Pendulum Appliance Molar Distalization Efficiency

Efficiency of Pendulum Appliance for
Molar Distalization Related to
Second & Third Molar Eruption Stage


Gero S.M. Kinzinger, Dr med dent et al

www.indiandentalacademy.com

1

Introduction







Head gear, ACCO, Jones jig, Lokar
distalizing apl, distal jet, magnetic modules
Pendulum appl – Hilgers, 1992
Snodgrass, Byloff, Favero, Scuzzo et al and
Kinzinger et al.
Bussick & McNamara, Ghosh & Nanda,
Joseph & Butchart – position of second
molar is of little if any import.

2

Objectives


To assess this hypothesis.



Discussion of early third molar germectomy.


3

Material & Methods





Modified Pendulum appl
36 pts – 25 girls, 11 boys
Mean age – 12 years 5 months
3 groups according to the stage of second &
third molar eruption – patient groups (PG)
PG1, PG2, PG3.


4

Material & Methods




PG1 – incomplete or no eruption of M2
PG2 – M2 erupted, M3 in budding stage
PG3 – M1, M2 erupted, M3 germectomy


5

Material & Methods






Pendulum appliance – Pendulum K

Activated intraorally by adjusting distal
screw
Built in straightening activatn & toe-in

6

Material & Methods


7

Material & Methods



Dental casts – T1 & T2
Transverse arch width and magnitude &
direction of molar rotations.


8

Material & Methods



Sagittal plane – cephalograms T1 & T2.
A. Skeletal angles–




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SNA
SN-NF
RFA
Facial PA
FMA


9

Material & Methods


B. dental angles & distances –



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i CEJ/PTV
M1-CEJ/PTV
M2-CEJ/PTV
M1-CEJ/ANS-PNS
i/ANS-PNS
i/SN
M1/ANS-PNS
M2/ANS-PNS
M1/SN
M2/SN

10

Results


Dental cast measurements



Pre Rx transverse arch width – M2>M1
Gain M2>M1


11

Results


Mesiobuccal rotations


M1>M2


12

Results


Analysis of Cephalograms




Mean distal tipping: M1 3.07+-4.02 ; M2 5.3+-4.23
Labial tipping of central incisor – 4.51+-3.6
Mean distalization: M1 3.14+-0.92 ; M2 2.56+-0.81
mm. Incisor protrusion 1.33+-0.85





70.25% and 29.75%

Time – 0.62 and 0.51mm/month
Distal tipping of first molars in PG1 > PG2 &
PG3. ( 0.8+-3.4 & 5.36+-3.49)

13

Results




Tipping of erupted second molars markedly
more in PG2 than PG3. ( 7.55+-5.28 & 2+-2)

None of the measured skeletal changes
were significant.


14

Discussion


In the distalization direction, a tooth bud
acts on the mesial neighboring tooth in the
same way as fulcrum.


15


16


17

Biomechanical analysis


18

Horizontal plane
Mesiobuccal rotation


19

Sagittal plane


21


22


23

Conclusions




The best time to start therapy with a
pendulum appliance is before the eruption
of second molars.
In case of simultaneous distalization of 1st
and 2nd molars, prior germectomy of 3rd molar
is strongly recommended.


24


25

Bond Strength of Various Bracket
Base Designs


Wei Nan Wang, Chung Hsing & others


26

Purpose of the study



Size & design of bracket base
Two designs :






A single piece casting with retention grooves
on the base.
Mesh or circular,concave form that is laser
welded with silver directly to the bracket
body.

To determine the bond strength and
debonding interface distributions of 6 types
of brackets.

27

Material & Methods


The brackets were –







Dynalock (Unitek, US)
Accuarch appliance Formula –R (Tomy,Japan)
Ultratrimm (Dentaurum, Germany)
Minidiagonali Roth (Leone, Italy)
Tip-edge Rx-1 (TP Orthodontics, )
Mini Diamond (Ormco)


28

Material & Methods


29

Material & Methods





120 maxillary premolars fm pts 9-16yrs
Criteria for tooth selection – a. crown with
no defect. b. tooth has never been
pretreated with a chemical agent such as
H2O2 or formalin. c. contour of labial
crown surface was adapted to the base of
the bracket before bonding.
6 groups of 20 teeth each.

30










Polished with pumice for 10 sec
Etched for 15 sec with 30% phosphoric acid
Outline demarcated with pencil
Surface outside coated with red nail polish
Bonding agent – Concise, 3M
Specimen incubated in 37* water bath for
24 hrs.
Tested on Instron universal machine

31

Results


32


33


34

Discussion


Tomy bracket



Dentaurum bracket


Mesh spacing -5.1

35



Mini mesh – 2.9


36

Conclusions






The size & design of a bracket base affects
bond strength.
Tomy bracket with circular concave design
produced greater bond strength.
Among brackets with mesh type bases, the
larger the mesh spacing, greater the bond
strength.


37


38

Distal Movement of Mandibular
Molars in Adult Pts with the
Skeletal Anchorage System


Junji Sugawara, Takayoshi daimaruya et al


39

Introduction







One of the most difficult to achieve
treatment objectives in Orthodontics.
Headgear, lip bumper, distal extension
lingual arch, Jones jig, Franzulum
appliance, multiloop edgewise archwire.
Skeletal Anchorage System ( SAS ).
Distalization of molars enables the clinician
to correct ant crossbites, crowding & dental
asymmetry without extracting premolars.

40

Aims






To measure the average amt of distalization
of mandibular molars.
To evaluate the type of tooth movement that
occurs.
To determine the stability of the distalized
molars 1 year posttreatment.


41

Material & Methods



15 adult pts ( 12 women & 3 men )
Criteria –








Having no severe skeletal disharmonies
Sufficient space behind the second molar
Treated by distalization of mandibular first molar
Followed for at least 1 yr posttreatment.

Average age – 26.9 yrs, 16.1 - 43.5 yrs
Average t/t time 28.9 months, 21 – 39 mnths

42

Material & Methods


43

Material & Methods






Anchor plates ( Leibinger, Germany) – pure
titanium
Monocortical screws – pure titanium –
diameter – 2.0 mm, length – 5.0 mm.
Placed behind second molars under local
anaesthesia.


44

Material & Methods


45


46

Methods of Distalization


Single molar distalization


47



En masse distalization of entire buccal
segments


48








Retention – LBR – 0.0175-in multistranted
flexible wire.
Records – Lat. Ceph, OPG, dental casts &
photographs – pre Rx, at debonding, 1 yr
after debonding.
Occlusograms – 1.06 X
Tipping ratio - root movement / crown mov



< 25% - tipping
>25% - translation

49

Crown movement –
occlusograms
 Root – ceph tracing



50

Results


51

Results








Mean distal movement : 3.5 +- 1.4 mm at
the crown level.
Max – 7.1 mm , min – 1.0 mm
Root movement – 1.8 mm
Relapse – 0.3 mm , 9%
Max relapse – 0.8 mm
No correlation betn relapse rate & amount
of tooth movement.

52

Case 3




36 yr Japanese woman
36 months of active treatment
Distal movement – Lt- 7.1 mm, Rt- 5.5 mm


53



Post treatment


54


55


56

Discussion






Previous modalities disadvantages – pt
compliance, tipping movement, anchorage
loss, incisor flaring.
Endosseous implants – disturbed tooth
movement, became loose because of heavy
force.
SAS – provides rigid anchorage, doesn’t
interfere with tooth movement.

57



Two distinct advantages of SAS –





It is possible to intrude mand molars
En masse distalization of mandibular buccal
segments or the entire dentition is possible,
thus reducing t/t time.

SAS might recquire orthodontists to
reconsider their thinking regarding arch
length discrepency, space analysis &
extraction criteria.

58

Conclusions








SAS is a viable modality for distalizing
mandibular molars.
It enables en masse movement with only a
minor surgery to place the anchor plates.
Effective in correcting class III
malocclusions, mand incisor crowding &
dental asymmetries.
Premolar extraction can be avoided.

59


60


61

Eruption of Third Molars :
Relationship to Inclination of
Adjacent Molars


Jackie Badawi Fayad, J C Levy, et al


62

Introduction





Most often impacted
Impaction related to available space –
pterygoid vertical & distal border of first
molar.
Recent studies have questioned
significance of this available space as a
predictor for eruption or impaction.


63

Purpose


To determine the relationship between
maxillary molars’ sagittal inclination and the
eruption of third molars with CT scans


64

Material and Methods




60 subjects ( 30 men, 30 women) with
complete normal permanent dentitions.
2 groups –




First group – 28 subjects, mean age 33.3
yrs, range 16-50 yrs. With erupting or
erupted third molars.
Second group – 32, mean age – 27.6 yrs,
range 16-50 yrs. With impacted right and left
third molars.

65

Material and Methods


Analysis using 2D multiplanar reconstructions


66



Sagittal inclinations of 1st & 2nd molars were
measured by posteroinferior angle formed
by the molar axis ( intercuspid groove bifurcation) and the palatal plane.


67

Results




Rt & Lt 1st & 2nd molars were more mesially
inclined in the group with erupting or
erupted third molars than in the second
group.
Inclination of 1st molar was a predictor of
eruption of 3rd molar.


68


69

Discussion






Sagittal inclination of M1 & M2 was more in
subjects with erupted M3 than in those with
impacted.
Cross sectional study
Effect of age on sagittal inclinations
Measurements on panoramic radiographs not
reliable


70

Conclusions




The vertical position of the 1st maxillary
molar in the sagittal plane is a predictor of
the eruption of the adjacent third molar.
The sagittal inclinations of maxillary molars
increase with age : it could be the effect of
mesial drift.


71

Thank you
Leader in continuing dental education


72

Pendulum Appliance Molar Distalization Efficiency

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