class 2 malocclusion

 According to British Standards classification: “The
lower incisor edges lie posterior to the cingulum
plateau of the upper incisors, there is an increase in
overjet and the upper central incisors are usually
proclined.”

etiology
Skeletal
pattern
Soft
tissue
habits
Dental
factors

• Usually associated with
skeletal Class II pattern,
due to retrognathic
mandible.
• Proclination of the upper
incisors &/or retroclination
of the lower incisors by a
habit or the soft tissues
can result in an increase
in overjet on skeletal
Class I or even a Class III
pattern

 Influence of soft tissue is mainly mediated by skeletal
pattern, antero-posteriorly & vertically.
 Patient’s lips are incompetent, try to achieve anterior oral
seal in one of the following ways:
 Circumoral muscular activity.
 Forward postured mandible
 Lower lip is drawn up behind the upper incisors.
 Tongue is placed forward between incisors to contact
lower lip.
 Combination of these.

 DIGIT SUCKING: –
 Proclination of the upper
incisors.
 Retroclination of the lower
labial segment.
 Incomplete overbite or
localized anterior open
bite.
 Narrowing of maxillary
arch, Due to alteration in
the balance between
cheek & tongue pressure.

 Crowding in upper incisors out of the arch labially
result in exacerbation of the overjet

 Increased overjet.
 Often increased overbite.
 Incompetent lips.
 Class II molar, canine & incisor relationship.

 Angle’s Class II div 2 malocclusion is characterized
by Class II Molar relation.
 It is when the buccal groove of the first mandibular
molar occludes distal to the mesiobuccal cusp of the
first maxillary molar, with retroclination of the
maxillary central incisors
 Incidence : 5 – 10 %

 The lower incisor edges occlude posterior to the
cingulum plateau of the upper incisors and the
lower centrals are retroclined

 Van der Linden classification of Class II Div 2
depending on the spatial conditions in the maxillary
dental arch :
Type A
 The upper central and lateral incisors are retroclined. It
is of less severe in nature.

Type B-:
 The central incisors are retroclined and overlapped
by the lateral incisors
Type C-:
The central and lateral incisors are retroclined and
overlapped by the canines.

1) squarish face (Brachycephalic).
2) Upper lip is invariably short and positioned high with
respect to the upper anteriors.
3) Lower lip is thick flabby covering the upper incisors and
exhibiting
4) Usually straight to mildly convex profile because of less
skeletal discrepancy and the retroclined incisors
5) Deep mentolabial sulcus

1) Class II molar relation indicating distal relation of
mandible to the maxilla.
2) Decreased overjet, an increased overbite.
3) Deep bite usually traumatic

1) The upper arch is usually broad, ‘U’ shaped.
2) The palatal vault is usually deep.
3) An exaggerated curve of spee

 Diagnosis is the process of attempting to determine or
identify a possible disease or disorder
 (Extra oral and Intra oral features)
CLINICAL EVALUATION
 Case history , Photographic analysis ,
 Radiographic analysis , Cast analysis ,
DIAGNOSTIC AIDS
 Examination of the tempromandibular joint
 Examination of orofacial dysfunction
FUNCTIONAL ANALYSIS

Extra-oral
Photographic
analysis
Class II divison 1
profile: convex
Shape of head : dolicocephalic
Mento labial sulcus : shallow/deep
Class II divison 2
Profile : straight / convex
Shape of head : mesocephalic
/dolichocephalic
Mento labial sulcus : normal

 classII molar relation,
that may vary from end on
molar to fully fledged class II
o proclined maxillary anteriors
with resultant increased overjet
o spaced dentition

V – shaped palatal arch
Excessive curve of spee
Deep palate
Increased over jet

 Excessive lingual
inclination of
the maxillary central incisors
overlapped on the labial by
the maxillary lateral incisors.
 In some Cases ,
 both the central and the
lateral incisors are lingualy
inclined and the canines
overlap the lateral incisors on
the labial.

o U – shaped palatal arch
o A deep overbite and minimal
over jet
o with extreme overbite, the incisal
edges of the lower incisors may
contact the soft tissues of the
palate
o In the absence of over jet)
mandibular labial gingiva get
traumatised by lingually inclined
maxillary incisors
Intra-oral
photographic analysis

Lateral cephalometrics
analysis

 Analysis of facial skeleton
 Analysis of mandibular and maxillary base
 Dento alveolar analysis

(N-S-Ar) .
provides an assessment of the relationship
between anterior and posteriolateral
cranial bases
Mean value 123+/-5
Thus a large saddle angle usually signifies a
posterior condylar position and a mandible
That is posteriorly positioned with respect to
cranial base and maxilla
SADDLE ANGLE :

(S-Ar-Go)
Its size depend on position of the
mandible ;
 Angle is Large if mandible is
retrognathic
 Angle is Small if mandible is
prognathic
 Mean value(143+_6)
ARTICULAR ANGLE:

The angle S-N-A expresses the sagittal
relationship between the anterior limit
of the maxillary base and the anterior
cranial base.
Mean value ( 81*)
 It is large in prognathic maxillas
 small in retruded maxillas .
S-N-A angle:

The angle S-N-B expresses the sagittal
relationship between the anterior extent of
the mandibular base and anterior cranial Base
Mean value (79*)
 It is large with a prognathic mandible
 It is small with a retrognathic mandible .
S-N-B angle:

Ricketts drawn from tip of nose to skin pogonion
Normal relation means :
 upper lip is 2-3 mm
 Lower lip 1-2 mm behind this.
Ricketts lip analysis
( E plane)
pog

 Three treatment approaches are available :
1) Growth modification
2) Dental camouflage
3) Orthognathic surgery (with orthodontic treatment)

1) Growth modification for class II skeletal
problem: (Orthopedic treatment)
- The goal of growth modification is to enhance the unacceptable
skeletal relationship by modifying remaining facial growth pattern of
the jaws.
- Optimum timing : Pre-pubertal growth spurt (active growth period)
Two types of orthopedic appliances used in skeletal class II
A) Headgear ( extra-oral force)
B) Functional appliances ( Removable and fixed )

 It delivers an extra-oral orthopedic force to
compress the maxillary sutures and modify the
pattern of bone apposition at these sites.
2 TYPES
Facebow J-Hooks
(maxillary excess ) (Maxillary anterior retraction)
and intrusion

(cervical)
-Distal and extrusive forces on maxillary mollars . (occipital)
-posterior and inferior extra-oral force -Distal and intrusive forces on the maxillary molar
- extra-oral force is directed superior and posterior
-Increases vertical dimension -A-P and Vertical maxillary excess ( decreases V.D)
- used in A-P maxillary excess with flat mand,plane

B- Functional appliances:
Class II functional appliances are designed to position the
mandible in a downward and forward to enhance its
mandibular growth pattern.
 Indication: Mandibular deficiency
Removable Functional: Fixed Functional:
-Activator -Herbst
- Bionator -Jasper jumper
-Twin bloc
- Frankyl II

2) Dental Camouflage:
It is a treatment that seeks to create a dental compensation to hide the
skeletal discrepancy  Maxillary Retroclination and Mandibular Protraction
.
Indicated:
1) Adults
2) Mild to Moderate skeletal Class II cases
3) Minimal dental crowding .
4) Acceptable facial esthetics
5) Usually requires extraction
Dental camouflage without extraction is rare in case of skeletal class II
-Mild skeletal class II cases
- Mild excessive overjet
- Adequate space available
- Max Molar distalization

3) Orthognathic surgery:
A combination of orthodontic therapy and Orthognathic surgery
for the correction of moderate to severe skeletal class II
malocclusion
(Adults, no growth potential)
Indicated:
1) Moderate to Severe skeletal discrepancy
2) Facial imbalances or asymmetries: long lower face , Gummy smile
3) Limitations of tooth movement : Upright on basal bone
4) Relapse potential of orthodontic treatment.
5) Severe crowding and protrusion in the dental arches with skeletal
class II malocclusion (extraction space is not sufficient to correct
buccal occlusion)

 Surgical correction includes:
1) Mandibular Advancment:
Indicated: skeletal class II cases with mandibular deficiency

The intraoral sagittal split ramus osteotomy is the most popular
technique for surgical mandibular advancment.

2) Maxillary Impaction: ( Le Fort 1 maxillary osteotomy )
Indicated: Vertical Maxillary excess
Maxillary Impaction may include 
1)Total maxillary osteotomy ( maxillary excess ant. and post.)
2) Bilateral posterior segmental maxillary osteotomy ( excess
localized posterior)

Vertical maxillary excess in the
anterior and posterior region of
maxilla
 Requires maxillary impaction
by a total maxillary ostoetomy .
To correct the:
1) Gummy smile
2) excessive lower facial height
3) incompetent lips
4) mandible will rotate anti-clock
wise

- Anterior Maxillary sub-apical setback
Indicated: Maxillary excess is in A-P dimension/
Mid-face protrusion ( No vertical excess)
- Combined Surgical approaches :
Indicated: Maxillary excess (vertical or A-P)
combined with mandibular deficiency.

 Moderate class II malocclusions are usually associated
with mandibular deficiency or maxillary excess 
Resulting in a compromised facial esthetics.
 The choice between orthognathic surgery or
orthodontics as a treatment option might be confusing
to the orthodontist in borderline cases.

class 2 malocclusion

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class 2 malocclusion