Controversies in orthodontics /certified fixed orthodontic courses by Indian

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Good
Morning

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Controversies
in
Orthodontics

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CONTENTS
 Introduction
 Controversies in Classification of Malocclusion
 Controversies in Diagnosis
a. Diagnostic value of plaster models in contemporary
orthodontics
b. Reliability of Digital vs Conventional cephalometric
Radiology
 Controversies in Etiology of malocclusion
a. Genetic V/s environmental factors.
b. Role of nasal obstruction and tongue thrust.
c. Third molars – a dilemma! Or is it?
 Controversies in Treatment planning
a. Extraction versus Non-extraction.
b. Timing of Orthodontic Treatment

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 Controversies in Treatment modalities
 Orthopedics in orthodontics; fiction or reality
 Controversies in PEA:
- Torque in the Base vs Torque in the Face
- 018” vs 022” slot
- Controversies in Bracket prescription
 Controversies in Orthognathic Surgery
 Root resorption related to orthodontic treatment
 Orthodontic treatment and temporomandibular disorders
 Conclusion and References
CONTENTS

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Introduction
 Controversy – A prolonged argument/
dispute especially when conducted publicly.
 Orthodontics traditionally has been a specialty
in which opinions of leaders were
important, to the point that professional
groups coalesced around a strong leader

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 Angle, Begg, Tweed societies still exist-
―disagreements are then a risk rather than
exception‖.

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 Cults and charismatic leaders have been
more instrumental in establishing our
value systems than has any demonstrated
superiority of one method over another.

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Result
 Thus its more ―Opinion –based‖ rather
than ―evidence – based‖.
 Such science can neither validate the
superiority of a technique nor help to
make rational choices among
alternatives.

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 In time, for most clinicians, practice becomes
routine, standardized and decreasingly
introspective.
 Hence, clinical experience + common sense
assume a more commanding role in
Decision making.

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Controversies
In
Classification of Malocclusion

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Ambiguities of Angle’s classification :
1989 No. 4, 295 - 298Donald J. Rinchuse, Daniel J. Rinchuse.
 In 1900, Edward H. Angle wrote
that all teeth should be
considered when classifying
cases
 In 1907, he emphasized using
the maxillary first molars as
reference teeth.
 Arguments are presented to
illustrate the confusion in relying
solely on Angle‘s system of
classification

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The changes in Angle‘s thinking and writings
between 1900 and 1907 have created a dilemma:
 Should the orthodontist use only the permanent
first molars to determine the classification of an
Malocclusion?
 Or, should the canines be included?
 If so, which teeth, the molars or canines, should
be given priority when determining the
classification of an occlusion?
 Or, should the orthodontist use all the teeth to
assign a case to one of Angle‘s Classifications?

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 The situation arising where one side of a dentition
is in a Class II relation, while the other side is in a
Class III relation, is beyond the parameters of
Angle‘s Classification
 A dilemma could arise when the first molars are in
a Class I relationship and the rest of the dentition
is in a Class II relation.
Ambiguities of Angle’s classification :
1989 No. 4, 295 - 298Donald J. Rinchuse, Daniel J. Rinchuse.

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 What does ―subdivision left‖ describe?
 Some orthodontists believe that it refers to an
asymmetrical occlusion, with a Class II molar
relationship on the patient‘s left side and a Class I
molar relationship on the right side. Other
orthodontists perceive just the opposite.
 As a result, orthodontists in the United States
cannot agree on the meaning of a Class II Division
1 subdivision malocclusion.
A matter of Class: interpreting subdivision in a
malocclusion.
Am J Orthod Dentofacial Orthop. 2002 Dec;122(6):582-6.

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 A survey was sent to the chairperson of each
orthodontic department in teaching facilities in the
United States. Fifty-seven surveys were mailed. The
survey consisted of a 1-page questionnaire that
asked whether, in the orthodontic residency
program‘s philosophy, subdivision refers to the
Class I side or the Class II side.
malocclusion.

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 Thirty-four surveys were returned (return
rate about 60%) with mixed results.
Twenty-two respondents believe that
subdivision refers to the Class II side, 8
believe it refers to the Class I side, and 3
teach their students neither meaning for
subdivision
malocclusion.

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 The premolar classification was put
forth by Morton Katz as a modification
to the Angle‘s classification
 The canine classification

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From the above discussion it is clear that the
system of classification we use today is inadequate in
describing a dental anomaly in it’s entirety, aid in
treatment planning or be easy to use. A universal
classification system will be necessary which will be
accepted by all orthodontists around the world. This
would help us in standardizing malocclusion rather
than disagreeing on the very nature of problem the
patient has.

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Diagnostic value
of plaster models
in
Contemporary
Orthodontics

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 Models are the only three dimensional
records available to represent dentition
in a functional occlusion

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Advantages of Models
 Measurement of dentition and arch length
are easier
 As per ABO study models allow for grading
system evaluating treatment results
 They also serve as a Medico legal record

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Diagnostic value of plaster models in
Contemporary Orthodontics:
Chad Callahan, P. Lionel Sadowsky and Andre Ferreira.
Seminar in Orthodontics 3rd issue 2005
 20 Orthodontic patients( 11 Class I, 7 Class
II, 2 Class III ) were selected
 Four Orthodontists participated with a
experience of 8 to 30 years
 Initially Extra oral photographs, Radiographs
are provided

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 Following which a questionare is given
consisting of 20 diagnostic criteria
including Molar relationship, Canine
relationship, Arch
form, Overbite, Overjet, Crowding etc.

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 Plaster models were later provided and
the Diagnosis and treatment plan were
revisited to evaluate whether models
added any value to the diagnosis

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Results:
 83 Diagnostic values changed of a
possible 1600 i.e, about 95 % of the
Diagnostic values remain unchanged.
 Only 5 out of 20 Diagnostic values were
determined to be statistically significant
include Molar, Canine
relationship, Overjet, Overbite, Depth of
curve of spee.

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Rheude B, Sadowsky Pl, Ferriera A, Jacabson A. An evaluation of
the use of digital study models in orthodontic diagnosis and
treatment planning Angle Ortghod 75: 292-296, 2005
 They compared
Digital models to
plaster models
 They found 14 out
of 20 diagnostic
criteria showed
variation
 They concluded this
variation as clinically
insignificant

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Han U. Consistency of orthodontic
treatment decisions relative to
diagnostic records
AJO DO 1991, 100: 212-219
 In contrast to previous studies, Diagnostic
models could provide adequate amount of
information for treatment planning in 55%
of cases

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Current view point
 Diagnostic changes made following the
addition of study models to the other records
proved not to be clinically significant.
Plaster models are
currently being
replaced by digital
models and have
been proven to be
excellent alternative

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Reliability of
Digital
vs
Conventional
cephalometric
Radiology

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 Cephalometrics
remains the only
practical quantitative
method that permits
investigation and
examination of the
spatial relationships
between both
cranial and dental
structures

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Advantages of Digital Cephalometrics
 Instantaneous image
acquisition
 Reduction of radiation
dose
 Facilitated image
enhancement and
archiving
 Elimination of technique
sensitive developing
process and its costs
 Facilitated image
sharing www.indiandentalacademy.com

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Reliability of Digital vs Conventional
cephalometric Radiology: A comparative
evaluation of landmark identification error.
Scott R. Mclure etal Seminar in Orthodontics 3rd Issue 2005.
 Purpose: The accuracy of landmark
identification utilizing these two different
image acquisition methods should be
compared
 19 commonly used cephalometric landmarks
are used in the analysis

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Method
 The landmarks location on the digital images
and transparent acetate films could then be
described by using X and Y co-ordinates with
the aid of computerized program
 The average position for each landmark was
also used to facilitate accurate superimposition
in the creation of scatterograms for each
landmark.

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Results:
1. Three of the 19 landmarks indicated statistically
significantly higher landmark identification error
for film based identification methods than for
digital image based identification
2. But the error is less than 1 mm indicating
unlikely clinical significance.

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Trpkova etal
 Conducted similar study in 15 skeletal
landmarks
 Concluded Landmark identification using
digital images had more precision in both x
and y dimensions than conventional film
based landmark identification.

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Current view point
 The advantages of digital cephalometry
coupled with proven clinical performance
equal to that of film may lead to shift in
what is considered the standard for
cephalometric radiography in future.

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ETIOLOGY
OF
MALOCCLUSION

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 A strong influence of
inheritance on facial
features is obvious
to recognize.
 It is also apparent
that certain types of
malocclusion run in
families.
e.g. Hapsburg jaw

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Malocclusion could be produced by inherited
characteristics in two possible ways:
 Inherited disproportion between the size of
teeth and that of the jaws-producing
crowding/spacing.
 Inherited disproportion between size/shape of
upper and lower jaws –producing improper
occlusal relations.

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 There is considerable
anthropological evidence that
population groups that are
genetically homogenous tend
to have a normal occlusion
e.g: Melanesians of Philippine
islands, this is the result of
genetic isolation and
uniformity.

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 Based on this
evidence, workers of the
yesteryears were tempted to
conclude that the great
increase in population and its
mobilization was the primary
explanation for the increase
in malocclusion in modern
man
 They blamed this on the improper function
of jaws under degenerate modern conditionswww.indiandentalacademy.com

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The earlier part of the 20th century
Development of classical Mendelian
genetics.
 The new view was that malocclusion is
primarily the result of inherited dento-facial
disproportions strengthened by the breeding
experiments carried out by Prof. Stockhard
(1930).

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Later part of 20th century
 A revival and a swing back to the earlier
concept that jaw function is related to
malocclusion.

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 A number of familial and twin studies in the latter
part of the century by workers like Lundstrom
(1984), Corrucini (1980), Potter (1986), Bolton and
Brush, Harris and Johnson (1991) gave a more
balanced view showing that there is no single
explanation for malocclusion in terms of
function, heredity or environment, but is a result of
a complex interplay of these elements.
Current view point:

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RESPIRATORY PATTERN
 Respiration is the Primary determinant
of jaw and tongue posture.
 Altered respiratory pattern  change
posture of head, jaw, and tongue 
alters equilibrium  jaw growth and
tooth position affected.

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Harvold, Tomer and Vargevik (1981)
 Total nasal obstruction in monkeys, for a
prolonged time led to the development of
malocclusion.
 Placing a block on the roof of the
mouth, forcing the tongue to a more
downward position, producing a variety of
malocclusion.

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 Because total nasal obstruction in
humans is so rare, the important
question is whether partial nasal-
obstruction is a risk factor in causing
malocclusion ?
 Does nasal obstruction equates  mouth
breathing + lip-apart posture ?

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Ballard and
Gwynne-Evans (1958)
 Nose breathers, who have a lip - apart
posture, usually have post seal with
tongue against soft palate as an
adaptive mechanism.

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Wood side, Linder, Aronson,
Lundstrom (1991)
Concluded that change from mouth-open to mouth-
closed breathing after adenoidectomy for severe
nasopharyngeal obstruction in 38 children
 Greater mandibular growth expressed at chin in
both sexes:
3.8mm in males & 2.5mm in girls
 Greater facial growth expressed at
midface, only in males.
 No change in maxillary growth direction.

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Bushey
 Found no relationship between nasal
respiration and linear measurements of
adenoids in lateral cephalogram before and
after adenoidectomy.

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Fields et al (1991)
 Compared respiratory mode in normal and long-
faced subjects.
 Results:
Long-faced  significantly smaller component of
nasal air flow (40%) but total volume and nasal
cross-sectional area were similar.
 He concluded that Significant difference in airway
impairment does not have direct effect on
breathing mode  behaviorally determined than
structurally dependent.

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RME and Nasal obstruction
 RME for transverse maxillary deficiency correction also
increases nasal airflow.
 Hartgerick et al (1987)
-No increase in % of nasal breathing.
-Can decrease in nasal resistance.
-Did not change respiratory mode of
the patient

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Bell (1977) and
Spalding et al (1991):
 No decreased nasal resistance and no
increased % of nasal airflow.
 Provides another example why clinicians
and researchers should not assume that
because one of the parameters of nasal
respiraton is affected, others like cross-
sectional area, peak nasal flow rate and
respiratory mode will all be similarly
affected‖.

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Contemporary view
 2 opposing principles, leaving large gray area
between them:
1. Total nasal obstruction likely to alter pattern of
growth and lead to malocclusion. – High
percentage of oral respiratory is over
represented in long-face population.
2. Majority of individuals with long-face deformity
have no evidence of nasal obstruction because
some other etiological factor as principal cause.

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More recent findings suggest that
nasal-oral breathing per se is not
necessarily harmful to cranio facial
growth. However, in instances where
the naso-pharyngeal or oro-
pharyngeal air space is small,
exaggerated postural responses in
obligatory mouth breathers may be
detrimental to craniofacial growth.

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Tongue-thrust as etiologic factor
 Definition- placement of
tongue-tip forward
between incisors during
swallowing.

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 The term tongue-thrust is a
misnomer, since it implies that
the tongue is forcefully thrust
forward.
 Laboratory studies indicate
that individuals who place the
tongue tip forward when they
swallow do not have more
tongue force against teeth
than those who keep tongue
tip back- in fact, tongue force
may be lower. – Profitt (1972)www.indiandentalacademy.com

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 The term tongue-thrust is a
misnomer, since it implies that
the tongue is forcefully thrust
forward.
 Laboratory studies indicate
that individuals who place the
tongue tip forward when they
swallow do not have more
tongue force against teeth
than those who keep tongue
tip back- in fact, tongue force
may be lower. – Profitt (1972)www.indiandentalacademy.com

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 Tempting to blame tongue-thrust as a cause
for open bite, since these individuals keep
their tongue between the anterior teeth when
they swallow.
 The mature/ adult swallow pattern appears in
some normal children as early as age 3, but
not present in majority until about age 6 & is
never achieved in 10 - 15% of a typical
population

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 Some times children & adults who
place their tongue between anterior
teeth are spoken of as having a
retained infantile swallow- this is clearly
incorrect, since only brain damaged
children retain a truly infantile swallow
in which posterior part of the tongue
has little or no role. (Profitt)

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 Equilibrium theory: Light but
sustained pressure by tongue against
the teeth would be expected to have
significant effect. Tongue-thrust
swallowing simply has too short a
duration to have an impact on tooth
position.

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 Tongue pressure against the teeth
during a typical swallow is < 1 seconds.
A typical individual swallows about 800
times in a day, while awake, but has
only a few swallows / hour while
asleep. Hence – total/ day is < 1000
times, & thus 1000 seconds of pressure
has little/no effect.

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Current view point:
Tongue –thrust is primarily seen in 2
circumstances:
 In young children with normal occlusion
– transitional stage in normal physiologic
maturation.
 In individuals of any age with displaced
anterior teeth – adaptive.

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Current view point:
 Hence it is more a ―Result‖ than a ―cause‖
 However tongue posture is more important.
 Light pressure for more duration  change in
tooth position.

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THIRD MOLARS – A DILEMMA!
OR IS IT?
 Third molars are usually
considered as Vestigial
organs which may be
reserves for mutilated
dentition.
 The role that mandibular
third molars play in lower
anterior crowding has
provoked much speculation
in the dental literature.

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 In a survey of more than 600
orthodontists and 700 oral surgeons,
Laskin found, that 65% were of the
opinion that third molars sometimes
produce crowding of the mandibular
anterior teeth.
 As a result of such opinions, the
removal versus the preservation of third
molars became the subject of
contention in dental circles.www.indiandentalacademy.com

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The differing views
 Third molars should be removed even on a
prophylactic basis, because they are frequently
associated with future orthodontic and
periodontal complications as well as other
pathologic conditions.
 There is no scientific evidence of a cause and
effect relationship between the presence of third
molars and orthodontic and periodontal
problems.

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―Pressure from behind‖
theory:
 The late lower arch crowding is caused by
pressure from the back of the arch.
But whether this pressure results from:
1. Dev. 3rd molar.
2. Physiologic mesial movement / drift.
3. Anterior component of force derived
from forces of occlusion on mesially
inclined teeth.
Is not sure

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Relationship between 3rd molars and
incisor crowding
 Bishara et al (1989 and 1996) reviewed
changes in Lower incisor that occur with time
in untreated populations between 12 and
25 years and again at 45 years
 Increase in tooth size arch length discrepancy
with age – consistent decrease in arch length.
 Average changes 2.7mm in males; 3.5mm in
females. These changes were attributed to a
consistent decrease in arch length that
occurred with age.

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 Fastlicht (1970) found that in
orthodontically treated subjects- 11% had
3rd molars, but 86% had crowding.
 Little et al (1981) observed that 90% of
extraction cases that were well treated
orthodontically ended up with an
unacceptable lower incisor crowding.
Orthodontic treatment patients

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 These long term studies indicated that
the incidence as well as the severity of
mandibular incisor crowding increased
during adolescents and adulthood in
both the normal untreated individuals
as well as orthodontic treated
patients, after all retention is
discontinued.

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Studies relating 3rd molar to crowding of
dentition:
 Bergstrom and Jensen (1961)
Cross-sectional study examined 30 dental
students of whom had unilateral agenesis of
upper 3rd molar and 27 had agenesis of one
lower 3rd molar.
 More crowding in the quadrant with 3rd molar present
than in the quadrant with the third molar missing.
 Mesial displacement of lateral dental segments on the
side with 3rd molar present in the mandibular arch
not in the maxillary arch.
 The unilateral presence of a third molar did not have
an effect on the midline.

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Schwarze (1975)
 Compared a group of 56 patients with
third molar germectomy to 49 subjects
with third molars. He found
significantly greater forward movement
of first molars associated with
increased lower arch crowding in the
non extraction group.

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Lindquist and Thilander (1982)
 Extracted third molar unilaterally in 52
patients and found more stable space
conditions (less increase in crowding)
on the extraction side compared with
the control side in 70% of cases.

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Studies indicating lack of
correlation between
mandibular 3rd molar and
post retention crowding

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Retrospective studies
 Kaplan (1974) :.
The sample consisted of 75 orthodontically
treated patients on whom pretreatment, post
treatment and 10 years post treatment study
models and lateral cephalograms were
obtained.
-Mandibular third molars and post retention crowding Kaplan R.
AJO DO 1974 ;66:411-430

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 The sample was divided into three groups:
 The first group consisted of 30 persons with both
third molars erupted to the occlusal plane, in good
alignment buccolingually, and of normal size and
form.
 The second group consisted of 20 persons with
bilaterally impacted third molars. All patients in this
group were candidates for surgical removal of the
third molars on the basis of postretention periapical
radiographs.
 The third group consisted of 25 patients with bilateral
agenesis of the mandibular third molars.

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 Presence of 3rd molar does not produce
a greater degree of lower anterior
crowding or rotational relapse after
cessation of retention.

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Ades et al (1990)
 in a cephalometric study on a similar
sample found :
 No significant differences in mandibular growth
patterns between various 3rd molar groups –
erupted, impacted or agenesis.
 Majority of cases have incisal crowding, but no
correlation with 3rd molars.

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 Although the mandibular third molar
probably does exert an insignificant
force on the dental arch during its
eruption, an objective review of the
existing information regarding this topic
must conclude that the third molars do
not significantly influence the lower
anterior crowding.
Current view point

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EXTRACTION
vs
NON-EXTRACTION
The only life and
death
situation in
orthodontics
is whether to
Extract

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―To extract or not to extract‖
was one of the early debates
that clouded orthodontic world
ever since its beginning.

86
2 main reasons for extraction:
 Provide space to align remaining teeth
in crowding.
 Allow teeth to move for camouflaging
skeletal malocclusion- Cl-II/Cl-III

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Late 1800
 Late 1800 saw a casual attitude
towards extraction

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Angle proposed 2 key
concepts:
 Skeletal growth 
Influenced readily by
external forces.
 Proper function of
dentition would be the key
for maintaining teeth in
their correct position.
Early 1920’s
For him ―relapse‖ meant – adequate occlusion not reached.

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―If correct occlusion is produced
then result is stable, if result is
not stable it was the fault of
orthodontist and not the theory‖.

90
Angle‘s proposal and Beliefs
 Ideal facial esthetics would result when
the teeth are placed in ideal occlusion.
 He believed this can be achieved when
the dental arches are expanded so that
all the teeth were in ideal occlusion.

91
Calvin Case
 Argued that although
the arches could always
be expanded so that the
teeth could be placed in
alignment, neither
esthetics nor stability
would be satisfactory in
the long term for many
patients

92
Dewey vs Case
 The controversy culminated in a widely
publicized debate between Angle‘s
student Dewey and Case in the dental
literature of 1920‘s.
- The Extraction debate of 1911 by case, Dewey and cryer.
Discussion of case: The question of extraction in
orthodontia. AJO 50: 751,1964www.indiandentalacademy.com

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 Angle followers won : Extraction
disappeared between World War I & II.
 Even in South America, where removable
(Crozat) or twin wire appliances were
used  accepted non –extraction and its
philosophy under pinning.

94
From 1930’s – 1970’s
 Charles Tweed
re-treated the relapse cases
with extraction; previously
treated with non-extraction
methodology, & found
occlusion to be much more
stable.
 He supported his theory by
Cephalometrics

95
late 1940‘s
 Extraction reintroduced widely
 Raymond Begg popularized
―Begg‖ appliance for
extraction treatment.
 This was further strengthened
by Prof. Stockard‘s
experiments which showed
that malocclusion could be
inherited

96
So why the total change in
philosophy?
 Instability of non extraction results due
to Arch length collapse in particulary
1. Lower anterior crowding
2. Reversion to original class II
malocclusions and procumbencies.

97
Between 1970-1990’s:
 Saw the revival of non-extraction philosophy.
 Premolar extraction does not guarantee stability of tooth
alignment.
Little, Wallen and Riedel – 1981 AJO.
MC Reynolds and Little – 1991 Angle Orthod
 Lower anterior crowding recurred post retention
 Deep bites recurred more readily in all 4 extraction cases

98
Argument resurfaces
“If result not stable either way,
why sacrifice teeth at all”.
vs
“If extraction cases are unstable,
non-extraction would be worse”

99
 Changing views of esthetics : Fuller
profile than orthodontic profile
 Change from banding to bonding and
introduction of functional appliances.

100
 The ill-famous litigation – Witzig and
Spahl (1980)
Premolar extraction causes distalization
of mandible posteriorly, displacement of
condyle resulted in perforation of
articular disc  TMD.

101
What happened? Why this shift back to
an approach to treatment which was
discarded 50 years ago?
 Management of Non extraction treatment has
improved
1. Issue of growth and our ability to
influence it
2. Reduction of caries maintaining
arch length.
(Mixed dentition treatment)
3. Reduced camouflage treatment

102
Treatment modalities converting
borderline cases into non –extraction
cases:
 Early intervention:
 Use of ‗E‘ space.
 Proximal stripping of primary teeth.
 Space regainers with space maintainers.
 Arch expansion.
 Use of functional appliances.
 Molar distalization.
 Bonded attachments rather than banded
ones.

103
Treatment modalities converting
borderline cases into non - extraction
cases:
 Adult:
 Molar distalization.
 Inter-proximal reduction.
 Arch expansion.
 Surgery for skeletal discrepancies.

104
Expansion vs Extraction
 Acceptable range of
protrusion in biologic limits
– expand.
 Control space closure by
combination of retraction
(anteriors) and protraction
(posteriors) – extract.

105
Importance of soft tissue
 Lip separation – increases with tooth
prominence.
 Thick, full lips – can afford prominent
incisors.
 Cephalometric readings can serve as
guidelines.
 Size of nose and chin.
 Lip strain i.e. lack of well defined
labiomental sulcus.

106
Stability considerations
 Limiting forces from cheeks
 Fenestrations in Buccal cortical plate
(> 3mm)

107
Beauty lies in the eyes
of the beholder and
in the face of the beheld
But who is the better
judge of the beauty?

108
Saint Louis university,
 63 Border line Extraction and Non
extraction patients selected by
discriminate analysis
 Patients evaluated own pre and post
frontal photographs 14 years post
treatment
Paquette etal 1991, Johnson etal 1994

109
 57% of Non - Extraction patients
thought orthodontic treatment
improved Frontal Facial appearance
 69% of Extraction patients thought the
same
Saint Louis university,

110
Luppanapornlap and
Johnson, AO 1993
Mean start, finish and recall facial Polygons for the extreme extraction and
non extraction samples. At recall, it was the non extraction subjects
Who tended to have the “flatter” profilewww.indiandentalacademy.com

111
 Witzig and Spahl 1987 and Dierkes 1987
have asked
“What are the spaces at the corners of
smile from extraction treatment?”

112
Washington university
 Sample of 60 Extraction and Non
extraction patients
 Panel of 10 lay persons
 Evaluation of post treatment smile
photograhs
- Johnson and smith 1990

113
Washington university
 No predictible relationship between
extraction of premolars and Esthetics of
smile
- Johnson and smith 1990

114
 If the inter canine width or arch form is
maintained during treatment, whether
extraction or non extraction, the width
of the smile would be the same post
treatment

115
The effects of buccal corridor spaces and arch form on smile esthetics
Roden-Johson D., Gallerano R, English J AJODFO 2005, 127: 343-50
• 60 Dentists, orthodontists, and lay persons
evaluated photos of patients with buccal
corridor spaces and those without
• No difference in smile scores related to
Buccal corridor Spaces
• Lay person have no preference for arch form
• Dentists & Orthodontists like broader arch
forms www.indiandentalacademy.com

116
 The claim that the
Negative spaces in
the Buccal corridor
are a routine result
of extraction
treatment appears
to be false.
Miss world 2002
Azra akinwww.indiandentalacademy.com

118
Contemporary Extraction
Guidelines:
For Class I crowding / protrusion:
 Arch length discrepancy < 4mm with no vertical
discrepancy: non-extraction.
 Arch length discrepancy = 5-9mm
Non-extraction : Transverse expansion of
premolar segment.
Extraction : Any pattern of extraction
depending on hard and soft tissues.
 Arch length discrepancy > 10mm :Extraction

119
Lower lip to E- plane (Caucasians)
Bowman and Johnston AJO DO 2000www.indiandentalacademy.com

120
Current view point
 We find that we have completed the
circle and rather than anterior crowding
being the principal reason for extraction
treatment, facial cosmetics should
assume the major diagnostic role in
border line cases.

121
Earlier treatment of maxillo-mandibular basal
discrepancies by old and new treatment philosophies
and mechanics have produced more stable non-
extraction corrections. Better control of Lee-way space
and a reduction in caries has helped reduce the
amount of lower anterior flaring that was seen in non-
extraction cases in the first third of the century. These
reasons have moved the specialty of orthodontics to a
mixed but more non-extraction oriented approach to
treatment.

122
EARLY
VS
LATE
TREATMENT

123
 The optimal timing of treatment of children
with malocclusion remains controversial.
 Determining the relative merits of alternative
treatments is complex, not only because of
variability in initial conditions and treatment
response, also because of differences
between orthodontists in treatment
beliefs, goals techniques and even skills.

124
Early treatment
 Treatment started either in primary or
mixed dentition that is performed to
enhance the dental and skeletal
development before the eruption of the
permanent dentition.

125
Goals and benefits of phase I
treatment
1. Superior facial esthetics
2. Greater ability to modify the growth process
3. Fewer extractions
4. Reduction in the duration and difficulty of subsequent therapy
5. Consistent and predictable elimination of phase II treatment
6. Improvement in patients self concept
7. Reduction in the fracture potential of protruding maxillary
incisors
8. Greater patient compliance
9. Eliminate, if not reduce the need for future jaw surgery
10.Greater stability

126
Iatrogenic damages of early
treatment
1. Longer overall treatment time
2. Loss of compliance
3. Greater risk due to prolonged treatment such
as root resorption, whilespot lesion, bone loss
caries
4. Increased cost
5. Dilacerations of roots
6. Impaction of maxillary canines by premature
uprighting of the rootsof lateral incisors
7. Impaction of maxillary second molars

127
The procedures in
phase I treatment are
1. Growth modification
a. Headgears
b. Functional appliances
c. Face mask
d. Chin cap
2. Arch length discrepancy
a. Serial extraction
b. Arch expansion
c. Preservation of arch length
3. Open bite correction
4. Correction of tooth eruption disturbances

128
Timing of Cl-III treatment
Timing of chin cup treatment for Class III- irrelevant
for growth modification & stability.
Semin Orthod 3:224-254;1997.
Face mask treatment for Class III with maxillary
deficiency is evidence based.
AJODO 113:333-343;1998.
Semin Orthod 11:112–118 ;2005

129
Treatment of slow or non-growing
patients during late adolescent or
adulthood respectively depends upon
growth status, esthetics & severity of
Malocclusion.
Decide
Camouflage Orthognathic
Surgery
Semin Orthod 11:112–118 ;2005

130
Timing Of Cl II Treatment
Early intervention for growth modification-
Limited skeletal changes reported in long
term evaluation.
Slow or non-growing patients during late
adolescent or adulthood respectively-
Camouflage treatment.
Acceptable results at long term follow up.
AJODO 123:266-278;2003.
Semin Orthod 11:112–118 ;2005

131
Late adolescence & adults with severe
skeletal Class II- Orthognathic surgery
Semin Orthod 11:112–118 ;2005

132
1. When skeletal change is a goal of Class II malocclusion
treatment by growth modification or surgery, dental
compensation is a key component to the success of
treatment.
2. The timing of treatment was largely determined by the
severity of the malocclusion and the maturation of the
patient. The era of skeletal correction of malocclusion
with growth modification and innovative surgical techniques
also emphasizes dentoalveolar changes are the
ultimate solution for many Class II malocclusions.
Semin Orthod 11:112–118 ;2005

133
Melsen (AJO-2003)
 She did a long term study on
intermaxillary molar displacement. The
first time in the year 1978 and then
again 7 years later with patients treated
with the Kloehn headgear along with
cervical traction.
 A strong tendency of the molars to
return to the class II relationship was
demonstrated.www.indiandentalacademy.com

134
Melsen (AJO-2003)
 No evidence that a Class I relationship obtained by
extraoral traction was more stable that that obtained
by functional or intermaxillary appliances.
 It was noted, however, that the variation in the
vertical development was related more to each
patient‘s growth pattern than to the force system
applied.
 After cessation of the headgear, intramaxillary
displacement of the molars was noted, and the total
displacement of the molars did not differ from that of
the untreated group.

135
Functional appliances
 For 30 years, investigators have noted
facial skeletal changes in monkeys as a
result of altered oral function.
 The potential for changes both as a
result of increased mandibular length
and also effective mandibular position
by means of temporo-mandibular joint
remodeling was proposed.

136
Florida study (AJO DO-1998)
Keeling,
 Children aged 9 years at the start of
treatment were randomly assigned to
control, Bionator and Headgear with
Biteplates.
 There was no significant differences in the
final PAR scores when patients who wore
their headgear or bionator as a retention
appliance between phase 1 and phase 2
treatment were compared with patients who
did not wear any appliance during this period

137
University of North Carolina
(AJODO 1997)
PHASE I Randomized
Observation Functional Appliances Headgear
End of Phase I in 15
months
Retention Phase for 1 year
Assigned to four different
orthodontists for phase II

138
 It was a prospective long term study.
 It had an almost ideal research design.
 Conducted by Drs. Camilla Tulloch and
William Proffit
 All subjects were children with overjet
of 7mm
University of North Carolina
(AJODO 1997)

139
University of North
Carolina(1997-2004) Results
 There was no difference between the
groups with regard to ANB angle either
at the start or after phase II of
treatment.
 No difference in the quality of dental
occlusion between the children who had
early treatment and those who did not.
 There was approximately the same
distribution of success and failure with
and without early treatment.www.indiandentalacademy.com

140
University of North
Carolina(AJODO 1997) Results
 Early treatment did not reduce the
number of children needing extraction
of premolars or other teeth during
phase II of treatment.
 Early treatment did not reduce the
eventual need for orthognathic surgery.
 There was little influence on the time
duration that both groups spent
wearing fixed appliances.www.indiandentalacademy.com

141
University of North
Carolina(AJODO 1997) Results
 Early treatment did reduce severity of
class II malocclusion.
 Overjet did decrease in the treated
groups whether the appliance was a
headgear restricting the maxilla or a
functional one positioning the mandible
forward.
 Still doubt whether early treatment is
better or not as long as treatment is
provided at some point in time.

142
Studies on Arch length discrepancy
(Little AJO 2002).
 Without treatment a short arch length
will only get worse.
 Cases that underwent expansion
showed the poorest long-term results
 Serial extraction followed by routine
treatment yields no greater long-term
improvement over premolar extraction
in the full dentition.

143
Two-stage treatment: an outcomes-based assessment
Gianelly A.A. Progress in Orthodontics, Volume 1, Number 1, 1
January 2000, pp. 3-9(7)
 Neither self-concept nor the ability to modify
growth is improved by stage-one treatment,
 There are no skeletodental differences
between the results obtained by one-stage
and two-stage treatments.
 Accordingly, two-stage treatment cannot be
endorsed on the basis of providing unique
and characteristic psychological or
skeletodental benefits.

144
Assessment of Orthodontic Treatment Outcomes: Early Treatment
versus Late Treatment: Tsung-Ju Hsieh, Yuliya Pinskaya, W. Eugene
Roberts, The Angle Orthodontist: Vol. 75, No. 2, pp. 162–170
 Comparison of the final results between early
vs late-treatment groups showed that the
early-treatment group had significantly longer
treatment time and worse CCA scores than
the late-treatment group.
 There was no significant difference between
early- and late-treatment groups regarding
the ABO OGS score.

145
Current view point
 There is very little evidence in the literature
to suggest the two phase treatment can
significantly modify growth or eliminate the
need for protracted phase two treatment nor
can it be justified to result is fewer
extractions or avoidance of orthognathic
surgery.
 Early phase one treatment is beneficial in
reducing the incidence of incisors trauma and
may be useful in correction of eruption
disturbances.

146
Thank you

147
Orthopedics
in
Orthodontics
fiction or
reality?

148
 Duterloo defines orthopedic effect in
orthodontics as a change in the position of
bones in the skull in relation to each other
induced by therapy
 According to Isaacson, orthopedic
appliances provide a new muscular and
functional environment for the facial bones
that encourages growth changes of either the
mandible or the maxilla.

149
Class III Orthopedic changes
 Stimulation of maxillary growth in all
cases, inhibition of mandibular
growth as a result of class III
therapy was reported in 67% of the
studies
Orthopedics in orthodontics: Fiction or reality. A
review of the literature—Part II AJO-DO Volume 1996
Dec (667 - 671)

150
chincup therapy
 Few studies report on long-term effects of
chincup therapy. The findings of Sugawara et
al. indicate that chincup therapy did not
necessarily guarantee positive correction of
the skeletal profile after complete growth.
Sugawara J, Asano T, Endo N, Mitani H. Long-term
effects of chincap therapy on skeletal profile in
mandibular prognathism. Am J Orthod Dentofac
Orthop 1990;98:127-33.

151
 Therapeutic maxillary expansion
ranging from 0.9 to 3.2mm in 12 weeks
to 6 months (short treatment period).
Wertz R, Dreskin M. Minor palatal suture opening: a
nonnative study. Am J Orthod 1977;71:367-89.
Maxillary Expansion

152
Normal Maxillary growth
 According to Bolton studies the yearly
increase in interjugular width is
approximately 1mm, which coincides
with Rocky Mountain Standards

153
Normal Maxillary growth
 Savara claims that the maxillary
width, expressed as distance between
both pterygomaxillary
fissures, increased with 0.18mm
between 12 and 16 years, because of
normal growth.
 Savara BS, Singh U. Norms of size and annual increments of
seven anatomical measures of maxillae in boys from three to
sixteen years of age. Angle Orthod 1968;38:104-68.www.indiandentalacademy.com

154
 Therapeutically induced maxillary expansion
is larger than the increase expected because
of normal growth, within a short observation
period.
 As stated by Sarnäs, the net increase out of
retention is only 1.6 mm being within
anticipated normal growth.
 Sarnäs KV, Björk A, Rune B. Long-term effect of rapid maxillary
expansion studied in one patient with the aid of metallic Implants and
roentgen stereometry. Eur J Orthod 1992;14:427-32.

155
 No scientific evidence exists so far to
indicate that an orthodontist can induce
a stable enlargement of maxillary basal
bone that exceeds normal growth.
Current view point in Maxillary
Expansion

156
Bite Opening controversy
 Although the sagittal construction bite
advancement concept generally was accepted
by clinicians in Europe (it varied from 3 to 6
mm) depending on the severity of
anteroposterior dysplasia and resultant
abnormal buccal segment interdigitation, the
theory pertaining to the amount of vertical
opening and its effects on the muscles
produced considerable controversy.

157
 Anderson and Haupl’s interpretation
presupposed freedom for the mandible
to assume the physiologic rest position

158
 Slagsvold, later professor of
orthodontia at Oslo, reported that his
own observations did not substantiate
this premise completely. Nevertheless
he concurred that forward posturing
should not exceed the rest position
vertical opening of 2 – 4 mm.

159
 Too wide on opening made compliance
more difficult and could produce a
depressing force on the teeth, hardly
desirable in deep bite, class II
malocclusions.
 Grude and Frankel strongly support this
construction bite limit

160
 The philosophy of Harvold & Woodside
has been to exceed the free way space
limits, if for no other reasons than to
keep the appliance in place at night
during sleep or as to maintain a
corrective stimulus.

161
Incremental vs one step
advancement
Frankel recommends incremental small
advancements of 2 to 3 mm for his appliances rather
than the great leap forward of 5 to 7mm.
Reactivation of optimal tissue response as well as
enhanced patient compliance are factors. This
concept encourages daytime wear. The frequency of
deglutition is increased and phasic muscle activity is
enhanced.
Frankel R: Clinical relevance of step by step
mandibular advancement in the treatment of
mandibular retrusion using the frankel appliance AJO
1996 333, 1989

162
Sander and Schmuth also have studied the
effect of large protrusion construction bites
with tendency to disclude the appliance both
during the day and at night reducing the
desired effect and jiggling selective teeth.
Milestones in the development and practical application of
functional appliances
AJO 1984: 48, 1983
advancement

163
 Also histological evidence support periodic
incremental advancement because of the
periodically enhanced condylar and fossa
response with each adjustment
 With single 6 to 7 mm the condylar and fossa
growth stimulus is of shorter duration,
daytime wear becomes more difficult and
adverse labial proclination of mandibular
incisors may be greater.
advancement

164
Day time vs Night time wear
 Selmer Olsen believed
that the muscles could not
actually be stimulated
during sleep. Nature had
designed them to rest at
night and swallowing
occurred only 4 to 8 times
any hour
 Komposch and Hackenjos, Sander,
Schmuth, Herren corroborated the finding that
activator does not activate muscles during
sleep.

165
 Harvold and Woodside, Ricketts
recommend nighttime wear of appliance
for maximum effect.
Day time vs Night time wear

166
Effect of head posture during sleep
 Mandibular rest position depends on the head
and body posture, thereby the restriction of
muscle movement required to create the
desired mandibular position change, without
the activator in place, varies constantly
involving different muscle groups and
creating different force vectors on the
activator.
 Variation in head posture during sleep alters
the magnitude and direction of force.

167
 The phase of sleep, intraoral air
pressure, dream cycle, state of mind
are additional conditioning factors all
uncontrolled by clinician.
 Only the mandibular position and the
potential effect on glenoid fossa are
controlled.
Effect of head posture during sleep

168
What happens with the use of functional
appliances?
 In spite of considerable research and debate
the precise mode of action of functional
appliance remains obscure
 Dentoalveolar changes: Harvold and
others have stressed the importance of a
vertical manipulation of the functional
occlusal plane in achieving class II corrections
with removable functional appliances.
-

169
Dentoalveolar changes
 Prevention of the eruption of maxillary
buccal segments which is normally in
downward and mesial direction
 Removable functional appliance do not
distalize the upper dentition unless
Headgear is used

170
 Midface restriction
 Effect on Mandibular growth: is
again a controversy
What happens with the use of functional
appliances?

171
Can we grow smaller Mandibles?
 Much of the work demonstrating the
ability of functional appliances to
stimulate mandibular, growth as based
on animal experimentation.

172
Animal studies
 Cartilage proliferation by increased mitotic activity in pre-
chondroblastic zone  growth increments of condyle.
Petrovic A, Stutzmann J, Oudet CL. Control processes in the postnatal
growth of the condylar cartilage of the mandible. In: McNamara Jr
JA, ed. Determants of mandibular form and growth. Monograph 4,
Craniofacial Growth Series. Ann Arbor: Center for Human Growth and
Development, University of Michigan, 1975.
 Increase in effective length of mandible
McNamara Jr JA, Bryan FA. Long-term mandibular adaptations
to protrusive function: an experimental study in Macaca
mulatta. Am J Orthod Dentofac Orthop 1987;92:98-108.

173
 Therapeutic remodeling of glenoid fossa
Woodside DG, Metaxas A, Altuna G. The influence of
functional appliance therapy on glenoid fossa
remodeling. Am J Orthod 1987;92:181-98.
 Catch-up growth after treatment independent of
direction of therapeutic force.
Elder JR, Tuenge RH. Cephalometric and histologic
changes produced by extraoral high-pull traction to
the maxilla in Macaca mulatta. Am J Orthod
1974;66:599-644.

174
 Several investigators showed dramatic changes
in mid-face of monkeys after headgear
treatment.
Henry HL, Cleall JF. Radiographic cephalometric method of assessment of
craniofacial growth in monkeys. J Dent Res 1974;53:369-74.
Joho JP. The effects of extraoral low-pull traction to the mandibular dentition of
Macaca mulatta. Am J Orthod 1973;64:555-77.
Meldrum RJ. Alterations in the upper facial growth of Macaca mulatta resulting from
high-pull headgear. Am J Orthod 1975;67:393-411.
Animal studies

175
 The same story holds true for maxillary protraction
studies on monkeys.
Kambara T. Dentofacial changes produced by extraoral
forward force in the Macaca irus. Am J Orthod
1977;71:249-77.
 Experiments on mandibular retrusion in rats show
histological and some macroscopic decrease of
mandibular length.
Charlier et al (1969),Petrovic et al (1975),Janzon and Bluher (1965),Ajano
(1986)
Animal studies

176
 Whether these findings on animal models are
applicable to human beings during routine clinical
treatment is debatable.
 Discrepancies between animal and human studies are
expected since animal experimentation frequently
involves the use of continuous forces.
 These types of forces usually are impractical and
often undesirable in most clinical situations therefore
treatment results can be expected to be less dramatic
and more variable

177
Long-term Effect After Activator, Headgear-
Activator, Herbst Appliance and Headgear
Treatment
 The orthopedic effect induced by an appliance is one
point of interest, but more interesting is long-term
behaviour
 Panchez et al published many reports on long-term
effects on Herbst appliance.
 Only temporary effect on existing skeleto-facial growth pattern.
 After orthopedic intervention – maxillary and mandibular
growth seemed to strive to catch up with early pattern.
Pancherz H, Anchus-Pancherz M. The headgear effect of the
Herbst appliance: a cephalometric long-term study Am J Orthod
Dentofac Orthop 1993;103:510-20.

178
 Basal maxillary changes are relatively
stable 6 years after retention. The
growth pattern of the maxilla was
changed in a more posterior-inferior
direction
Wieslander L, Buck DL. Physiologic recovery after
cervical traction therapy. Am J Orthod 1974;66:294-
301.
Long-term Effect After Activator, Headgear-
Activator, Herbst Appliance and Headgear Treatment

179
 Recently, DeVincenzo investigated changes in
mandibular length before, during, and after
successful orthopedic correction of Class II
malocclusions. The increase in mandibular
length during the functional appliance phase
was pronounced and the rate of increase is
dramatic.
DeVicenzo JP. Changes in mandibular length before, during,
and after successful orthopedic correction of Class II
malocclusions using a functional appliance. Am J Orthod
Dentofac Orthop 1991;99:241-51.

180
J Orofac Orthop. 2001 Nov;62(6):436-50.
Clinical application and effects of the Forsus spring. A study of a new Herbst
hybrid.Heinig N, Goz G.
Evaluation of the lateral cephalograms showed that dental effects
accounted for 66% of the sagittal correction. The sagittal occlusal
relations were improved by approximately 3/4 of a cusp width to the
mesial on both the right and left side as a result of distal movement of
the upper molars and mesial movement of the lower molars. Retrusion
of the upper and protrusion of the lower incisors reduced the overjet.
Intrusion and protrusion of the lower incisors reduced the overbite.
The occlusal plane was rotated in clockwise direction as a result of
intruding the lower incisors and the upper molars. The maxillary and
mandibular arches were expanded at the front and rear during
treatment.

181
Controversies
in
Pre Adjusted
Appliance

182
Torque in the Base
vs
Torque in the Face
 By 1988, about 30 % of all American
orthodontists were using the straight wire
appliance, another 50% were using Partly
programmed edgewise appliances
 Patent restrictions allowed them to reproduce no
more than four of the eight vital features that
appear in fully programmed brackets
( David webb, ―A‖ company)

184
 The Torque In the base allows the slot
of the fully programmed bracket target
correctly on the crown‘s mid transverse
plane
 Torque in the face causes occluso
gingival variation in the placement of
slot point over mid transverse plane

185
 Hence the Torque in base was an important
issue with the first and second generation
PEA brackets because Level slot line up was
not possible with brackets designed for
Torque in Face.
 Modern Bracket systems like MBT system,
have been developed using CAD-CAM system

186
 The computer is first
able to locate the
precise location for the
bracket slot, relative to
in – out distance and
torque position for each
teeth. Once this position
is established, it can be
build up the in – fill
areas to optimize all
requirements of the
brackets

187
018 vs 022 Slot:
 Steiner introduced the 0.457 mm × 0.711
mm (0.018-inch × 0.028-inch) slot for
stainless steel wires in lieu of the 0.559 mm
× 0.711 mm (0.022-inch × 0.028-inch slot for
gold alloy wires.
 Original intention of 022 slot was not meant
for sliding mechanics, (as it is ideally suited)
but it is for Torque movement control when
22 X 28 gold wires were used

188
 With the advent of stainless steel
wires, edgewise brackets were redesigned
from 022 to 018 slot.
 022 slot however was superior when sliding
of teeth is necessary by the use of undersized
stiffer wires, but is inferior to 018 slot in
Effective torque expression due to limited
springiness and range of stiffer wires used in
wider slot.
018 vs 022 Slot:

189
 Role of Titanium arch wires became
evident in alignment and torque control
in wider 022 slot by the characteristics
like higher range and resistance to
permanent deformation.
 Even undersized stiffer wires are the
alternate solution
018 vs 022 Slot:

190
Bracket prescription
System
U1 U2 U3 U4 U5 L1 L2 L3 L4 L5
Tp Tq Tp Tq Tp Tq Tp Tq Tp Tq Tp Tq Tp Tq Tp Tq Tp Tq Tp Tq
Andrews 5/7 9/3 11/-7 0/-7 0/-7 0/-1 0/-1 5/-11 0/-17 0/-22
Roth 5/12 9/8 11/0 0/7 0/7 0/-7 0/-7 5/-11 0/-17 0/-22
Alexander 5/14 9/8 11/0 0/-7 0/-7 0/-5 0/-5 6/-7 0/-11 0/-17
Hilgers 5/22 9/14 11/7 0/-7 0/-7 0/-1 0/-1 5/7 0/-11 0/-17
Level Anchorage 5/14 9/8 6/0 0/-7 0/-7 0/-1 0/-1 6/0 4/-11 6/-11
Ricketts 5/22 8/14 5/7 0/0 0/0 0/-1 0/-1 5/7 0/0 0/-11
MBT 4/17 8/10 8/0 0/-7 0/-7 0/-6 0/-6 3/0 2/-12 2/-17
Sondhi 5/22 9/14 10/3 0/-7 0/-7 0/-1 0/-1 6/-7 0/-11 0/-17

191
In Andrew‘s Original System:
Concerning the 1st order information: There
is no antirotation system on any tooth, except
a 10 distal offset on upper molars.
Concerning the 2nd order information: Teeth
of the buccal segments all present a positive
angulation, meaning that they all have a
mesial crown tip, mostly for the 1st and 2nd
upper molars. www.indiandentalacademy.com

193
Concerning the 3rd order information:
On the upper arch:
- The upper incisor only has a 7 torque
- The upper canine has a negative torque of –
7,
equal to the torque of the biscuspids.
- The torque if slightly greater on molars.
On the Lower arch:
- The torque on the buccal segments is
progressive from the canines to the 2nd
molars. www.indiandentalacademy.com

194
A torque of 7° on central incisors was soon
found to be insufficient, since the play
between archwire and bracket slot, which
wasn‘t taken into account, creates important
loss of information during retraction stages
and hence the amount torque necessary to
compensate for the unwanted lingual tipping
was clearly greater than 7°

195
Andrew’s system soon got the
reputation of being an “anchorage
burning appliance” - - -
Increased tip in anterior brackets to compensate for
wagonwheel effect

196
In 1974, Ronold Roth:
Based on anticipation of relapse during and
after treatment came up with his fully
programmed universal appliance. Thus he
systematically included the information for
over correction in all three planes of space.

198
Concerning the 1st order information: All
teeth in the buccal segment – anti rotation
system. Upper molars reinforce distal
offset from 10 to 14 and lower molars 4
anti-rotation
 Concerning the 2nd order information :
Canine angulation increased to 11 to 13
Maxillary buccal segment lose their mesial
tip and are in more anchorage situation.www.indiandentalacademy.com

199
Concerning 3rd order information: The torque
on the upper incisors is increased by 5
- Torque on the upper canines decreased by 5
- Torque is markedly greater on molars. (-14
instead of -9 )
On the lower arch :
- Torque on the buccal segments stays identical to
Andrew’s except for a decrease from 35 to 30 on the
second molar which decreases the “rolling effect” (lingual
tip) sometimes noticed with Andrews’ torque.www.indiandentalacademy.com

200
Vari Simplex Discipline
 The most important angulation of the is the
-6 degrees angulation of the lower 1st molars.
 The mandibular first molars have this tip back
built in to promote leveling and to gain arch
length.
 The preservation of anchorage achieved using this
technique is in keeping with the original Tweed
principles

201
 In other systems, torque was developed
based on averages obtained by
measuring the dentition of untreated
ideal occlusions.
 The Vari-Simplex approach, however,
was to measure torque found in
rectangular archwires used to finish well
treated orthodontic cases.

202
 The 5º torque in mandibular incisor
brackets helps to move the incisal edge
of the mandibular incisors lingually (less
than 0.5 mm) and the root apices of
these tooth labially (approximately
1mm).

203
Hilgers prescription
 - Upper incisors have a considerably
increased torque. 22° for the central
incisor, 14 ° for the lateral incisor.
 - Upper canine has a 7 ° torque, this
creates a transverse differential of 14 °
between canine and biscuspid.

204
Ricketts Bioprogressive
therapy
 Bioprogressive therapy started initially with
placing torque in the upper anteriors only.
 This so called automatic torquing of the upper
incisor was a graduation of multiples of 7
degrees with the
 cuspid at 7º,
 lateral at 14º and
 central at 22º (may be it should have been 21º).

205
 The ―Full Torque Bioprogressive appliance‖
had built in torque for the lower posterior
brackets too.
 The same graduation for 7º, 14º and 22º
was incorporated here, too.
 Ricketts finally developed the ―Triple Control
Bioprogressive appliance‖ which also had
second molar tubes with 32º of torque.

206
MBT prescription
 Combination of Andrew‘s and Roth with few
changes
 Anti rotation system was removed, all the
excessive mesial tip has been removed.
 Upper incisors have markedly increased torque
of 17 ° and 10 ° and upper canine -7 ° torque.
 The torque on the lower incisors increase to - 6
°

207
CONTROVERSIES IN
ORTHOGNATHIC SURGERY
 THE USE OF RIGID INTERNAL FIXATION
 The most universally used method for stabilisation
of ractures and osteotomies ha been the use of
intermaxillary fixation (IMF).
 Common methods of IMF include the use of arch
bars , Ivy loops, cast splints or simply the use of
the orthodontic appliance.
 The introduction of rigid fixation has reduced the
time required for IMF which would otherwise be 3
to 8 weeks of immobilisation.

208
 THE USE OF RIGID INTERNAL
FIXATION
 Controversies in the use of Rigid internal
fixation include:
 Does RIF improve bony healing and post
operative osteotomy strength?
 Does it improve long term stability?
 Is there a greater chance of developing TMD
post operatively with RIF?

209
 THE USE OF RIGID INTERNAL
FIXATION
 It was Spiessl who first described the
use of bone screws for fixation of a
sagittal osteotomy in 1974.
 The various RIF systems include:
 Lag screws
 Bone plating
 Pin systems

210
 Advantages of rigid fixation:
 Reduction or elimination of IMF
 Period of IMF can vary from 2to three weeks or the
suregon may choose not to use IMF at all.
 Increased post operative safety
 More rapid bone healing
 Ability to check the post operative occlusion in
cases where segments have been displaced.
 Ability to stabilize osteotomies that would
otherwise be difficult to stabilise
 Better control of bony segments

211
 Advantages of rigid fixation:
 Increased stability
 More rapid reduction of oedema
 Improved condition of the TMJ and muscles of mastication
post operatively
 DISADVANTAGES:
 Technical difficulties
 Increased expense
 Increased risk of infection
 Need for plate and screw removal
 Neurosensory disturbances
 Tooth devitalisation
 TMJ symptoms

212
 TMJ considerations
in the use of RIF

214
 Kundert compared condylar displacement in patients
treated with sagittal osteotomies of the mandible with
screw fixation and wire fixation. The authors noted
condylar distraction in both groups with the magnitude
slightly greater in the screw fixation group.
J. Oral Surgery. 35: 881; 1977.
 A computed tomography study showed some medial
rotation of the condylar segment. Varying inter condylar
distances were also seen. However, screw fixation
apparently caused no major positioning problems of the
condylar bearing segments.
J. Maxillo face Surg. 12: 139; 1984.

215
-Timmis et al compared 28 patients with rigid fixation 14
patients treated with wire fixation . The wire osteosynthesis
group showed no statistical change in facial pain, TMJ pain or
clinical signs after surgery. The rigid fixation group however
showed significant decrease in TMJ noise, facial pain, and TMJ
pain.
Oral surg. 62: 119; 1986.

216
 Carter et al studied the effects of various fixation methods for mandibular
advancement surgery, they concluded that:
 After sagittal split osteotomies of the mandibular rami, horizontal rotation of the
condyle usually occurs, regardless of the type of fixation or the position of the
distal segment.
 2. There were statistically significant changes (p < 0.001) in the intercondylar
angles with all three types of fixation when the distal segments were measured
in the anterior and posterior positions. However, the clinical significance of these
changes was not proved.
 3. In the three methods of fixation, the only statistically significant difference (p
= 0.005) was between screw and wire osteosynthesis when the distal segments
were in the forward position.
 4. There were no consistent differences in horizontal rotation between the
condyles that were fixed first and those that were fixed second, for either the left
or right side.
 5. The size of the original intercondylar angle did not affect the magnitude of
change in the postoperative intercondylar angle, regardless of the position of the
distal segment or the type of fixation used.

217
 Less Rigid Wire
 Cause the teeth are
no longer used as
handles to the bone
(IMF), the extra
strength & rigidity are
unnecessary.
 More Rigid Wire
 During surgery patients
are still placed in IMF
before screw or plate
placement.
 Flexible orthodontic
appliance may lead to
erroneous segment
positioning & difficult
finishing

218
ROOT
RESORPTION
related to
ORTHODONTIC
TREATMENT

219
 Bates (1856) – 1st
to discuss root
resorption of
permanent teeth.
 Ottolengui (1914)
– related root
resorption to
orthodontic
treatment
Root resorption after treatment Part 2 –
Brezniak and Wasserstein AJO-DO Volume 1993 Feb (138 - 146)

220
Etiology
(Phillips, Reitan and Shafer et al)
 Physiologic tooth movement.
 Adjacent impacted tooth pressure.
 Periapical or periodontal inflammation.
 Tooth implantation / replantation.
 Continuous occlusal trauma.
 Tumors/cysts.
 Metabolic / systemic disturbances
 Local functional / behavioral problems.
 Nail –biting.
 Tongue thrust with open bite.
 Dilacerations.
 Orthodontic treatment
 Individual susceptibility.www.indiandentalacademy.com

221
Types of Root resorption
(Andresen)
 Surface resorption
 Inflammatory resorption
1. Transient
2. Progressive
 Replacement resorption
Root resorption after orthodontic treatment is
surface / transient inflammatory resorption

222
Controversies in factors influencing root
resorption
Alveolar bone density
 Becks,Tager,Reitan found Root
resorption is greater in dense bone.
 Wainwright – Density affects tooth
movement rate, but no relation to
extent of root resorption.

223
Fixed vs removable
 The use of fixed appliances is more damaging to
the roots
 Ketcham claimed that normal function is
disturbed by the splinting effect of orthodontic
fixed appliances over a long period that can
cause root resorption.
- Linge BO, Linge L. Apical root resorption in
upper anterior teeth.
Eur J Orthod 1983;5:173-83.

224
Begg V/s edgewise
 It is often stated that the light wire Begg
technique causes less root resorption than
edgewise
 Although maxillary incisor root resorption during
the Begg third stage has been documented
- Remmelnick HJ. The effect of anteroposterior
incisor repositioning on the root and cortical
plate: a follow-up study. J Clin Orthod
1984;18:42-9.

225
 There is no difference between these techniques,
but found that the frequency of root resorption
was significantly higher (48%) in traumatized
maxillary incisors when intruded by the Begg
technique compared with edgewise technique
(43%).
 Root resorption after orthodontic treatment of traumatized teeth.
Malmgren et al
AM J ORTHOD 1982;82:487-91.
Begg V/s edgewise

226
Type of Orthodontic movement
 The stress distribution along the roots during
bodily movement is less than the stress
concentration at the apex resulting from
tipping. Therefore risk of root resorption that is
due to bodily movement should be less than
that of tipping.
 Reitan K. Biomechanical principles and reactions. In:
Graber TM, Swain BF. Orthodontics current principles
and techniques. St. Louis: CV Mosby, 1985:101-92.

227
Degree of Orthodontic force
 Harry and Sims found the distribution of resorbed
lacunae was directly related to the amount of
stress on the root surface. They concluded that
higher stress causes more root resorption.
 According to Schwartz, applied force exceeding the
optimal level of 20 to 26 gm/cm2 causes
periodontal ischemia, which can lead to root
resorption.

228
Continuous vs
intermittent forces
 The pause in treatment with intermittent
forces allows the resorbed cementum to
heal and prevents further resorption.
- Oppenheim A. Human tissue response to
orthodontic intervention of short and long
duration. Am J Orthod 1942;28:263-301.

229
 On the other hand, intermittent forces
have been linked in their damaging effects
to jiggling forces.
 Hall A. Upper incisor root resorption during Stage II of the Begg
technique. Br J Orthod 1978;5:47-50
Continuous vs
intermittent forces

230
Orthodontic treatment timing
 Orthodontic treatment should begin as early as
possible since there is less root resorption in
developing roots and young patients show better
muscular adaptation to occlusal changes.
-Rosenberg HN. An evaluation of the incidence and amount of apical
root resorption and dilaceration occurring in orthodontically treated
teeth, having incompletely formed roots at the beginning of Begg
treatment. AM J ORTHOD 1972;61:524-5.

231
Orthodontic
treatment
and
temporomandibular
disorders

232
 The attention of the orthodontic
community regarding TMD however was
heightened in the late 1980s after
litigation involving the allegations that
orthodontic treatment was the
proximal cause of TMD in
orthodontic patients.

233
 In the 1980‘s articles in various journals
and trade magazines suggested that
orthodontic treatment might play a role in
initiating temperomandibular disorder.
 On the other hand it was also claimed
that orthodontic treatment might be
effective in alleviating the signs and
symptoms of TMD.

234
 The benefits of orthodontic treatment in the
management of Temperomandibular Disorder is
questionable, since the occlusion is considered
as having a limited role in the cause of TMD.
 But the potential detrimental effects of
orthodontic treatment on TMJ has captured the
attention of orthodontic community.

235
Some of the examples of Orthodontic
treatment which can lead to
Temperomandibular Disorders are :
- William E. Wyatt. Preventing adverse
effects on TMJ through orthodontic
treatment . AJO 1987; 91: 493 –499

236
1) Effect of headgear and/or class II elastics in
correction of Class II malocclusions with deep
interlocking cusps.
By the headgear force, as
the maxillary dentition is moved
backward the muscles of
mastication will attempt to
retract the mandible when the
patient closes into maximum
intercuspation.
This compensating
movement by the mandible can
put distal pressure on the
condyles and conceivably cause
an anterior dislocation of the
disk. www.indiandentalacademy.com

237
 The cross elastics have a little effect on TMJ. As
the jaw is pulled to one side, distal pressure is put
only on one condyle and chances of anterior
dislocation of disc. If it creates a TMJ problem
then elastics should be worn only during waking
hours so that the muscles can help to hold the
mandible forward because of muscle tension.
2) Effect of Cross elastics to correct the
midline

238
3) Effect of Reverse Headgear or Class
III Elastics for Correction of Class III
malocclusion :
 This again can put distal pressure on
the mandible. If there is a developing
problem, treatment is limited to waking
hours as muscle tension or tone,
positions the mandible forward.
 Since at night, the muscles are relaxed
and there is more distal pressure on
condyle since compensating muscle
activity is not in play.

239
 4) Effect of Lower Expansion and Upper
Contraction :
In most cases, the crowded lower anterior
teeth are in contact with the lingual of the upper
anterior teeth. There is a spacing in upper
anterior. The common request that the patient
makes is to close the spaces in the upper
anterior teeth. If a orthodontist tries to close
down the anterior (upper) spaces without
opening the bite, it may create a premature
contact with the lower anterior teeth and exert
distal pressure on the mandible that may result
in TMJ pain.

240
 The majority of orthodontically treated
cases mostly have dental deep bite at the
beginning.
 If the deep bite is treated by extrusion of
the posteriors, there will be increase in the
vertical dimension of the lower face.
 In most of the cases vertical dimension of
the lower face will largely tend to revert to
its original height.
5) The Retentive Phase :

241
As the bite deepens post treatment four
possible adverse effects can be seen.
 Spacing in upper anterior teeth.
 Crowding in lower anterior teeth.
 Tends to move maxillary dentition forward.
 Drives the mandible distally

242
Since most of the orthodontists give a 3 to 3
fixed retainer on both upper and lower anterior
teeth after the active treatment. These retainers
prevent
 Firstly, lower anterior teeth from
crowding or collapsing.
 Secondly, prevent the upper anterior
teeth from rotating, separating or
moving forward.www.indiandentalacademy.com

243
But at the same time the retainer
cannot prevent other two adverse
effects i.e. forward movement of
maxillary dentition and distal
movement of mandible, which can
again lead to TMJ problems.

244
 Numerous epidemiologic studies have shown a
significant prevalence, with an average of 32% reporting
at least one symptom of TMD and an average of 55%
demonstrating at least one clinical sign.
 Several investigators have noted that signs and
symptoms of TMD generally increase in frequency and
severity in the second decade of life.
1) What is the prevalence of signs and
symptoms of TMD in orthodontically
untreated population ?
-Williamson EH. Temporomandibular dysfunction in pretreatment
adolescent patients. AM J ORTHOD 1977;72:429-33.

245
 Two of the first major investigations sponsored
by the National Institute of Health revealed no
statistically significant differences between the
treated and untreated groups & the assumption
made by some authors that orthodontic
treatment can prevent symptoms of mandibular
dysfunction is disproven.
2) Does orthodontic treatment lead
to a greater incidence of TMD ?
-Sadowsky C, BeGole EA. Long-term status of temporomandibular joint function and
functional occlusion after orthodontic treatment. AM J ORTHOD 1980;78:201-12.
-Sadowsky C, Polson AM. Temporomandibular disorders and functional occlusion after
orthodontic treatment: results of two long-term studies. AM J ORTHOD 1984;86:386-90.www.indiandentalacademy.com

246
 Another study of the long term effects
of orthodontic treatment stated that
comprehensive orthodontic treatment
can be under taken without fear of
creating TMD problems.
- Larsson E, Ronnerman A. Mandibular dysfunction
symptoms in orthodontically treated patients ten years after
the completion of treatment. Eur J Orthod 1981;3:89-94.

247
 In the major longitudinal study conducted by
Dibbets et al consisting of 171 patients, 75 of
whom were treated by Begg mechanotherapy,
65 were treated by activator and 30 patients
were treated with chin cups, revealed that at the
end of treatment, fixed appliance group had a
higher percentage of objective symptoms than
did the functional group, but no differences
existed at the 20 year follow up evaluation.
3)Does the type of appliance (e.g. fixed functional or
orthodontic vs orthopedic) make a difference ?

248
4) Does the removal of teeth as part
of an orthodontic protocol lead to a
greater incidence of TMD ?
 View point articles and tests have strongly
associated the extraction of premolars
with the occurrence of TMD in orthodontic
patients.
 But clinical studies that have dealt with
this issue have not shown relationship
between premolar extraction and TMD.

249
 Sadowsky etal studied 160 patients and
reported that joint sounds were evident
before and after treatment in 87
extraction patients and 73 non extraction
orthodontic patients. They reported there
is no increase in the risk of development
of joint sounds regardless of whether
teeth were removed .
Sadowsky C, BeGole EA. Long-term status of temporomandibular joint function
and functional occlusion after orthodontic treatment.
AM J ORTHOD 1980;78:201-12.

250
5) Can orthodontic treatment lead to
a posterior displacement of the
mandibular condyle?
 A number of viewpoint articles have
asserted that a wide variety of traditional
orthodontic procedures e.g. premolar
extraction, extraoral traction, retraction of
maxillary anterior teeth cause TMD signs
and symptoms by producing a distal
displacement of condyle .

251
 Gianelly et al did the study collecting the
tomograms to evaluate condylar position.
They took the tomograms before orthodontic
treatment in 37 consecutive patients aged 10
to 18 years and compared them with
tomograms from 30 consecutively treated
patients with fixed mechanotherapy and
removal of four premolars. No differences in
condylar position were noted between groups .
- Longitudinal evaluation of condylar position :
Gianelly, Anderson, and Boffa 1991 AJO DO Nov 416 - 420

252
 Another study conducted by Luecke and
Johnston evaluated the pretreatment and
post treatment cephalograms of 42 patients
treated with fixed appliances in conjunction
with the removal of two upper premolars.
 The result of the study indicated that the
majority of patients about 70% undergo a
forward mandibular displacement and a
slight opening rotation of mandible. The
remainder of the sample had distal
movement of the condyle.
- Premolar extraction and mandibular position
Luecke and Johnston Jan AJODO 1992

253
 Thus researchers concluded that
posterior condyle position was not
a result of orthodontic treatment.

254
6) Should the occlusion of orthodontic
patients be treated to specific
gnathologic standards ?
 Several view point articles including those by
Roth et al and Williamson have maintained
that TMDs may result from a failure to treat
orthodontic patients to gnathologic standards
that include the establishment of a ―mutually
protected occlusion‖ and proper seating of the
mandibular condyle within the glenoid fossa.
-Roth RH, Gordon WW. Functional occlusion for the orthodontist.
Part IV. J Clin Orthod 1981;15:246-54,259-65.

255
 In contrast Pullinger et al reported that
small occlusal slides less then 1 mm are
common in asymptomatic subjects as
well as patients with TMD.
-Occlusal TMJ orthopedic relationships: Pullinger, Solberg,
Hollender, and Petersson,AJO DO1987 Mar 200 - 206

256
 The establishment of an occlusion that
meets gnathologic ideals probably is
unnecessary particularly in adolescent
patients and sometimes impossible to
attain in some adult patients .

257
 A trend toward decreased prevalence of
TMD signs and symptoms in treated
patients also was noted by Sadowsky ,
Polson and Dahl et al.

258
British Dental Journal 202, E2 (JAN 2007)
TMD and occlusion part I. Damned if we do? Occlusion:
the interface of dentistry and orthodontics
Evidence is lacking to suggest static
occlusal factors cause TMD.

259
British Dental Journal 202, E3 (JAN 2007)
TMD and occlusion part II. Damned if we don't?
Functional occlusal problems: TMD epidemiology in
a wider context
Evidence is lacking to suggest
functional occlusal factors cause TMD.
Investigation of other aetiological
factors has been relatively neglected.

260
Conclusion
Controversies go hand in hand with any
science especially with Orthodontics. The
only way to resolve these controversies is by
moving on from traditional ―Opinion based
Orthodontics‖ to ―Evidence based
Orthodontics‖

261
Thank you

262
References
 Proffit ―Contemporary orthodontics‖.
 Birte Melson ―Current controversies in orthodontics‖
 Samir E. Bishara ―Third molars: A dilemma! Or is
it?‖ Am J Orthod Dentofacial Orthop 1999; 115: 628-
33.
 Margaret E. Richardson ―The role of the third
molars in the cause of late lower arch crowding: A
review.‖ Am J Orthod Dentofac Orthop 1989; 95 : 79-
83.

263
 Naphtali Brezniak, Atalia Wasserstein ―Root resorption
after orthodontic treatment: Part 1 and Part 2 – Literature
review.‖ Am J Orthod Dentofac Orthop 1993; 103(1) : 62-66
and 138-146.
 James A. McNamara, Donald A. Seligman and Jeffrey P.
Okeson ―Occlusion, Orthodontic treatment and
temporomandibular disorders – A review.‖ Journal Orofacial
Pain 1995; 9 : 73-90.
 L.R. Dermaut, C.M.F. Aelbers ―Orthopedics in orthodontics:
Fiction or reality. A review of literature Part I and Part II.‖ Am J
Orthod Dentofac Orthop 1996; 110 : 513-519 and 667-671.
 Donald G. Woodside ―Do functional appliances have an
orthopedic effect?‖ Am J Orthod Dentofac Orthop 1998; 113(1)
: 11-14.

264
 William E. Wyatt. Preventing adverse effects
on TMJ through orthodontic treatment . AJO
1987; 91: 493 –499
 Reint M. Reynders Orthodontics and
temporomandibular disorders: A review of the
literature (1966-1988) AJO 1990; 97: 463-471
 Sadowsky C, BeGole EA. Long-term status of
temporomandibular joint function and
functional occlusion after orthodontic
treatment. AM J ORTHOD 1980;78:201-12.

265
 James A.McNamara,Jr., Orthodontic treatment and
temperomandibular disorders.OOO 1997;83 : 107-117
 Burton H.Goldstein . Temperomandibular disorders .OOO
1999 ;88:379-383
 Ambiguities of Angle‘s classification :
1989 No. 4, 295 - 298Donald J. Rinchuse, Daniel J.
Rinchuse
 A matter of Class: interpreting subdivision in a
malocclusion.

266
 Diagnostic value of plaster models in Contemporary
Orthodontics:
Seminar in Orthodontics 3rd issue 2005.
 Rheude B, Sadowsky Pl, Ferriera A, Jacabson A. An evaluation
of the use of digital study models in orthodontic diagnosis and
treatment planning Angle Ortghod 75: 292-296, 2005
 Han U. Consistency of orthodontic treatment decisions relative
to diagnostic records
AJO DO 1991, 100: 212-219
 Reliability of Digital vs Conventional cephalometric Radiology: A
comparative evaluation of landmark identification error. Scott
R. Mclure etal Seminar in Orthodontics 3rd Issue 2005.

267
- The Extraction debate of 1911 by case, Dewey and
cryer. Discussion of case: The question of e traction
in orthodontia. AJO 50: 751,1964
 The effects of buccal corridor spaces and arch form
on smile esthetics
Roden-Johson D., Gallerano R, English J AJODFO
2005, 127: 343-50
 Mandibular third molars and post retention crowding
Kaplan R. AJO DO 1974 ;66:411-430
 Root resorption after treatment Part 2 – Brezniak and
Wasserstein AJO-DO Volume 1993 Feb (138 - 146)

268
 Linge BO, Linge L. Apical root resorption in upper anterior teeth.
Eur J Orthod 1983;5:173-83.
 Remmelnick HJ. The effect of anteroposterior incisor repositioning on
the root and cortical plate: a follow-up study. J Clin Orthod
1984;18:42-9.
 Root resorption after orthodontic treatment of traumatized teeth.
Malmgren et al
AM J ORTHOD 1982;82:487-91.
 Reitan K. Biomechanical principles and reactions. In: Graber TM, Swain
BF. Orthodontics current principles and techniques. St. Louis: CV
Mosby, 1985:101-92.

269
 Oppenheim A. Human tissue response to orthodontic intervention of
short and long duration. Am J Orthod 1942;28:263-301.
 Hall A. Upper incisor root resorption during Stage II of the Begg
technique. Br J Orthod 1978;5:47-50
 Rosenberg HN. An evaluation of the incidence and amount of apical
root resorption and dilaceration occurring in orthodontically treated
teeth, having incompletely formed roots at the beginning of Begg
treatment. AM J ORTHOD 1972;61:524-5
 Pancherz H, Anchus-Pancherz M. The headgear effect of the Herbst
appliance: a cephalometric long-term study Am J Orthod Dentofac
Orthop 1993;103:510-20.

270
 Wieslander L, Buck DL. Physiologic recovery after cervical
traction therapy. Am J Orthod 1974;66:294-301.
 DeVicenzo JP. Changes in mandibular length before, during, and
after successful orthopedic correction of Class II malocclusions
using a functional appliance. Am J Orthod Dentofac Orthop
1991;99:241-51.
 Assessment of Orthodontic Treatment Outcomes: Early
Treatment versus Late Treatment: Tsung-Ju Hsieh, Yuliya
Pinskaya, W. Eugene Roberts, he Angle Orthodontist: Vol. 75,
No. 2, pp. 162–170

271
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