Management of cross bite /certified fixed orthodontic courses by Indian dental academy

MANAGEMENT OF CROSS
BITES

www.indiandentalacdemy.com

INDIAN DENTAL ACADEMY
Leader in continuing dental education
www.indiandentalacademy.com


Introduction
• Crossbites are term used to describe
abnormal occlusion in transverse plane. The
term is also used to describe reverse overjet
of one or more anterior teeth.


Definition
• GRABER has defined cross bites as a
condition where one or more teeth may be
abnormally malposed buccally or lingually
or labially with reference to opposing tooth
or teeth.


Classification.
• Based on their location as:
Anterior :single tooth or segmental
Posterior:unilateral or bilateral
• Based on the nature of the cross bites
Skeletal
Dental
Functional

Etiology
• Persistance of a deciduous tooth
• Crowding or abnormal displacement of one
or more teeth
• Retarded development of maxilla in sagittal
as well as traneverse direction
• Narrow upper arch
• Collapse of the upper arch
• Unilateral hypo or hyper plastic growth of
any jaws

Contd
• Sagittal discrepancies of the jaws such as
forwardly positioned mandible.
• Presence of habits such as thumb sucking
and mouth breathing can cause lowered
tongue position.


Classification by the
characteristics of mal occlusion
• Evaluation of facial proportion &esthetics
• Evaluation of allignment &symmetry
• Evaluation of skeletal&dental relationship
in the transverse plane of space.
• Evaluation of skeletal&dental in the
anterior plane of space


Management
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Management of dental cross bite
management of skeletal cross bite
DENTAL CROSS BITE management in
primary dentition
early mixed dentition
late mixed dentition
permanentdentition

Management
• SKELETAL COSS BITE management in
• pre adolescent children-primary &early
mixed dentition. 2.Palatal expansion in late
mixed dentition
• Adults
• SURGICAL correction


Management in the primary
dentition
• Anterior cross bite: removing the
interferences by occlusal grinding or
extracting the primary incisor.
• Posterior cross bite: if the inter molar width
is satisfactory, grinding primary canines to
eliminate deflective contact. If both molar
&canine width are narrow, expansion of the
upper arch is indicated.

Early mixed dentition period
• ACB: Lingually trapped inciors can be
corrected by extracting the adjacent canines
if sufficient space is not available. If
sufficient space is available a maxillary
removable appliance is usually the best
mechanism to correct a simple anterior
cross bite that requires tipping movement.

contd
• PCB: Both removable & fixed appliance is
used. The maxillary arch should be over
expanded and then held passively in this
over expanded position for approximately
3months before it is removed.


Contd
• 3 basic approaches to the treatment of PCB
in children
• equilibration to eliminate mandibular shift
• expansion of the constricted maxillary arch
• re positioning of individual teeth to deal
with intra arch asymmetries.


History of expansion appliance
• 1875 Coffin found the coffin spring
• 1902 Pierre Robin introduced jack screw
• 1924 maxillary crozat appliance by HC
Pollack
• 1947 Rickets introduced the quad helix
• 1960 RPE by Angell
• 1993 nickel titanium palatal expander
byWendell.v .Ardnt

COFFIN SPRING
• Made of 1.25 mm SS wire
• differential expansion in molar & pre molar
regions.
• Disadvantages: unstable ,lack control in the
molars,frequent activation needed , force
applied varies.


W- Arch
• Constructed of 36 mil steel wire soldered to
molar bands
• move both primary &permanent teeth
&accelerate the rate of normal expansion of
the mid palatal suture.
• Activated by simply opening the apices of
W
• Expansion should continue at the rate of
2mm per month

Quad helix
• Constructed with 38 mil steel wire
• Helices in the anterior plate helps in
stopping a sucking habit.
• Indicated for the correction of crossbite &
finger sucking habit.
• Forces are produced when the appliance is
widened by 3to 8 mm
• 3 months of retention is recommended

Indications
• Crossbites in which upper arch need to be
widened
• thumb sucking or tongue thrusting cases
• cleft palate conditions either unilateral or
bilateral
• cases of class 2 & class 3 conditions in
which the upper arch need to be widened.

Disadvantages
• Excessive tipping of teeth buccally
• movement are not long enough & hence not
retained long enough.
• Restriction of tongue space so tongue
function is hampered
• intermittent forces
• frequent activations are required
• uncomfortablewww.indiandentalacdemy.com
for patient

Cross elastics
• Typically run from lingual of upper molar
to buccal of lower . For scissors bite
opposite is followed.
• Indicated for a short period to correct
simple cross bite
• effective in correction of unilateral cross
bites.

NITI palatal expander
• It is a tandem loop ,temperature activated
palatal expander.
• Apply light continuous pressure on the mid
palatal suture.
• Self activated
• action is due to niti’s shape memory
&transition temperature effects

Advantages
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Little clinical manipulation
absence of lab work
reduced treatment time
exerts light continuous forces
requires no adjustments
comfortable & minimal patient co operation
it has a safety system &helps the patient to
mitigate the pressure response

ELSAA
• Expansion & Labial Segment Alignment
Appliance
• used for the purpose of expansion and labial
segment alignment prior to treatment by
functional appliance
• until 4-6 months into the functional
treatment ,the previous ELSAA must be
worn when ever the functional appliance is
out of mouth. www.indiandentalacdemy.com

Eccentric screws
• For fanwise maxillary expansion
• Consists of two parts - hinge & special
screw
• Types 1. Wipla expansoion screw
2. G mullers anterior & posterior fan wise
expansion
3. Screws meantwww.indiandentalacdemy.com single teeth
for pressure on

Disadvantages
• Only outward tipping of teeth
• patient cooperation is essential
• force levels decline especially if patient is
not activating properly


Hybrid expanders
• Hilger’s palatal expander- James .J.Hilger1991
• rigid midpalatal dysjunction ( nance button
& screw) with flexible( Quad helix)
alveolar tipping type of appliance.


Slow expansion screw
• Introduced by FARRAR
• Piere robin introduced the jack screw & was
incorporated by A.M Schwartz in 1930
• equal division of the plates will provide
reciprocal anchorage
• screw when turned 90degre will drive the
parts of the plate apart by .2mm

Types of screws
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240 types are available
some of them are ; 1. Wiese screws
2.Pullscrew
3. HAUSER spring action screw
4.3d screw of Bertoni


Magnetic expansion
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Types ;Platinum cobalt
Al-Ni-Co
Ferrite
Cr-Co- Fe
Samarium Cobalt
Neodymium-Iron-boron

contd
• Studies were conducted by Vardimon et al
on female macaca facicularis monkeys
• magnetic expansion from tooth banded or
pallatally pinned appliance delivered ideal
forces compared to jack screw appliance
• Daredilier et al used mid palatal repelling
magnets expansion device to produce both
dental &skeletal changes

Advantage
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Minimum patient cooperation
less pain &discomfort
continuous force exerted
treatment time reduced
less periodontal disturbances,root resorption
&caries
• no friction

contd
• Less chair side time
• better force
• better directional force control


Disadvantage
• Suffer tarnish &corrosion which is
cytotoxic
• cost
• bitterness.
• Bulk of magnet in space limiting
application
• bio effects of static magnetic field

Management in late mixed
dentition period
• ACB- best method for tipping maxillary &
mandibular teeth out of cross bite is using
finger spring, double helical cantilever ,Z
spring along with an anterior bite plate to
prevent any hindrance to tooth movement
• Fixed appliances are also used for the
correction. Eg maxillary lingual arch with
finger springs.Use of posterior bands
&anterior bonded attachments with a round

Skeletal cross bite correction in
Pre-Adolescent children
• Corrected by opening the mid palatal suture
• Growth at this suture continues in most
children until late teens & then ceases
• less force is required to open the suture in
primary &early mixed dentition period
• W-ARCH ,Quad Helix & Jack screw
appliance are used .They deliver less than 2
pounds of force.

contd
• A fixed banded or bonded jack screw appl
can be used.
• Advantages ; 1. One can apply heavy force
if needed. 2.Extinguish habit by the virtue
of appliance bulk. 3.Control vertical growth
and posterior eruption if the occlusal
surface are with bite blocks

Functional Appliance
• These appliance incorporate some
components to expand the maxillary
arch,either intrinsic force-generating
mechanism like springs & jack screws or
buccal sheilds to relieve buccal soft tissue
pressure.


Expansion in late mixed dentition
• As age increases, the sutures becomes more
& more tightly interdigitated and opening it
becomes eventually difficult.Avery heavy
force is required to open the suture.10 - 20
pounds of pressure.
• A fixed appliance is required because the
force magnitude is large enough to displace
removable appliance.

Rapid Palatal Expander
• It involves appliance activation of at least
0.5 mm daily
• The force is transmitted immediately to the
teeth & then to the suture.
• 10 -20 pounds of pressure is applied
• the expansion occurs faster & to a greater
extent in the anterior portion of the palate
because of the buttressing effect of the other
maxillary structures in the posterior region.

A P MAXILLARY
DEFICIENCY
• Children under the age of 8 this treatment
can be accompolished with a face mask that
obtains anchorage from the forehead and
chin &exerts force on the maxilla via
elastics that attach to maxillary splint
producing tooth movement and
displacement of the maxilla
• in older children above 9 this produces
dental movement &very little skeletal

contd
• Approximately 12 ounces of force is
applied for 14 hours per day
• elastics should be fastened to the splint
between the canine &primary first molar
area
• Ideal patient are: normally positioned or
retrusive incisors,but not protrusive.Normal
or short, but not long, anterior facial vertical
dimensions www.indiandentalacdemy.com

Mandibular Excess
• Extra oral force applied via chin cup
restrain excessive growth of the mandible
• Two ways to use chin cup :
• First is to apply force on a line directly
through the mandibular condyle
• Second is to orient the line of force
application below the mandibular condyle

Ideal patient for chin cup
treatment
• A mild skeletal problem, with the ability to
bring the incisors end to end or nearly so
• short vertical face height
• normally positioned or protrusive ,but
retrusive lower incisors


Combined surgical & orthodontic
treatment
• For patients whose orthodontic problems
are so severe that neither growth
modification nor camouflage offers a
solution surgical realignment of the jaws or
repositioning of the dento -alveolar
segments is the only possible treatment.


Indications
• Some problems that could have been treated
with orthodontics alone in children become
surgical problem in adults
• Conditions that intially look less severe for
eg.5mm reverse over jet, can be seen even
at an early age to require surgery


Conclusion
• Diagnosis is the golden key to success. A
case of cross bite can be deceptive . So,it is
always mandatory to think before we leap
into conclusion, whether it is cross bite of a
true nature or pseudo. To achieve better
treatment finish,crossbites should be dealt
as soon as detected & the choice of
armamentarium can be left to clinicians
discretion

Thank you
www.indiandentalacademy.com
Leader in continuing dental education


Management of cross bite /certified fixed orthodontic courses by Indian dental academy

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