This document defines and discusses the etiology, features, assessment, treatment planning and management of Class II division 1 malocclusions. Key points include: - Class II division 1 malocclusions are characterized by proclined upper incisors and a large overjet. The etiology can include skeletal, dental, soft tissue and habit factors. - Treatment planning depends on factors like age, difficulty, stability, and facial aesthetics. It may involve early treatment, functional appliances, fixed appliances with/without extractions, or growth modification/orthodontic camouflage/surgery. - Stability after treatment requires full reduction of the overjet and achievement of lip competence through retention.

1. B Y: B AT O O L M O H A M M E D FA R H A N
CLASS II DIVISION 1

2. CONTENTS
 Definition
 Etiology
 Occlusal features
 Assessment of and treatment planning in Class II
division 1 malocclusions
Early treatment
Management of an increased overjet associated with a
Class I or mild Class II skeletal pattern
 Management of an increased overjet associated with
a moderate to severe Class II skeletal pattern
Retention

3. DEFINITION
• is when the maxillary anterior teeth are proclined and a
large overjet is present.

4. ETIOLOGY
• Skeletal pattern
A Class II division 1 incisor relationship is usually
associated with a Class II skeletal pattern,
commonly due to a retrognathic mandible

5. ETIOLOGY
• Soft tissues
the resting position of the patient's soft tissues and their functional activity
also play a part.
in one of the following ways
• circumoral muscular activity
to achieve a lip-to-lip seal
• the mandible is postured forwards to allow the
lips to meet at rest
• the lower lip is drawn up behind the upper lndsors
• the tongue is placed forwards between the incisors to contact the
lower lip, often contributing to the development of an incomplete
overbite:
• Acombination of these

6. ETIOLOGY
• Dental factors
A Class II division 1 incisor relationship may occur
in the presence of crowding or spacing. Where the
arches are crowded, lack of space may result in
the upper incisors being crowded out of the arch
labially and thus to exacerbation of the overjet.

7. ETIOLOGY
• Habits
A persistent digit-sucking habit will act like an orthodontic
force upon the teeth if indulged in for more than a few
hours per day. The severity of the effects produced will
depend upon the duration and the intensity, but the
following are commonly associated with a determined habit

8. OCCLUSAL FEATURES
The overjet is increased
 the upper incisors may be proclined or upright
 The overbite is often increased
forward adaptive tongue position
 a habit, or increased vertical skeletal proportions.
 an anterior open bite
preexisting gingivitis.

9. ASSESSMENT OF AND TREATMENT
PLANNING IN CLASS II DIVISION 1
MALOCCLUSIONS
 Factors influencing a definitive treatment plan
 The patient's age
 The difficulty of treatment
 The likely stability of overjet reduction
 The patient's facial appearance

10. ASSESSMENT OF AND TREATMENT
PLANNING IN CLASS II DIVISION 1
MALOCCLUSIONS
 Practical treatment planning
The decision as to whether extractions are required will
depend upon
1. the presence of crowding
2. the tooth movements planned
3. their anchorage requirements
• Class Il division 1 malocclusions are commonly
associated with increased overbite, which must be
reduced before the overjet can be reduced.
• Overbite reduction requires space (about 1-2 mm for an
averagely increased overbite)

11. • Where the lower arch is well aligned and the molar relationship is Class
II, space for overjet reduction can be gained by distal movement of the
upper buccal segments or by extractions.
• a Class I buccal segment relationship is preferable.
• If extractions are carried out in the upper arch only, the molar
relationship at the end of treatment will be Class II.
• This is functionally satisfactory, but as half a molar width is narrower
than a premolar, some residual space often remains in the upper . arch.
• However with fixed appliances. the upper first molar can be rotated
mesiopalataJJy to take up this space by virtue of its rhomboid shape.
• is usually considered if the molar relationship is half a unit Class II or
less,
• a full unit of space can be gained in a co-operative, growing patient

12. • appliances have been developed which aim to produce
distal movement of the molars. These have been
classified as follows:
• Inter-maxillary: anchorage derived from within the arch -
anterior teeth, premolars, coverage of palatal vault.
• Intra-maxillary: anchorage derived from opposing arch.
In Class II cases this is the lower arch.
• Absolute anchorage: anchorage derived from implants.
Examples include microimplants and palatal implants.

13. EARLY TREATMENT
• Preadolescent children were randomized to either
observation or to early treatment with either a functional
appliance or headgear.
• Following this phase, patients underwent
comprehensive treatment with fixed appliances in the
permanent dentition.
• The results indicated that the early skeletal effects are
not maintained long-term.
• the time in fixed appliances was reduced for children
who underwent early treatment the overall treatment
time was considerably longer if the early treatment time
was included

14. EARLY TREATMENT
• At present many clinicians feel that treatment is best
deferred until the eruption of the secondary dentition
where space can be gained for relief of crowding and
reduction of the overjet by the extraction of permanent
teeth (if indicated),
• soft tissue maturity increases the likelihood of lip
competence.
• In the interim a custom-made mouthguard can be worn
for sports.

15. • if the upper incisors are thought to be at particular risk of
trauma during the mixed dentition, treatment with a
functional appliance can be considered

16. • Boy aged 9 years with
a Class II division 1
malocclusion on a
Class II skeletal
pattern.
• As the upper incisors
were at risk of trauma,
treatment was started
early with a functional
appliance.

17. • . Following eruption of the
permanent dentition, definitive
treatment involving the
extraction of all four second
premolars and the use of fixed
appliances was carried out to
correct the inter-incisal angle
and alleviate thecrowding
 (note the retroclination of the
upper incisors as most of the
reduction of the overjet has
been achieved by
dentoalveolar change)

18. MANAGEMENT OF AN INCREASED
OVERJET ASSOCIATED WITH A CLASS I
OR MILD CLASS II SKELETAL PATTERN
• Fixed appliances, with extractions if indicated, will give
good results in skilled hands in this group
• In patients with moderately crowded arches. lower
second premolars and upper first premolars are a
common extraction pattern as this favours forward
movement of the lower molar to aid correction of the
molar relationship and retraction of the upper labial
segment.

19. CLASS II DIVISION 1 MALOCCLUSION
ON A CLASS I SKELETAL PATTERN
WITH CROWDING

20. • A functional appliance can be used to
A. reduce an overjet in a cooperative child with well-
aligned arches
B. a mild to moderate Class II skeletal pattern
• provided that treatment is timed for the pubertal growth
spurt

21. • In a limited number of cases with good arch alignment.
no crowding and proclined upper incisors a removable
appliance can be considered

22. MANAGEMENT OF AN INCREASED OVERJET
ASSOCIATED WITH A MODERATE TO SEVERE
CLASS II SKELETAL PATTERN
Management of the more severe case is the province of
the experienced operator.
There are three possible approaches to treatment
1. Growth modification
2. Orthodontic camouflage
3. Surgical correction

23. GROWTH MODIFICATION
• by attempting restraint of maxillary growth, by
encouraging mandibular growth, or by a combination of
the two

24. ORTHODONTIC CAMOUFLAGE
• using fixed appliances to achieve bodily retraction of the
upper incisors .
• The severity of the case that can be approached in this
way is limited by the availability of cortical bone palatal to
the upper incisors and by the patient's facial profile.
• If headgear is used in conjunction with this approach, a
degree of growth modification may also be produced in
favourably growing children.

25. PATIENT WITH CLASS II DIVISION 1 MALOCCLUSION ON A
MODERATELY SEVERE CLASS II SKELETAL PATTERN TREATED BY
ORTHODONTIC CAMOUFLAGE IN WHICH BOTH UPPER FIRST
PREMOLARS WERE EXTRACTED TO GAIN SPACE FOR OVERJET
REDUCTION AND FIXED APPLIANCES WERE USED FOR BODILY
RETRACTION OF THE UPPER INCISORS

26. SURGICAL CORRECTION
• In cases with a severe Class II skeletal pattern,
particularly where the I lower facial height is significantly
increased or reduced, a combination of orthodontics and
surgery may be required to produce an aesthetic and
stable correction of the malocclusion
• The threshold for surgery is lower in adults because of a
lack of growth.

27. RETENTION
• retention must be considered during treatment planning.
• Provided that the upper incisors have been retracted to a
position of soft tissue balance and are controlled by the
lower lip, the prognosis is good.
• To aid stability, full reduction of the overjet and the
achievement of lip competence is advisable.
• If the overjet is not fully reduced there is the risk that the
lower lip will continue to function behind the upper
incisors, with a subsequent relapse in incisor position.