1. The study compared treatment outcomes for identical twin sisters with Class III malocclusions who underwent either 1-phase or 2-phase treatment. One twin received early crossbite correction followed by fixed appliances (2-phase), while the other received only fixed appliances (1-phase). 2. After treatment, both twins achieved almost identical dental results despite differences in treatment approach. This implied that early treatment had no impact on jaw growth, which was dominated by genetic factors. 3. While early treatment did not influence growth, it simplified subsequent treatment. Therefore, 2-phase treatment may be better suited than 1-phase treatment for mild-moderate Class III cases. However, criteria for the treatment approach depend on

1. A Very Good Afternoon
1 phase versus 2 phase

2. Under the guidance of :
Dr. Mohammad Mushtaq,
PROFFESSOR & HOD
By:
Sneh Kalgotra,
2nd Year P.G.
Department of Orthodontics &
Dentofacial Orthopaedics, GDC&H,
Srinagar.dital jet versus pendulum appliance

3. One-phase vs 2-phase treatment for
developing Class III malocclusion: A
comparison of identical
Twins.
Junji Sugawara,
Zaher Aymach,
Hiromichi Hin,
Ravindra Nanda.
1 phase versus 2 phase

4. About the authors
1 phase versus 2 phase
Ravindra Nanda (born 19
February 1943) is the
professor and Head of
CraniofacialDepartment and
Chair of the Division of
Orthodontics at the
University of Connecticut
School of Dental Medicine.
He is an innovator of various
appliances in orthodontics.
With 10 books and 105
artcles to his credit
Ravindra Nanda
Dr. Nanda receiving
Life membership of

5. About the authors
Private practice, Nagoya, Japan.
Has 9 publications to his credit.
1 phase versus 2 phase
Junji Sugawara
Zaher Aymach
Lecturer and assistant researcher,
Division of Maxillofacial Surgery,
Tohoku .University, Sendai, Japan.
Has 63 publications to his credit.

6. prolouge
• In the treatment of skeletal Class III
growing patients, it has become a common
practice to intervene early with orthodontic
or orthopedic treatment modalities as a part
of a 2-phase treatment approach.
• Although orthopedic forces that attempt to
control or alter the skeletal framework in
skeletal Class III patients appear to be
remarkably effective in the initial stages, the
results are rarely maintained in the long term.
1 phase versus 2 phase

7. Therefore, the key question is “what differences in
jaw growth or treatment modality and outcome will
there be between patients who undergo 1-phase
treatment and those who don’t?”
1 phase versus 2 phase

8. Critical appraisal of title
• One-phase vs 2-phase treatment for developing Class III
malocclusion: A comparison of identical twins.
 Title reflects the aim of the study.
 Variables are not clearly mentioned in the title.
 The type of study is not mentioned in the title.
 It comprises of 16words- appropriate.
 It is not specific.
 Title is incomplete as it suggest nothing about the
parameters being undertaken in the study.1 phase versus 2 phase

9. Proposed alternative title
One-phase vs 2-phase treatment for mild
to moderate developing Class III
malocclusion: A comparison of identical
twins- A case report.
- 19 words.
1 phase versus 2 phase

10. Critical appraisal of the abstract
 Its informative and comprehensive in its
contents.
 Gives brief overview of the whole study.
Key words are NOT clearly mentioned.
1 phase versus 2 phase

11. CRITICAL APPRAISAL OF INTRODUCTION
 Introduction is meaningful.
 Introduction is SHORT.
 It is built on the existing literature.
 Citations that are reported, are relevant and
pertinent to the study and followed with correct
references in the list.
 Purpose of the study is clearly mentioned in the
introduction. 1 phase versus 2 phase

12. Material and methods
The patients,
monozygotic twin
sisters (Fig 2),
were referred to
our department at
Tohoku University,
Sendai, Japan, in
1996 when they
were 9 years old
for orthodontic
treatment of
anterior crossbites.
1 phase versus 2 phase
Fig 2

13. Material and methods
Both twins had
almost the same
orthodontic
problems that
included a
prognathic profile,
mild mandibular
asymmetry, Class
III denture bases,
deviation of
mandibular midlines,
and occlusal
interference
of the incisors (Fig
3).
1 phase versus 2 phase
Fig 3

14. Material and methods
Cephalometrically,
their skeletofacial
types were
classified as Class
III short-face
types. The short-
face tendency was
more pronounced in
Patient 2 (Fig 4).
1 phase versus 2 phase
Fig – 4

15. 1 phase versus 2 phase

16. Material and methods
Treatment objectives for Patient 1 were
established with the 2-phase treatment approach,
whereas Patient 2 was managed with a 1-phase
treatment concept.
The treatment objectives for Patient 1 were
(1) Phase 1 treatment involving dental correction
of the anterior crossbite,
(2) growth monitoring and oral health care until
the postadolescent period,
(3) fixed appliance treatment for correction of
the remaining orthodontic problems, and
(4) retention and long-term follow-up.1 phase versus 2 phase

17. Material and methods
For Patient 2, the treatment objectives
were
(1) growth monitoring and oral health care
until the post adolescent period,
(2) correction of the malocclusion with
fixed appliance treatment together with
skeletal anchorage that would allow us to
circumvent the need for mandibular
premolar extraction, and
(3) retention and long-term follow-up.
1 phase versus 2 phase

18. Treatment progressIn Patient 1, the
first phase of
treatment began
with facemask
therapy and 2 x 4
appliances. The aim
was to correct her
anterior crossbite
dentally. The
crossbite and
maxillary dental
midline shift were
corrected in 6
months.
1 phase versus 2 phase

19. At the age of 10 and
after the first phase
of treatment, Patient
1's prognathic profile
and dental
malocclusion had
improved
significantly. At the
same time, growth
observation in
Patient 2 showed
that all her
orthodontic problems
were exactly as they
had been at the
initial examination.1 phase versus 2 phase

20. Before the second phase of treatment,
• Patient 1 still had a prognathic profile,
with some minor dental problems,
particularly in the mandibular dentition.
She had a lateral crossbite on the right
side, a mild Class III denture base, and
mild mandibular incisor crowding. At the
same stage,
• Patient 2 demonstrated more severe
orthodontic problems than her sister did
at this age. She had a skeletal Class III
malocclusion with a short-face tendency,
premature contact at the incisors, a dental
midline shift, an anterior crossbite, severe
crowding of the maxillary anterior teeth,
and retroclined mandibular incisors.
1 phase versus 2 phase

21. 1 phase versus 2 phase
Patient 1's
orthodontic
problems,
preadjusted fixed
appliance treatment
was started, and
short Class III
elastics were used to
improve the Class
III denture bases
and prevent
proclination of the
mandibular incisors
during leveling and
aligning.

22. Treatment for
Patient 2 started with bonding brackets on
the mandibular teeth and placing resin caps
on the maxillary molars to open the bite for
maxillary bonding. Open-coil springs were
used to make space and procline the
maxillary incisors. Simultaneously,
distalization of the mandibular posterior
teeth was started with the skeletal
anchorage system, which uses an orthodontic
miniplate as a temporary anchorage device
1 phase versus 2 phase

23. After 12 months of active fixed appliance treatment,
Patient 1's malocclusion was corrected. She obtained
a balanced profile, with adequate overjet and overbite,
proper anterior guidance, and rigid posterior
intercuspation of the teeth.
On the other hand, Patient 2's treatment
with the skeletal anchorage system lasted 18
months. She also achieved an acceptable Class I
occlusion and a satisfactory profile at debonding.
• After 30 months of retention, both twins have
maintained a good occlusion except for a minor
relapse of the maxillary right first premolar in
Patient 2. Overall, satisfactory results were
achieved.
1 phase versus 2 phase

24. 1 phase versus 2 phase

25. 1 phase versus 2 phase

26. COMPARISON OF TREATMENT PROGRESS AND
RESULTS IN THE TWINS
Comparisons of the twin sisters took
place at 4 time intervals
1. The initial examination was at age 9
years. Because they are monozygotic
twins, it is no surprise that even their
dentitions were almost identical.
1 phase versus 2 phase

27. 2.After Patient 1's first phase of treatment
(age, 10 years), the clinical pictures clearly
show the efficiency of early intervention for
her. Cephalometric superimposition shows
significant dentofacial differences between
the sisters at this stage. Patient 1's
crossbite was corrected by proclinatoin of
her maxillary incisors, forward displacement
of the maxilla, and clockwise rotation of the
mandible. This gave her an orthognathic
facial profile compared with Patient 2.
1 phase versus 2 phase

28. 3. Before fixed appliance treatment (age, 16
years), the skeletal differences between
them at 10 years gradually disappeared
during the pubertal growth spurt, and almost
no difference could be observed between
their skeletal profiles at 16 years. The only
difference perhaps was in the position of
the maxillary incisors. The orthodontic
effect of the facemask could still be seen on
Patient 1's maxillary Incisors.
1 phase versus 2 phase

29. 1 phase versus 2 phase

30. 4. During the retention period (age, 20
years), we superimposed the twins’ final
records. Interestingly, although they
underwent orthodontic treatment with
completely different treatment regimens
(1-phase vs 2-phase), their dentofacial
morphologies were identical .
1 phase versus 2 phase

31. Critical appraisal of material and
methods
The local ethical committee was not
consulted.
Informed and written consent was
obtained before the treatment was
started both from the patients and the
parents.
1 phase versus 2 phase

32. Critical appraisal of material and
methods
 It is an experimental study.
 Pre-test, post- test comparisons are used.
 Parameters used for maxillary length and mandibular
length are not clearly mentioned.
 since authors believe that phase 1 treatment has any
positive effect on psychology of the patient than it is
ethically wrong to give benefit of such treatment to one
patient only.
 One advantage of the study is it rules out the
bias produced due to genetics.
1 phase versus 2 phase

33. DISCUSSION
• The advantage of using monozygotic twins in
such a comparative case report is that all
differences in skeletal growth, beyond the
error of measurement, can be assumed to be
nongenetic and, therefore, the result of the
environment.
• Recent clinical trials have suggested that in the
longterm the improvement in the skeletal
malocclusion obtained after a first phase of
treatment is not significant when compared with
a control group that had no growth modification
treatment.
1 phase versus 2 phase

34. It was obvious that the early correction of
the anterior crossbite did not make a positive
impact on jaw growth. It seems that
morphogenetic factors are still stronger and
much more dominant than environmental
factors in the matter of jaw growth.
Patient 2 who was managed with a 1-phase
treatment, had to undergo treatment with the
skeletal anchorage system. The skeletal
anchorage system is a viable modality for
distalizing mandibular molars.
1 phase versus 2 phase

35. Conclusion
1. In spite of the differences in
treatment timing and modalities (1-
phase vs 2-phase treatment), both twin
sisters achieved almost identical
dentofacial results. This implies that
early treatment had no impact on jaw
growth in the pubertal growth period.1 phase versus 2 phase

36. Conclusion
2. Although phase 1 treatment had no impact on jaw
growth, it made the phase 2 treatment simpler and
easier. Therefore, 2-phase treatment might be more
suited for mild to moderate Class III patients than 1-
phase treatment.
3. The criteria for the selection of 1-phase or 2-phase
treatment depend entirely on the patient’s
requirements.
Because the biologic outcome is the same, the basis for
opting for a particular treatment regimen can be
complicated. Cultural, environmental, and psychosocial
factors need to be considered more carefully.
1 phase versus 2 phase

37. Review of literature
1 phase versus 2 phase

38. Outcomes in a 2-phase randomized clinical trial of early
class II treatment
J.F.Camilla Tulloch, William R Proffit, Ceib Phillips.
(AJODO 125, JUNE 2004).
The differences created between the treated
children and untreated control group by phase 1
treatment before adolescence disappeared
when both groups received comprehensive fixed
appliance treatment during adolescence.
This suggests that 2-phase treatment started
before adolescence in the mixed dentition
might be no more clinically effective than 1-
phase treatment started during adolescence in
the early permanent dentition.
1 phase versus 2 phase

39. Two phase treatment of Class III malocclusion.
Siddegowda R, Sahoo KC, Jain S
• The earlier the intervention, the
greater the chances of positive
response, regarding transversal
maxillary advancement.
1 phase versus 2 phase

40. Is early class III protraction facemask
treatment effective? A multicentre,
randomized, controlled trial: 15‐month follow‐up.
JCO 2010.
• Early class III orthopaedic treatment, with
protraction facemask, in patients under
10 years of age, is skeletally and dentally
effective in the short term and does not result
in TMJ dysfunction. Seventy per cent of
patients had successful treatment, defined as
achieving a positive overjet. However, early
treatment does not seem to confer a clinically
significant psychosocial benefit.
1 phase versus 2 phase

41. Is early class III protraction facemask
treatment effective? A multicentre,
randomized, controlled trial: 3-year
follow-up
JO 2012.
• The favourable effect of early class III
protraction facemask treatment
undertaken in patients under 10 years of
age, is maintained at 3-year follow-up in
terms of ANB, overjet and % PAR
improvement. The direct protraction
treatment effect at SNA is still
favourable although not statistically
significantly better than the CG.1 phase versus 2 phase

42. Moyers R. Handbook of orthodontics. 4th ed. Chicago:
Year
Book; 1988. p. 346-7, 433-4.
• “there is no assurance that the results
of early treatment will be sustained and
that 2-phased treatment will always
lengthen overall treatment time. Early
treatment not only may do some damage
or prolong therapy, it may exhaust the
child’s spirit of cooperation and
compliance.”
1 phase versus 2 phase

43. Critical reflection
1 phase versus 2 phase

44. Critical reflection
• This article is very relevant for day to day
patient care.
• Further studies need to be undertaken.
• Considerations like environmental factors
• And psycho-social factors should be
concerned.
1 phase versus 2 phase

45. References
1. Gebeile-Chauty S, Perret M, Schott AM, Akin JJ. Early
treatment of
Class III: a long-term cohort study. Orthod Fr 2010;81:245-54.
2. Kanno Z, Kim Y, Soma K. Early correction of a developing skeletal
Class III malocclusion. Angle Orthod 2007;77:549-56.
3. Mandall N, DiBiase A, Littlewood S, Nute S, Stivaros N,
McDowall R, et al. Is early Class III protraction facemask
treatment
effective? A multicentre, randomized, controlled trial: 15-month
follow-up. J Orthod 2010;37:149-61.
4. Sugawara J, Asano T, Endo N, Mitani H. Long-term effects of
chincap
therapy on skeletal profile in mandibular prognathism. Am J
Orthod Dentofacial Orthop 1990;98:127-33.
5. Mitani H, Sato K, Sugawara J. Growth of mandibular prongathism
after pubertal growth peak. Am J Orthod Dentofacial Orthop
1993;
104:330-6.
1 phase versus 2 phase

46. 6. Sugawara J, Asano T. The clinical practice guideline
for treatment
of developing Class III malocclusion. In: Sugawara J,
Asano T, editors.
Seeking a consensus for Class III treatment. Osaka,
Japan:
Tokyo Rinsho Shuppan; 2002. p. 21-30.
7. Sugawara J. Clinical practice guidelines for
developing Class III
malocclusion. In: Nanda R, editor. Biomechanics and
esthetic strategies
in clinical orthodontics. St Louis: Elsevier; 2005. p.
211-42.
1 phase versus 2 phase

47. 8. Sugawara J, Mitani H. Facial growth of skeletal Class III
malocclusion
and the effects, limitations, and long-term dentofacial
adaptations to chincap therapy. Semin Orthod 1997;3:244-54.
9. Skieller V, Bj€ork A, Linde-Hansen T. Prediction of mandibular
growth rotation evaluated from a longitudinal implant sample.
Am J Orthod 1984;86:359-70.
10. Bj€ork A, Skieller V. Normal and abnormal growth of mandible.
A
longitudinal cephalometric implantation study over a 25-year
period. Inf Orthod Kieferorthop 1984;16:55-108.
11. Sugawara J. A bioefficient skeletal anchorage system. In:
Nanda R, editor. Biomechanics and esthetic strategies in clinical
orthodontics. St Louis: Elsevier; 2005. p. 295-309.
1 phase versus 2 phase