston appliance -
Greenfield
 .036 “ tubing- soldered to
biccuspids
 .030 “ ss wires- first molars
 Nance button
 NiTi coil

Expansion in orthodontics (2)

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