Mandible looses its posterior proprioceptive and functional support
skeletal open bite
3.management of angles class iii malocclusion
ANGLES CLASS III
What is Angle’s class iii?
• This condition represents a prenomalcy where the mandible is
in a mesial relation to the upper arch
• According to angle, Class iii molar relationship refers to a
condition where the mesiobuccal cusp of the upper 1st molar
occludes between the mandibilar 1st and 2nd molars
• The lower molar can be in the said mesial relationship to
• A straight to concave profile
• Anteriorly divergent profile
• Long face (increased lower face height), which may
be pointed at the chin
• Mandible appears to be well developed (with an
obtuse gonial angle)
• A Class iii molar relationship
• A Class iii canine relationship
• A reverse overjet with possibly labially inclined lower incisors
and lingually inclined upper icisors
• A posterior cross-bite unilateral or bilateral (or functional)
due to a constricted maxillary arch or a more forward
positioned lower arch
i. Short retrognathic maxilla
ii. Long prognahtic mandible
• Hereditary (main factor)
• Functional factors and soft tissues (Flat, low, anteriorly placed
tongue that lies low in the oral cavity / macroglossia)
• Compulsive habit of protruding the mandible
• Unilateral or bilateral hyperplasia of mandibular condyle can
cause the Class III malocclusion.
• Occlusal forces created by the abnormal eruption may
produce unfavorable incisal guidance
• Premature loss of deciduous molars may also cause
mandibular displacement with an occlusal guidance from
• Anteroposterior deficiency of the maxilla can occur in cases of
cleft lip and palate
• Trauma to the mid-face during the growth phase
Correction of class iii
• Growth modification
• Orthodontic correction
• Should be identified and corrected early
• Treatment is highly dependent on the
patient’s age and hence;
A) FRANKEL III APPLIANCE
• Stretches the soft tissue envelop around the maxilla in an
attempt to stimulate the forward growth of the maxilla. Does
not allow the mandible to advance forward.
B) THE CHIN CUP
• Applies forces, directed along the direction of growth of the
condyle. Inhibits the forward growth of the mandible
• Capable of moving the chin down and back.
C) ANTERIOR FACEMASK
• Promotes maxilla to grow anteriorly and/or rotate
downwards. This causes a reciprocal downward and backward
rotation of the mandible.
D) RME WITH ANTERIOR FACEMASK
• RME is used to split the mid-palatal suture causing a
downward and forward movement of the maxilla.
• During this instance the teeth are disoccluded.
• A facemask is used to pull the maxilla further forward.
E) 3-D SCREWS
• Capable of expanding the maxilla in all the three directions.
• Appliances, both removable and cemented can be used to
correct pseudo Class iii malocclusions and thus prevent their
progression to a full-fledged malocclusion.
THE ADOLESCENT CHILD
• Limited to orthodontic camouflage or orthodontic
decompensation in an effort to prepare the patient for
• Camouflage can be achieved by proclining the maxillary
anteriors and tipping the mandibular incisors lingually
• Single arch extractions, extraction only in the mandibular
arch, are frequently done to create space for the retraction of
the mandibular anterior segment
• Emphasis is more on orthognathic surgery.
Bilateral sagittal split osteotomy with retraction of the