Transcript FIXED APPLIANCE

FIXED
APPLIANCE
Prepared by
Dr. Hana Omar AL. Balbeesi
Orthodontic consultant
Fixed Appliances :

Are appliances attached to
the teeth surfaces &are
capable to generate a range
of tooth movement more than
RA.

Brackets + Arch wires
{generate force that can move
teeth in three planes of space
vertically , apically &
rotationally }.
Edge Wire
Brackets :
Fixed appliances achieve tooth
movement in 3 spatial planes

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First-order bends. Compensate
tooth widths.
Second-order bends . Achieve
correct angulations or tilt of the
tooth.
Third-order bends . Only for
rectangular arch wires. It exert
bucco-lingual force on the tooth
apex to torque it .
Indications for the use of FA:
1.
2.
3.
Correction of mild to
moderate skeletal
discrepancies.
Intrusion/extrusion of teeth .
Correction of rotations .
4. Overbite reduction .
5. Multiple tooth movement .
6. Closure of extraction spaces ,or
spaces due to hypodontia .
FA
close the spaces +
produce good contact between
teeth.
Patient selection:
1.
2.
3.
4.
Patient maintain good oral
hygiene .
Avoid hard or sticky food .
Cooperative patient .
Attend appointments regularly
to adjust the appliance .
Components of fixed
appliance :
1.
Bands :
a. Seated on molars or any tooth
especially in crossbites .
b. Headgear can be used with them .
c. Separation is a must .
d. Approximate the size in a study
models .
e. The edges should be flushed
with marginal ridges .
f. Bracket in the midpoint of
the clinical crown or 90 % to
the long axis of the tooth .
g. Glass ionomer is used .
2. Bonds :
a. Acid etch and composite is used .
b. Mechanical interlock between
bracket mesh & the composite .
c. They are made of metal or
ceramic .
Disadvantages of Ceramic
Brackets:
1.
2.
3.
4.
Chemical bond between bracket &
enamel surface causing tooth Fx during
debonding .
Brittle they break easily & wings breaks,
so tying of the wire is very difficult .
Hardness of it cause notching of the
arch wire which make sliding of teeth
difficult .
Wearing of opposing teeth not advisable
to be used in the lower incisors .
3. Orthodontic adhesives :
a.
b.
Cementation with glass
ionomer because it can release
fluoride & better affinity to
stainless steal & enamel
surface .
Bonding with composite is
better than glass ionomer .
c. Light-cure or self-cure
acrylic resin .
d. No mix-orthodontic
composite .
e. Despite any material used
excess should be removed .
4. Auxiliaries :
a.
b.
c.
d.
Elastomeric modules are easier to place
& more comfortable to the patient .
Ligatures are better in the late stages of
treatment .
Intra-oral elastics in 2, 3.5, & 4.5 oz
strengths & a variety of sizes 1\8 or 3\4
inches changed every day .
Palatal & lingual arches ,quad helix some
are preformed or made in the laboratory.
5. Arch wires :
Presented in different cross
sectional diameters , &/or
different material construction
a.
b.
Flexible wires in initial stages or
alignment stage .
Rigid wires in the late stages of
treatment .
Arch Wires Physical
Properties :
1.
2.
3.
Spring back : wire returns to
original shape & resist
deformation .
Stiffness : greater diameter
stiffness .
Formability : bending of the
wire to any desirable shape .
4. Resilience : the stored energy
after deflection without
deformities .
5. Biocompatibility .
6. Joinability : if the material can
be soldered or welded .
7. Frictional characteristics: wires
with low surface friction is
preferred .
Types of wires :
1.
2.
Stainless steal : preferred in
later stages of treatment
(multi-strand & or twistflex ).
Nickel titanium : more flexible
, greater resistance to
deformation but expensive .
3. Cobalt chromium (can be
readily formed & R & S
by
heat ).
4. TMA or B-Titanium .
5. They are either round (0.016 =
0.4 mm) or rectangular (0.016
× 0.022 = 0.4 × 0.55 mm, can
be straight or coil in a spool or
preformed .
Treatment planning for
fixed appliances :
1.
2.
Anchorage is important
headgear &/or a palatal or
lingual arch should be placed .
Lower arch form should be
preserved .
Practical procedures :
1.
2.
3.
4.
Pre-adjusted system brackets will be in
the middle of the tooth along the long
axis .
Improper bracket position
incorrect
tooth position,& affect function &
esthetics .
Mesiodistal movement of the teeth can
be achieved by sectional or sliding teeth
along the arch wire .
Patient should be seen every 4-6 weeks.
Fixed Appliance System :
1.
2.
3.
Pre-adjusted appliance or
straight wire appliance
(Andrews’ & Roth systems
are the best) .
Begg appliance .
Tip edge appliance .
Tip edge appliance :
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It combines the advantages of both
Straight Wire & Begg systems .
It allows tipping of the tooth in the
initial stages with round wires &
better tooth positioning in the final
stages with rectangular arch wires .
Decalcification of fixed
appliance :
Fixed appliance
plaque
accumulation
demineralization by 15-85 % .
Approaches to Reduce
Decalcification
1.
2.
3.
Fluoride mouth rinses regularly.
Fluoride containing cements &
bonding adhesives .
Dietary advise chewy sweets,
sugared beverages & fizzy drinks
between meals should be
avoided during treatment .
Starting with Fixed Appliance

Skillful orthodontist :
Knowledge with diagnosis &
treatment planning before
treating any patient .
THANK
YOU