Guide to Molar Distalization Techniques

SEMINAR
ON
MOLAR
DISTALIZATION
www.indiandentalacademy.com

Contents
• Introduction
• History
• Indications and contraindications.
• Diagnostic criteria
• Classification of Appliances.
• Treatment timing.
• Treatment planning and sequence.
• Appliance description.
• Conclusion .
• Bibliography .

INTRODUCTION
In the adult patients there is no clinically
significant growth in the bone structure;
therefore, alternative solutions must be found
to obtain space in which the teeth can be
moved to correct the malocclusion. Treatment
options may differ depending on the amount
of crowding, and whether the crowding has
occurred in the maxilla or mandible.

In the past, orthodontists had two main
options to create the space in the arch.
-Expand the arch and
-Extraction.
However, we the orthodontists of today are
fortunate enough to have more techniques and
appliances in our hands to gain space. i.e. by
distallizing molar.

Current molar distallizing appliances do
not allow effective control and manipulation
of the moment to force ratio. By altering this
ratio, the clinician can achieve bodily
movements, controlled tipping or
uncontrolled tipping as the individual case
dictates. In addition, by varying the
magnitude of moments between the molar
and first premolar, one can produce an
intrusive or extrusive force on the molar.

History
• Kingsley was the first person to try to move
the maxillary teeth backwards in 1892 by means
of headgear.
• Oppenheim advocated the use of occipital
anchorage for moving maxillary teeth distally into
correct relationship without disturbing mandibular
teeth. IN 1944, he treated a case with extra-oral
anchorage for distalizing maxillary molar.

• Kloehn (1951) described the effects of cervical pull
headgear.
• Renfroe (1956) reported that lip bumper primarily
devised to hold hypertonic lower lip caused a distal
movement of lower molars sufficient to change class I to
Class II.
• Gould (1957) was first person to discuss about
unilateral distalization of molars with extra-oral force.
• Graber T-M. (1969) extracted the maxillary II molar
and distalize the first molar to correct class II div.1.
• 1999, A Modified Hilgers Pendulum appliance was
introduced, known as the “M-Pendulum appliance.” To
remove unwanted tipping of maxillary molars by Hilgers

• 2000 a new non-integrated implant-supported device
called the Graz Implant-Supported Pendulum (GISP).
It distalize maxillary 1st & 2nd molars in adults
It consisted of 2 parts: the anchorage plate, which is
fixed to the palatal bone via 4 miniscrews, and the
removable part, which is a pendulum-type appliance
• 2003, Some authors examined the treatment effects
produced by two types i.e the Herbst appliance (acrylic
splint and stainless-steel crown) followed by fixed
appliances, and the pendulum appliance followed by fixed
appliances.
• 2005, Kinzinger modified the standard pendulum
appliance by integrating a distal screw into its base and by
special preactivation of the pendulum springs, called
Pendulum K.

INDICATIONS :
1) Cl-II molar relationship due to maxillary
protrusion
2)Cl-II molar relationship due to impacted/high
labially placed cuspids
3)Cl-II Subdivision cases requiring unilateral
distal molar movement
4)Cl-II molar relationship due to ectopic
eruption of either 1st
/2nd
bicuspid

5) Midline discrepancy cases
6) Regaining the space loss due to mesial drift of
1st molars following premature loss of
deciduous teeth
7) Anchorage loss during active orthodontic Rx.

CONTRAINDICATIONS :
1) An end on or full Cl-II molar relationship
due to mandibular retrognathism
2) Retrognathic profile (Cl-II skeletal with
orthognathic maxilla and retrognathic
mandible).
3) Skeletal and dental openbite
4) Excessive lower anterior facial height
(Dolicofacial form)
5) Constricted maxilla

Diagnostic criteria for distalizing maxillary
molars
The criteria varied widely among the clinician
but some of the most common criterias are:
1) Cl-II or end-to-end molar relationship
2) Good soft tissue drape
3) Good maxillary second molar positions
4) Good expectation for patient cooperation
5) Straight profile and straight divergence

6) Normal skeletal vertical development (facial
proportion should be with in normal limits).
7) Normal transverse development (no cross
bites)
8) Maxillary dental protrusion
9) Low to moderate mandibular plane angle
10) Class I skeletal pattern
11) Mild or moderate crowding

Appliances used for molar distallization:
I. Maxillary
II. Mandibular

I. Maxillary:
A) Extra oral
1. Head gear
( B) Intra oral
1 K loop
2 Pendulum appliance
3 Jones jig
4 Distal jet for upper molar distalization
5 Molar distillization bow
6 Jasper jumper appliance
7 Super elastic NiTi wire

11. Transpalatal arch
12. Upper molar distalization in Begg treatment
13. Denholz appliance
14. Modified Nance appliance for molar distalization
15. Lokar appliance
16. Magnetic distallization appliance
17. ACCO (acrylic cervical occipital appliance)
18. Distallization using microimplants.

19. Removable molar distallization splint
20. Molar distallization system
21. Crozat treatment
22. Fixed piston appliances
23. The lingual distallizer system
24. C-Space regainer for molar distallization

II. Mandible:
1. Lip bumper
2. Franzulum appliance.

Arch length:
A question to be asked is how much arch
length is needed?
a. 2 to 3 mm space/arch length need – TPA
b. 5 mm – All other appliances
c. More than 5 mm – Headgear and Herbst
appliance.

Treatment timing:
Best time to start/initiate molar distalization
would be in late mixed dentition and it may be too late to
start correction after eruption of the second permanent molar .
There appears to be some potential for synergistic
effect as the dentition transitions from primary to
permanent, because,clinically erupting premolars and
canines often appear to follow the molars as they are
moved distally.

Several guidelines have been established for
non-extraction treatment, which limit its
use to cases involving the following:
a) 5mm or less of crowding
b) Several mesially and lingually tipped posterior teeth
(constricted arches)
c) No requirements for stability or esthetics
d) Cooperative patient
e) Growing patient (because they afford more space
and growth)

Treatment planning and sequence:
The treatment approach is divided into two phases.
Objectives of 1st
phase/space gaining phase:
1. To distalize the upper molars bodily so that the
patients will occlude in Super class – I occlusion (i.e.
over corrected).
2.To achieve generalized spacing through dento alveolar
widening and growth.
3.To correct molar inclination, rotation and cross bite.
Objectives of second phase/consolidation phase are:
1. Andrew’s six keys to normal occlusion.
2. Overbite, overjet and all dental malpositions are
corrected. www.indiandentalacademy.com

I. Maxillary
(A)Extra oral
HEAD GEAR

Headgears are mainly used for anchorage. Headgear
can accomplish the following kinds of anchorage
control.
1. Retraction of posterior teeth.
2. Retraction of all teeth in the arch.
3.Restriction of the mesial drift associated with
growth.
4. Restriction of the mesial drift associated with the
premature loss of deciduous teeth.
5. Reduction of the slippage of posterior teeth in Xn
cases (increases anchorage).

6. Increase of the vertical anchorage during Rx
of
deep overbites/open bites.
7. Restrains of the upper jaw when lower jaw is
retracted as in the use of Cl-III elastics.
8. Reduction of the eruption of teeth into inter
maxillary growth space.
9. Protraction of teeth intra-segmentally, inter-
segmentally or even inter maxillary.
Forces applied are constant and force applied is for 14 to 16
hrs/day. Approximately 100 to 200 gm of force/side is appropriate.
Tooth movement should occur at the rate of 1 mm/month, so 3www.indiandentalacademy.com

2 Types of Head Gear forces:
1) Occipital force:
High pull Head Gear traction force exerted from
above the occlusal plane and thus has both
distallizing and intrusive effects.
Other uses like:
(a) Can be used for vertical control of molars
(b) Dental open bite tendencies
(c) Hyper divergent skeletal problems
(d) Biomechanical system that tend to extrude molar.

Biomechanics involved are,
- Outer bow is same length as inner bow.
- Inner bow is passive in inner tube and outer bow is
bent so that point of force application is above
the CR of upper molars.
- This inclines the molars roots distally and intrudes
upper molars.
- In combination of cetlin plate occipital headgear
produces bodily movement of molars.

2. Cervical force:
Cervical force traction is exerted from below the
occlusal plane and has extrusive as well as distalizing
effects.
Used in cases involving
(a) Deep dental bite;
(b) Skeletal hypodivergent type;
(c) Vertical control of upper molar is not necessary.
Outer bow is longer than inner bow; outer bow is
bent so that force application is above the CR of upper
molars to produce backward and downward movement
of upper molars. Combined with removable plate to
produce bodily movement of molars.www.indiandentalacademy.com

Clinical management of Head Gear:
Before application of the Headgear, rotations of
molars should be corrected so that face bow is
fitted without any difficulty by using transpalatal
bar. If face bow is fitted along with TPA, the inner
bow should fit passively, if there is no palatal bar,
inner bow should be constricted for high pull and
expanded for low pull Head Gear so that it
contracts/prevents the upper molars from rolling
out/in.
Face bow must lie on lower lip, so that when
traction is applied, it lies directly at labial rim so
that patient discomfort is avoided.

I. Maxillary:
(B) Intra oral :
1.K- loop molar distallizer
Introduced by Dr.Varun kalra in 1995.

Components:
1 - 0.017’’ x .025” TMA
wire K loop
2 - Nance button to resist anchorage.
TMA can be activated twice as much as stainless
steel before it undergoes permanent deformation,
and the loop made of TMA produces less than half
the force of one made with stainless steel.

Each loop should be 8 mm long 1.5 mm wide. The legs of
‘k’ are bent down 200
and inserted into the molar tube and
premolar bracket.

The 200
bends in the appliance legs
produce moments that counteract the tipping
moments created by the force of the appliance
and these moments are reinforced by moment
of activation, as the loop is squeezed into place.
Thus the molar undergoes a translatory
movement instead of tipping. Root movement
continues even after the force has dissipated.

Premolars move approximately 1 mm
forward during 4 mm of molar distalization;
this is similar to the anchorage loss in
magnets and NiTi coil spring use. If,
necessary anchorage can be reinforced by
headgear.

Advantages:
-- Simple yet efficient
-- Controls the moment to force ratio to
produce bodily movement, controlled or
uncontrolled tipping as desired.
-- Easy to fabricate and place
-- Hygienic and comfortable for the patient
-- Requires minimal cooperation from the
patient
-- Low cost.

I. Maxillary:
(B) Intra oral :
2.Pendulum Appliance
Introduced by Dr.Hilgers in 1992.

It is a hybrid appliance that uses a
large nance acrylic button in the palate
for anchorage, along with 0.032” TMA
spring that deliver a light, continuous
force to the upper 1st
molars without
affecting palatal button. Thus, the
appliance produces a broad, swing or
pendulum of force from midline of the
palate to the upper molars.

Appliance design:
1*Pendulum Spring (.032” TMA): It is recurved and has
a molar insertion with a small horizontal adjustment
loop, a closed helix and a loop for retention in the
acrylic button.
2*Maxillary 1st
molars are banded with .036” lingual
sheath welded on them.
3*Nance button : The palatal acrylic helps provide
anchorage as well as retention for the pendulum springs
and must be made as large as possible to prevent any
tissue impingement.

The pendulum spring produces a light
continuous force on the maxillary 1st
molars.
The spring can also be adjusted to expand and
rotate the max 1st
molars. The .032” recurved
molar insertion wire fits into the .036” lingual
sheath on the max 1st
molar band. It is vital that
this wire can be torqued during the adjustment
and activation of the helix loop, which could
adversely affect the maxillary molars.

Appliance fabrication:
First premolar and molar are banded and lingual
sheaths are welded on 1st
permanent molar . 0.036” stainless
steel wire are adapted on the lingual side of the premolar
and is soldered to the bands.Two pendulum springs with
0.032” TMA wire is adapted along the palate. At this point
there should be a clearance of about 3 mm between the
spring in the midline, other wise after full activation the
spring tends to over ride. The spring should not meet with
the palate at any point and should be kept well away.

The palatal wire should be kept 2 mm
away from the soft tissue and should be
large. It is polished then premolar bands
are cemented followed by molars. For
adjustments and placing of loops into
lingual sheath use weigngart utility plier.

Stabilization:
1.Nance portion is removed and full upper fixed
appliance is bonded. An upper utility arch holds the
molars back with the incisors as anchorage. The buccal
segments are then retracted, usually with elastomeric
chain, to consolidate the spaces that have been opened.
2. After removal of pendulum appliance, a smaller,
easier to clean Nance button (Insta Nance) is placed
immediately, which is bonded.
3. The entire upper arch is bonded/banded and a
continuous arch wire with omega loops mesial to the
upper 1st
molar tube is placed.
4. A headgear is worn for a few months, while the buccal
segments drift distally.www.indiandentalacademy.com

Diagnostic Criteria:
1*Anterior open bite caused by this appliance, which is
a problem in Dolicofacial type, can be prevented by
directional headgears, conservative Xn
, palatal bonds.
2*If expansion is needed mid palatal jackscrew can be
incorporated into the center of nance portion –
“PEND-X” force produced is 200 to 250 Gms.

Modified pendulum appliance/M-pendulum:
It was introduced by Dr. Scuzzo et al in the year 1999. This
was designed to overcome the unwanted tipping of maxillary molars
during distalization.
In modified pendulum appliance the horizontal pendulum
loop is inverted, so that it will allow bodily movement of both the
roots and crown of the maxillary molars. Once distal movement has
occurred, the loop can be activated simply opening it. The activation
produces buccal and/or distal uprighting of the molar roots and thus
a true bodily movement, rather than a simple tipping or rotation.

The springs are activated before placement, to about 40-
450
with a weingart plier, resulting in about 125 g of force
on each side. The inverted loop should not be adjusted
until the spring has deactivated following each phase of
distalization.
Advantages:
1. True bodily molar movement
2. Minimal dependence on patient compliance
3. Ease of fabrication
4. Little need for reactivation
5. Patient acceptance.

I. Maxillary:
(B) Intra oral :
3.Jones Jig
RECHARD D. JONES AND WHITE ,IN 1992.

The appliance design consists of open coil nickel
titanium spring. The NiTi coil spring is slide over a .
036” main frame, which has accessories for the
attachment to the headgear tube and the arch wire slot
in the triple tube of the upper molar.
An eyelet tube is then place anterior to the spring,
such that when the eyelet tube is pushed distally the
NiTi coil spring gets compressed exerting a distalization
force on the molars.

Appliance fabrication and installation:
Maxillary 2nd
bicuspids are banded, nance button is
constructed & soldered to the lingual of 2nd
bicuspids and
maxillary 1st
molar are banded. Buccal arch form
contoured into the .036” jig main frame, placing it close to
the cuspid to avoid lip irritation. The appliance is
assembled by placing the spring followed the sliding
eyelet tube, the last 5mm of the .036” frame is annealed.
This is rolled over into a comfortable loop/stop.www.indiandentalacademy.com

Advantages:
1*No patient Cooperation required.
2*A typical Cl-II can be corrected in 4-6
months.
3*Can be used unilaterally.
4*No vertical components to the force
system.

4.Distal Jet
I. Maxillary:
(B) Intra oral :
Introduced by Dr. Carano and Dr. Testa in the year 1996.

This was developed to overcome the
disadvantages of other appliances.
Advantage of Distal Jet:
1. Improved esthetic and comfort
2. Simple insertion and activation
3. Ease of conversion to Nance holding arch for
maintenance
4. Simultaneous use of full bonded appliance.

Appliance Design:
Bilateral tubes of .036” internal diameter are attached to
an acrylic nance button. A coil spring and a screw clamp are
slide over each tube. (NiTi coil springs of 150 gms of children
and 250 gms for adult, appliance can be made of stainless steel
spring) The wire extending from the acrylic through each tube
ends in a bayonet bends that is inserted into the lingual sheath of
the 1st
molar band. An anchor wire from the nance button is
soldered to bands on the second premolars.

MODIFICATIONS OF
DISTAL JET

a. Double set screw distal jet :
This modification permits easier,
cleanser and more reliable conversion to
a molar Nance holding Arch, by
incorporating two set of screws.

b. Conversion to Nance holding arch:
Upon completion molar distalization, the distal jet
is converted to a nance holding arch to prevent
further distal movement and consequent
anchorage loss. The other ways to prevent or
stop movement of bayonet wire through the
tube is to –
(i) Flow a light cured acrylic around the coil
spring, over the distal bayonet bend and over the
activation collar to produce a solid extension
from the molar bands to acrylic button.

(ii) Wrap on 0.014” stainless steel ligature wire
around the end of the doubled back wire and tie
around the tube just mesial to the activation
collar.
(iii) The coil spring should be compressed
completely and the setscrew tightened to
prevent mesial movement of the molars.
The tube can also be crimped around the
mesial portion of the bayonet wire, but this
might weaken it enough.

5.Molar Distallization
Bow
RAKOSI, in 1992.
I. Maxillary:
(B) Intra oral :

The molar distalizing bow (MDB) guarantees
controlled distal movement of the molars. It is easy to
handle, can be removed at anytime and can be worn almost
full time. There is not risk of injury by wearing the appliance.
Shape and functioning of the MDB:
The appliance consists of a 0.8-1.5mm thick
thermoplastic splint extending into the buccal sulcus. The
distalizing bows fits into the anterior slot. The force can be
generated either by coil springs around the bow or by loops
within the bow itself. The amount of distal movement can be
regulated with adjustable stops. In its inactive state the
central section of the MDB lie approximately 2mm in front of
and 1.5mm above the anterior slot.

To activate the appliance the central section of the
bow must be fitted in the anterior slot by manual
pressure against the elastic resistance of the springs and
loops so that the force generated is transmitted to the
molar tubes. The molar tubes must be in the some plane
as the anterior slot or just above it.
The appliance can also be used for unilateral 1st
molar distalization, even after initial eruption of II molar.
It is primarily used after attempt to distalizing with
conventional means have failed.

-Due to design and function, the appliance cannot
intrude molars.
-A longer daily wearing time is 17-18 hr/day.
Advantages :-
It does not interfere with sleep, it can be removed
at any time and there is virtually no risk of injury.
Sufficient oral hygiene can be realized by cleaning
the removed thermoplastic splint and the bow with a soft
toothbrush and toothpaste.

6.Jasper Jumper Appliance
I. Maxillary:
(B) Intra oral :
Introduced by Dr. James. J.Jasper , in 1995.

It is similar in concept to the Herbst appliance
and is used in conjunction with fixed appliance.The
jumper mechanism, which is available in a number of
pre-selected sizes, is attached to the maxillary face
bow tube through the use of a soft wire with a ball on
one end. The amount of mandibular advancement is
adjusted by lengthening the maxillary connecting wire.www.indiandentalacademy.com

The jumper mechanism fits over the lower arch
wire.
A small acrylic ball is placed adjacent to the
bayonet bend and then the arch wire is placed through
the hole on the anterior portion of the jumper.
A heavy arch wire is used in the mandibular
dental arch in order to maintain lower anchorage.
There is also a danger of lower incisor
proclination if the arch wire is not tied back.
Usually 6-9 months of jumper wear is necessary
in order to correct a mild Cl-II problem in patients who
still have some growth remaining.

7. Super elastic NiTi wire
GIANELLY in 1998.
I. Maxillary:
(B) Intra oral :

In this procedure a 100gm (Neosentalloy) super elastic
Niti Wire with shape memory regular arch form is placed
over the maxillary arch. 3 points are marked as follows
on each side.
1. At the distal wing of 1st
premolar bracket.
2. 5-7mm distal to the anterior opening of the molar
tube.
3. Between the lateral incisors and canines
A stop is crimped to the arch wire at each of the
posterior marks and hooks are added for intermaxillary
elastics between the lateral incisors & canines.

The wire is inserted into the molar tube
until the posterior stop abuts the tube. The
anterior stop is grasped and the wire is forced
gently distally so that it abuts the distal wing of
1st
premolar bracket then ligated and is placed
through the 1st
premolar bracket. Since the wire is
5-7 mm longer than the available space the excess
will be deflected gingivally into the buccal fold.

With this appliance 1st
molars can be
distalized 1-2mm/month. If the 1st
molars are
not moving at this rate, a 200gm, 0.017”X 0.025”
Neosentalloy wire can be placed. Main
advantage of this wire is that, it is easy to
inserted even after all teeth have been bonded.

8. Molar distallization
using NiTi coils

This system uses 100gm super elastic coils to move
maxillary molars distally using this with little / no
patient cooperation, molars can be moved distally 1 to 1.5
mm/month with 8 to 10 mm activation of the 100gm
coils that is used in conjunction with fixed appliance.

A passive 016x022 inch wire stops at about the
incisal wings of premolar bracket is inserted and the
coils are placed on the wire between the 1st
premolar
& the molars the coils are activated 8-10 mm by
compressing and maintaining them against the
molars by crimpable hooks or gurin locks.

I. Maxillary:
(B) Intra oral :
Developed by Dr. Fortini, Lupoli, & Parri, in 1999.
9. First class appliance

As the distal jet appliance produced anchor loss as the
molars are distalized, to overcome this 1st
class
appliance was developed.
It can be used for both unilateral and bilateral
distalization with minimal anchorage.
Appliance Design:
Bands are placed on the maxillary 1st
molar and on
either maxillary Second premolar or 2nd
deciduous
molars. Impression is taken with these bands in place
and a working cast is poured.

The laboratory procedure is carried out as follows:
1. Vestibular
components:
Formative screws are soldered on the buccal sides of the 1st
molar bands occlusal to 022” x 028” single tube so they will
not interfere with subsequent insertion of the arch wire.
Split rings welded to the second premolar or second
deciduous molars bands, control the vestibular screws.
Stop screws are used to maintain the distal positions of the
molars after active movement has been completed.www.indiandentalacademy.com

2. Palatal components:
In the palatal aspects the appliance is much like modified
nance button, but is wider and has a butterfly shape for added
stability, and support during retention. The embedded .045” wire
should be in single sections without welded joints to prevent
breakage . 045” tube are soldered to the palatal side of the 1st
molar bands for insertion of the butterfly component of the
appliance.
These tubes allow the molars to be distalized without undesirable
tipping. The butterfly section is soldered to the second bicuspidwww.indiandentalacademy.com

Nickel titanium .010”x045” coils springs
approximately 10 mm each in length, are fully
compressed between the bicuspid solder joints and the
tubes on the deciduous molar or second premolar bands.
These springs are designed to balance the action of the
vestibular screws, preventing molar rotations
development of posterior crossbite.
About 4-8mm of molar distalization can be
achieved in 28-95 days with this appliance. After
distalization it can left in place as an anchorage unit
maintain the space.

I. Maxillary:
(B) Intra oral :
10. Modified Cetlin
Appliance

The removable distallizing plate is used
to continue distallization of the upper molars
when a super Class I relationship cannot be
obtained using headgear.
Gentle force of approximately 30gm with
minimal reaction on upper front teeth, usually
they incline molar crowns distally and extrude
the molars. For this reason it is used along
with extra oral force.

The plate is composed of the following three parts:
1. The active part: 0.028” stainless steel distalizing spring.
2. The retention part: An anterior 0.017” X 0.025” arch covered
by a labial screen and having 2 Adams clasps on the 1st
premolars/the 1st
deciduous molars.
3. The anterior Bite plane: Disocclusion aids in distal
movement of upper molars and in leveling the curve of spee
by lip bumper.

Clinical management:
- Worn 24 hr/day except during meals
- Always used with extra oral force.
- An activation of 1 to 1.5 mm/side gives
approximately 30 g of distal force either
bilaterally or adjusted on alternative sides.

•Wilson distalization
mechanics:
Wilson and Wilson (1988)

• The Bimetric distalizing arch is used to
produce distal movement of maxillary
molars. This arch is Bimetric in that the
anterior segment is made from 0.022”
stainless steel. An elastic hooks are
attached to the posterior segment in the
region of the upper canines. An omega
shaped stop is located in the premolar
region.

• A 0.010” x 0.045” open round coil spring
is placed between the distal leg of the
omega stop and the face bow tube is located
occlusally,
The distalizing force on the molars is
produced by the compression of the push
coil spring anchored by the pull of Class-II.
The force of the elastics counteracts the
force of the push coil springs so that the
anterior segment of the Wilson arch
approximates the incisor bracket before
ligation to anterior teeth.

I. Maxillary:
(B) Intra oral :
11. Transpalatal arch
By Robert A Goshgarian
in 1972.

This type of arch, which spans the palate between
the upper I molars, has been shown to be effective as an
anchorage maintenance device by Nell as an active
orthodontic appliance.
Uses of the TPA:
TPA has several functions including
- correction of molar rotation,
- molar stabilization or anchorage and
- molar distalization as well as other molar
movements.

Indications:
Indicated in whom severe malocclusion are going to be
corrected.
Contraindications:
- Most class III non-surgical cases
- End-to-End molars contraindicate the use of a TPA in
upper premolar extraction cases
- Use of TPA as a molar rotating appliance also is
contraindicated in Class III patients in whom
orthognathic surgery is not under taken eg: in whom
permanent teeth are not extracted.

Delivery & Activation of TPA:
Before cementing the TPA clinician should make
sure that the buccal tubes are parallel to each other and
to the mid saggital plane and that the occlusal surfaces of
the molar bands are parallel.
Activation:
Cetlin (1992) has stated that distallization of one
upper 1st
molar can be achieved by unilaterally activating
only one arm of TPA and the other arm is rotated into
position producing a distalizing force. Same adjustment
should be made on the opposite side six to eight weeks
later.

Asymmetric
distallization
with a TMA
transpalatal arch
( MASSIMILIANO,in
2001)

This is a modification of Cetlin’s technique. It reduces
Rx
time and improves the efficiency of unilateral maxillary
molar distillization.
Appliance Design:
TPA made from .032” TMA bar. TMA is more elastic
and resilient than stainless steel and is used to make
conventional Goshgarian arch. The direction of insertion of
TPA into tubes is also different. The arch is inserted from
distal into the tube of maxillary molar used as anchorage, and
from the mesial into that of the maxillary molar to be
distalized. This makes the TMA arch more effective, because
the end inserted from the distal is more posterior than the end
inserted from the mesial. When activated, the arch applies a
mesiobuccal rotation to the anchor molar and a distally
directed force to the opposite molar.

The TPA can be constructed by a laboratory or in
the office using a weingart or similar plier. The central
omega loop is not needed because the TMA arch is not
being used for palatal expansion. If expansion is
required it should be carried out in advance using a
traditional TPA or other method.
The TMA arch is reactivated monthly by bending
the end inserted from the distal about 300
.www.indiandentalacademy.com

I. Maxillary:
(B) Intra oral :
12. Upper molar distallization
in Begg treatment

In this method, the Bimetric arch principle of
Wilson is gainfully employed. By using this method
about 2 mm of arch length on each side can be gained by
distalizing the upper molar, which helps in reliving
moderate crowding in upper arch in growing child.
This method not only distalizes the upper molar
but also expands the upper canine, premolar area,
besides opening the Ant. Deep bite so this method is
especially useful in Cl-II correction of dental arches.

Arch wire design:
The upper arch wire is made in 016” premium
wire, the arch wire is shaped in an ideal form and there
are no loops in the anterior area.
The cuspid circles are kept abutting the cuspid
brackets – 2 pear shaped loops (one on each side) are
made touching the molar tubes.
About 450
bite opening is placed. Equally distributed
on either side of loop, a molar segment is given a wild
toe in.

The arch wire is activated by opening the
loops by 2 mm each time. This causes an
expansion in labial and buccal directions in the
incisor and canine, premolar area respectively;
the former is resisted by using Cl-II on Elastic
load reduction principle, so as to transfer
stranger force i.e. distal direction to the molar.
The later is utilized for expanding the canine
and pm area when necessary.

Elastic load reduction principle:
The patient is asked to use green elastic for a
week, pink elastic for 1 week and then yellow elastic
for 2-3 weeks till the next appointment. Initial heavy
elastic force of newly activated arch wire thus
transforming into the molars in the distal direction.
As the molars become up righted/distally displaced
the arch wire force gradually diminishes. It is then
supported by correspondingly lesser force of pink
elastics and finally by the light forces yellow elastics.

Thus the extrusive component of Cl-II is kept
to a minimum level most of the time. Also have
forward drag on the lower arch is reduced quickly
and maintained at a minimum level. About 1 mm
distal movement of upper molar can be
achieved/month. The arch wire is activated for 3-4
visits for required amount of correction.
Employing this procedure suitable border
line cases can be converted to non xn
Rx
thus this
procedure can play a very important role in the
late mixed dentition/early permanent dentition non
xn
Rx. www.indiandentalacademy.com

I. Maxillary:
(B) Intra oral :
13. Denholz appliance

It is the one, which uses muscle anchorage
to distally drive the 1st
permanent molars.
Denholz appliance consists of molar bands with
horizontal round buccal tubes, a base arch wire
of .036” or .040” steel to fit the buccal tubes and
a labial vestibular screen. Coil spring sections
are added to the arch wire so that when the wire
labial screen assembly is inserted into the tubes,
the screen stands away from the anterior teeth.

The wire and coil spring assemblage is
usually worn only at home and during night,
but it may be tied in place and worn at all
times, if desired. The coil spring is attached to
the acrylic labial screen, so that it is not lost
through patient manipulation. If the patient
exercises, one to two hours a day forcibly
closing the lips over the labial screen will
accelerate RX sequence.

I. Maxillary:
(B) Intra oral :
14. Modified Nance appliance
for unilateral molar
distalization

The appliance is a modification of the traditional
Nance holding arch. The Class-II side of the .036”
stainless steel wire frame work is finished with an
anteriorly projecting arm like that of a quad helix, this
arm is designed to resist the horizontal moment that
would rotate the molars distally and cause expansion in
the bicuspid region.

The active Cl-II side also has an arm bent
similar to a quad helix with the most anterior terminus
soldered to a 1st bicuspid band. A 0.022” omega loop
was soldered to the anterior end of the framework,
which allowed the distal end of the loop to slide.www.indiandentalacademy.com

Distally as it is opened for activation 0.045” tube is
soldered in the lingual side of molar and the frame work
is passed through it and a 10 mm 0.009” X 0.036” open
coil spring is added to the frame work arm between the
omega loop and the 1st
molar band assembly so that the
frame work assembly could slide and other side of the
frame work is soldered to the 1st
molar band. After
cementation of the appliance, the omega loop is opened
enough to compress the coil spring to a length of 7 mm,
which will deliver a force of 150 g, at succeeding
appointment spring is measured to ensure it is kept at 1
mm compression.

When the molar being moved distally achieved a
Cl-I relationship, the lingual molar tube is tied back to
the distal helix with a metal ligature and the part of the
appliance anterior to the molar is removed. This molar
anchorage allows possible retraction of the anterior
teeth while maintaining molar position.

Dr. Martin Puente in the article “Cl-II correction with
an edgewise modified Nance Appliance.” describes the
biomechanical action of modified Nance. According to
him there are 4 stages:
1st
stage: (Mainly distalization of molar.)
- Initial upper arch wire is rectangular Neo sentalloy
* NiTi coil springs in between 1st
premolar and molar
region buccally as well in palatal wire framework
omega loop and lingual sheath.
- *Anchorage by anterior dentition and nance button
- * Coil springs activated to produce distal movement of
about 0.75-1 mm/month.

2nd
Stage: (Retraction of 2 nd premolar)
-* Nance appliance kept passive by tying ligature wire
from lingual molar tube to Nance helical loop.
-* Round .016” or .018” stainless steel wire with omega
loop mesial to 1st
molar. These loops are bent with tip
back and toe in to reinforce the molar anchorage and
control premolar rotations.
-* Second premolars are retracted by tying ligature wire
to molar hook.

3rd Stage: (Retraction of 1 st premolar)
* Anterior portion of nance is cut off and
adapted to bend in 2nd premolar region to
preserve anchorage.
* 1st premolars are retracted by using E-
chain, medium neo sentalloy coil spring or
ligature wire.

4th
stage: (Space closure)
Nance button removed, for anterior retraction is done.
Space closure is achieved with a 0.017” X 0.025”
double ‘T” arch wire. Canines are moved first
followed by incisors. The final result will be Cl-I
molar and canine relationship ligated to the
attachment on the buccal aspect of the anchor tooth.
Approximately 3 mm of the mounting wire should
extend beyond the distal portion of the buccal tube
and is then bent in lingually, to avoid any buccal
irritation.

I. Maxillary:
(B) Intra oral :
15. Lokar appliance
in 1996

This appliance utilizes the continuous ideal
force nickel titanium spring to generate rapid
molar movement while minimizing patient’s
discomfort.
In planning the anchorage system, rigidity is
mandatory and equally important is the
distribution of the reactive force generated by
the appliance over a large area of the palate,
which is the area of greatest curvatures.

Anchorage system consisted of 0.036”
steel wire adapted to the palate, which is
soldered to the anchor bands on the second
bicuspids large acrylic button, approximately
½ inch diameter in the area of greatest
curvature & an attachment on the buccal
aspect of anchor bend.

Rectangular part of the distal end of the
lokar appliance is inserted into the 1st molar
buccal tube. It should be parallel to the
occlusal plane. Appliance is activated by
compressing the nickel titanium coil spring by
using a ligature tie from the bracket on the
anchor tooth and the sliding part of the lokar
appliance.

I. Maxillary:
(B) Intra oral :
16. Magnetic distallization
appliance
Gianelly and Vaitas in 1994.

Repelling magnets to Distallize molars :
This system consists of;
* Miniaturized cylindrical samarium cobalt magnets
encased in a steel sleeve each magnet with a finely
machined hole in the center and coated with a
biocompatible polymer to avoid leach out products
** .016” stainless steel wires with a bent stop near the
distal end and small helix at the mesial end. Both
repelling magnets on each side are held together
by a clamp to avoid possible loss of magnets before
insertion.

Before insertion of magnets, it is necessary to
fabricate a palatal anchorage system. When we
insert the magnets in a repelling configuration the
distal magnet moves molar distally while the mesial
magnet generates a reactive anterior force & this
reactive anterior force are controlled by palatal
anchorage system.

17. ACCO (acrylic cervical
occipital appliance)
I. Maxillary:
(B) Intra oral :

- Developed by Dr. Margolis

The appliance consists of a modified
Adams clasps on the 1st
premolars, a labial bow
across the incisors for retention and finger
spring against the mesial aspects of the 1st
molars. 1 mm bite plate to disocclude posterior
occlusion for the distal movement of molars.
Activation: one half a cusp width, not more than
100 to 125 gms of force.
Used 24 hrs/day.

Original appliance:
Consisted of a labial bow in which helices are
included between lateral and central incisors. A straight
pull or northwest headgear was inserted into the helices
and was worn at night in conjuction with the appliance.
There was no modified Adams clasp and only one finger
spring for one molar. If bilateral molar distallization was
desired, 2 appliances were necessary.www.indiandentalacademy.com

Advantages:
1. Applies a constantly acting force to enhance
the rate of molar movement.
2. Patients readily accept the appliance. i.e. it is
intra oral and relatively comfortable to wear.
3. Effective method to distalize molars
asymmetrically.

Disadvantage:
.Tipping movement of molar
Remedy:
* Overcorrect molar crown position
* High pull headgear on molars in conjunction
with the ACCO as advocated by Cetlin and Ten
Hoeve.
* Anchor loss (30 to 40% of anchorage loss + 2
mm increase in overjet with 4 mm of distal
movement).

Anchorage control:
- *Lower – lip Bumper
- *Upper – Bonding on incisors and advocating
Cl- II elastics
- *Palatal Anchorage.

18. Distallization using
microimplants.
I. Maxillary:
(B) Intra oral :


Traditional method of controlling
anchorage during molar distallization tends
to cause unwanted tooth movement of other
teeth and require patient cooperation.
These disadvantages can be over come with
skeletal anchorage, which is gradually
gaining acceptance among orthodontists.

Clinicians have assumed that the palatal bone
appears thin on a lateral cephalogram, a wider mid
palatal implant or a disc type of implant is required. If
the palatal area is examined in 3D, the available bone
support is greater that it appears cephalometrically.
The nasal crest between the ANS & the PNS is 2 mm
thicker as it appears on lateral ceph. The nasal crest
has a triangular shape with a base of 5.4 mm and a
height of 5.6 mm in the average adult , which is large
enough for miniscrew.

Except in the incisal canal, the
midpalatal consists of cortical bone that is
sufficient to support an entire miniscrew, so
that the screw will not be affected by
orthopedic force. In addition there are no
roots, nerves/blood vessels in the palatal area
to complicate surgical screw placement.
Most of the soft tissue is thinner than 1 mm
ensuring accurate placement of miniscrew is
easily removed.

Procedure:
A screwdriver in a contra angled hand piece
is required and it must be longer than the depth
palate to avoid contact with the maxillary anterior
teeth. As the cortical bone can be damaged rather
easily by frictional heat and screw should be
inserted with irrigation at a rate of no more than 30
turns/minute.
From the mini screw to the TPA hook , a
power chain is attached for distallization.

19. Removable molar
distallization splint
I. Maxillary:
(B) Intra oral :


The removable molar distallization splint that can
achieve better cooperation than other alternatives.
Appliance Design:
The clear splint is made from 1.5mm Biocryl in a
Biostar machine.
Two internal clasps are used for retention premolars are
banded and 0.045” tube is fixed to it and 0.036” stainless
steel wire is attached to the splint in the pm region so that it
extends 3 mm beyond the tube and a nickel titanium open
coil spring produces about 220gm of distal force at the
beginning of RX the coils are reactivated.

In cases of excessive overbite with the molars in
full occlusion where distal molar movement is
considered difficult. This splint creates a separation of
1-2mm between the maxillary and mandibular molars
at the beginning of RX eliminating lateral occlusal
forces.
The maxillary molars usually move distally about
1.5-2mm/month.
After molar distallization, the splint can be used
to maintain molar position while the anterior teeth are
retracted.

20. Molar Distallization
System (MDS)
Gianelly in 1988.

I. Maxillary:
(B) Intra oral :


Molar distallization system uses two
opposing magnets for each maxillary
quadrant. The mesial magnet of each pair is
mounted so that it can move freely along a
sectional wire. A sliding yoke, with ligation
hooks mesial to the mesial magnet brings the
repelling magnets together to activate the
magnetic force.

Using this appliance the molars moves
almost bodily with slight distal tipping and
rotation.
When the magnets are in contact with each
other it produces a force of 220g after a tooth
movement of 2 mm, which is normally, achieved
with this system in a 3-week period the force
drops to approximately 60gms.

21. Crozat treatment

I. Maxillary:
(B) Intra oral :


The basic philosophy of crozat Rx
is
that, if the oral tissues can be given
enough time to respond, mild pressure
over longer period of time will produce
tooth movement without excessive
tipping.

The basic crozat approx consists of following parts:
1. Crib (0.25” - 0.28”) attaches firmly to teeth,
usually 1st
molars.
2. Clasp wire (0.22”-0.25”) engages undercut on
crib tooth for retention.
3. Body wire (0.040”-0.051”) connects right and left
sides and stabilizes appliances.
4. Lingual arm (0.028”-0.32”) serves for attachment
of finger springs, can also be used to expand
bicuspids.
5. Buccal arm (0.036-0.45”) serves for attachment of
labial wires.

Cl-II Division Rx
:
Basic crozat Cl-II division Rx
can be
divided into phases
1. Molar rotation
2. Molar relationship
3. Bicuspid relationship
4. Cuspid relationship
5. Anterior relationship.

22.Fixed piston
appliances

I. Maxillary:
(B) Intra oral :


This appliance produce bodily movement of
maxillary 1st
molars without extra oral appliances and
with no loss of posterior anchorage.
The appliance components are:
1. 1st
molar and 1st
bicuspid bands.
2.0.036” stainless steel tubing (soldered to the
bicuspids)
3.0.030” stainless steel wires (soldered to the 1st
molars)
4.Enlarged Nance button, reinforced with an 0.040”
stainless steel wire (for control of anterior anchorage)
5.0.055” (internal diameter) super elastic Niti open
coil springs www.indiandentalacademy.com

Rx
:
1.Once the desired arch length development has been
achieved, remove the buccal assemblies. Remove the
bicuspid band material except for the lingual solder
joint leaving in essence, a space maintainer.
2.Bracket the maxillary arch & begin retraction of the
bicuspids and cupids.
3.Use uprighting springs in the vertical bracket slots to
obtain proper axial root inclination.
After retraction and uprighting remove the modified
Nance button and begin intrusion and retraction of the
anterior segment.

The fixed piston appliance has the following
advantages,
·Produces bodily movement of the max. 1st
molars
with no loss of posterior anchorage.
·Does not require patient compliance for molar
distallization, but allows the use of headgear if
needed. Only proper oral hygiene is required of the
patient.
·Reduces Rx
time in non-xn cases.
.Uses a light, controlled force of only 150gm per
tooth.
.Does not interfere with the occlusal plane, thus
maintaining control of the vertical dimensions.

23. The lingual distallizer
system
I. Maxillary:
(B) Intra oral :

Introduced by Carano, Tesia and Siciliani in 1996.

Appliance description:
The active components of the lingual
distallizer are two bilateral 0.9 mm tubes connected
to a Nance appliance. A bayonet wire is inserted into
the lingual sheath of the 1st
molar bands. On the tube
there is a stainless steel coil spring and a clamp. The
clamp can slide towards the molars and can be
tightened in order to compress the coil.

The force exerted by the spring begins at
180 g and decrease as space is opened.
Consequently, the TP is reactivated by sliding
the clamp closer to the molar once in a mouth.
A molar band and button attachment or a
directed bonded button in cases of partial tissue
impaction.

Maxillary Expansion:
Maxillary expansion can be achieved by
embedding jackscrew in the palatal button.
Molar rotation:
3-5 simple helical loops in the bayonet wires
of the distal jet can be used to produce molar
rotation, by activating the loops with the utility plier
before seating the bands. E chain is extended from
bicuspid bands to molar bands to hold them in
position during insertion of the preactivated
appliance.

24. C-Space regainer for
molar distallization
I. Maxillary:
(B) Intra oral :

Introduced by Kyu-Rhim Chung, Young-Guk Park
and Su-Jin

C-Space regainer is an removable appliance used
to achieve bodily molar movement without
significant incisor flaring.This appliance can be
used to intrude the teeth as well as to move them
distally or sagitally.
INDICATIONS:
a) Mesial drift of first molar following premature
loss of the deciduous molar in the mixed
dentition.
b) Mild arch length discrepancy treated by
extraction of second or third molars ( with
straight or flat facial profile)

c) Open bite
d) Class II malocclusion
e) Class III malocclusion

II. Mandibular
1. LIP BUMPER
By Denholtz.

The lip bumper is a fixed functional
orthodontic appliance. It works by altering
the equilibrium between the cheeks, lips
and tongue and by transmitting force from
periodontal muscles to the molars where it
is applied. The lip bumper is used for
various purposes like,
· Molar anchorage
· Therapy of habits
· Space gaining in the lower arch.

Cetlin has described 2 different types of lip
bumpers:
1. Custom made for each patient containing 2
loops at the molar level that allow
modification
of the appliance.
2. Preformed & available in different sizes. It
has 4 loops, two at the molar level and two at
the canine level. Two additional loops give a
better shielding effect in the canine region
and allow the use of Cl-III elastics in morewww.indiandentalacademy.com

Fitting the lip bumper:
The lip bumper should be wider buccally and
flatter anteriorly than the natural arch form. It
is designed to produce because the
dentoalveolar widening and reshaping are
induced by the tongue and lip bumper without
direct appliance force except for the contact at
the molar tubes.

The guidelines for obtaining optimal
adaptation of the appliance are:
1. Transverse position: The wire must be 2
mm from the lower canines and 3 to 4 mm
from the Premolars (4 looped better)
2. Sagittal position: Not be more than 1 to 2
mm away from the labial surface of lower
incisors. This position offers good support
or the lower lip for the anterior seal without
rendering the appliance uncomfortable.

3.Vertical position: In the lateral segments,
the wire must be positioned generally at the
middle 3rd
of the premolars and canine
crowns.
In the anterior region depending on the
overbite, the bumper can be positioned at 3
different levels with different levels with
respect to the incisor crowns.

· Incisal edge: This position is used during initial
phase of treatment. It helps to upright mesially
inclined molars because the lower lip tends to lift the
anterior part of the bumper, creating a longer lever
effect on the molars.
· Middle third: This position is used when shielding
effect on incisor is desired.
· Gingival level: when one does not want to affect the
equilibrium between the lip and tongue.
The appliance must be worn 24 hours/day and
should be removed only for meals and hygiene.

II. Mandibular
2. FRANZULUM
APPLIANCE
Friedrich Byloff in 2000.

Gaining space in the mandible is
more difficult than in the maxilla.
Extra oral appliances are seldom
attached to the mandibular molars
because of the pressure they place on
the condyles.

Appliance Design:
The Franzulum appliances anterior anchorage
unit is an acrylic button, which should be at least 5
mm wide to avoid mucosal trauma and to dissipate the
reactive force produced by the distallizing
components. Rests on the canines and 1st
pm are
made from .32” stainless steel wire. Tubes between 2nd
PM and 1st
molars receive the active components. The
posterior distallizing unit uses nickel titanium coil
springs, about 18 mm in length, which apply an initial
force of 100-120 g/side.

A ‘j’ shaped wire passing through each coil is
inserted into the corresponding tube of the
anchorage unit. The recurved posterior portion of
the wire is engaged in the lingual sheath of
mandibular 1st
molar band.
The anchorage unit is bonded with composite
resin to the canines and 1st
premolar arm. The J
shaped distalizing unit is then ligated to the lingual
sheaths of the molar bands, compressing the coil
springs. Thus the active part of the appliance runs
lingually at a level close to center of resistance of the
molar, to produce as almost pure bodily movement.

CONCLUSION:
What was extraction case involving four premolars
yesterday can be handled effectively with distallization
procedures today. In addition orthodontists have realized that
the public now prefer fuller smiles and prominent lips as
compared to the standards of 1960s, with the recent trend
towards more non-extraction treatment.

References
• Hilgers JJ. The pendulum appliance for Class II non-
compliance therapy. J Clin Orthod. 1992; 26(11):706-14.
• Abu. A. Joseph and Chris. J. Butchart: An evaluation of
the Pendulum Distalizing appliance: Seminars in Ortho,
Vol. 6, 2, 2000 (129 - 135).
• Giuseppe Scuzzo, Kyoto Jakemoto, Flavia Pisani,
Stefano Della Vecchia : The Modified pendulum
appliance with removable arms: JCO, 2000:4: Vol. 34, 5.
• Byloff FK, Darendeliler MA. Distal molar movement
using the pendulum appliance. Part 1: Clinical and
radiological evaluation. Angle Orthod. 1997; 67(4):249-
60.

• Hilgers JJ. Hyperefficient orthodontic treatment using
tandem mechanics. Semin Orthod. 1998 Mar; 4(1):17-
25.
• Graber TM. Current orthodontic concepts and
techniques. In: Graber TM (Ed). Current orthodontic
concepts and techniques. Philadelphia: Saunders, 1969,
pp 919-988.
• Cetlin NM, Ten Hoeve A. Non extraction treatment. J
Clin Orthod 1983; 17:396-413.
• Hilgers JJ. The Pendulum appliance for Class II
noncompliance therapy. J Clin Orthod 1992;26:700-713.
• Gianelly AA, Bednar J, Dietz VS. Japanese NiTi coils
used for molar distal movement. Am J Orthod
Dentofacial Orthop 1991 ;99:564-566.
• Ghosh J, Nanda RS. Evaluation of an intraoral maxillary
molar distalization technique. Am J Orthod Dentofacial
Orthop 1996;110:639-646.

• Bondemark L, Kurol J, Bernhold M. Repelling
magnets versus superelastic nickel-titanium coils
in simultaneous distal movement of the
maxillary first and second molars. Angle Orthod
1994;64:189-198.
• Cetlin NM, Ten Hoeve A. Nonextraction
treatment. J Clin Orthod 1983;17:396-413.
• Pieringer M, Droschl H, Permann R.
Distalization with a nance appliance and coil
springs. J Clin Orthod 1997;31: 321-326.
• White LW. Current Herbst appliance therapy. J
Clin Orthod 1994;28:296-309.
• Miller RA. The flip-lock Herbst appliance. J
Clin Orthod 1996;30:552-558.

• Windmiller EC. The acrylic-splint Herbst appliance: A
cephalometric evaluation. Am J Orthod Dentofacial
Orthop; 1993:104:73-84:
• Bernstein L. The ACCO Appliance. J Clin Orthod; 1969
3:461-468
• Jones and White. Rapid class II molar correction with an
open –coil spring. J Clin Orthod; 1992: 10: 661-664:
• Valrun Kalra. The K-Loop Molar Distalizing Appliance:
JCO, 1995 : 5:299-301.
• Kloehn. Force or persuasion. Angle Ortho, Jan ; 1953,
Vol. 23, 1:61-65.
• Steiman. Visual Aid For Bonded Arylic Rapid Palatal
Expanders. JCO: Vol.xxxi, No.5: 1-8.

. Bondemark L, Karol. Distalization of maxillary
first and second molars simultaneously with
repelling magnets. Euro J Orthod;14:264-272:
1992
. Friedrich Byloff. Mandibular molar distalization
with the Franzulum appliance; J Clin Orthod;
9:39:2000

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Guide to Molar Distalization Techniques

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