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The Edgewise The Edgewise appliance-evolution & appliance-evolution &
techniquetechnique
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INDIAN DENTAL ACADEMY
Leader in continuing dental education
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Contents :-
Evolution / Historical perspective
1) Bandelette appliance
2) Angle’s E–arch
3) Pin &Tube appliance
4) Ribbon arch appliance
5) Edgewise appliance
Attachments
Modification of edgewise brackets
Evolution of buccal tube
Bracket placement &angulation
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Evolution of the technique -Primary edgewise -Secondary edgewise -Tertiary edgewise Tweed’s philosophy of treatmentGrowth trendsDiagnostic facial triangle Cephalogram or headplate correctionTreatment objectivesAnchorage preparationIdeal arch formThree orders of tooth movementGeneral plan of treatmentMerrifield’s modification
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Evolution of applianceFirst attempt at tooth movement in1728 by a French physician
Pierre Fauchard
Bandalette appliance-crude alignment of teeth by expansion of the dental arches
Disadvantage : lacked stability
no effective means of firmly fixing it in position
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1841-Schange introduced screw force
1849-Dwinelle developed jack screw
1871-Magil introduced dental cements to attach bands on teeth
1866-Kingsley advocated the use of extraoral forces
No attempt was made to correct malocclusion by placing teeth
in a stable soft tissue environment
Angle believed that teeth when moved into their correct
occlusal relationship, stability would be assumed.
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The E arch appliance(1880)
First typical orthodontic fixed appliance
Rigid framework –Molar bands with heavy labial arch wire soldered to them,
Teeth tied to it by means of brass ligature wire
Crown movement & simple anchorage
Teeth were expanded into normal occlusion
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4 different designs:
Basic E-arch Ribbed E-arch E-arch without threaded ends that fit into molar sheaths,
used with an attached ball for high pull head gear in the incisor area
E-arch with hooks for intermaxillary elastics Also had maxillo mandibular growth guidanceDisadvantages :1) correction of axial inclination could not be accomplished 2)long term retention was required
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The Pin &Tube appliance(1912)
Ideal arch of E-arch was not there Arches were altered as tooth
movement carried out progressing towards ideal archform
Bands with tubes soldered on it Pins soldered on the archwire &
made to fit into tube perfectlyChange position of pin ,solder it
again on archwire to a different position & fit into the tube again
Disadvantage:difficult to solder & unsolder pins time consuming
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Ribbon arch appliance (1915)
To overcome disadvantage of pin & tube
Brackets with vertical slot introduced Archwire initially confirmed to
malocclusion ,held in place by brass pins
Rectangular wire with longer dimension vertical
Overcame 2 major problems: 1) archwire placement 2) M-D movement of teeth
Teeth were free to move along the
archwire like strings of beadswww.indiandentalacademy.com
Teeth could tip M-D, even with lockpins
Angle devised cleats to be soldered to archwire to contact the sides of the bracket
Held the teeth upright, but necessitates soldering new cleats at different locations
Disadvantage:-relatively poor root control
-mesial & distal tipping bends could not
be incorporated
-enmass movement of teeth in an antero-
posterior direction was not easy
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The Edgewise appliance(1925)
Solution to all problems –latest & best in orthodontic mechanism
Changed the form of bracket located the slot in the center & placed it in a horizontal plane instead of a verticalBracket wide mesio-distally Rectangular slot for rectangular archwire .022x.028 slot size, same size wire Archwire inserted in narrowest
dimension -EDGEWISE Initially called open face or tie bracketsArchwire held with brass ligature & S-S
ligature later www.indiandentalacademy.com
Types of headgear used
High pull :- intrusion of maxillary incisors increase the lingual root torque used with cl.II elasticsIntermediate pull headgear :- distalise maxillary dentition when bite is not deep hold the maxilla during anchorage preparation Low pull headgear :- open bite case support mandibular dental arch in older patientsThe Kloehn cervical gear :- growth trend is type A or C restricting the maxillary growth so that the mandible can catch up
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ATTACHMENTSEvolution of edgewise
brackets Original bracket – soft gold , .022
x .028 inch slot 1)Single width brackets original bracket .050 inch
wide & soldered to the gold band material
archwire rests on bottom of bracket slot instead of the band
ineffective for tooth rotation because of the narrow width
Angle devised gold eyelets to be soldered on bands
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2)Twin brackets- two brackets on one base -“Siamese twin brackets” by Swain - space between two brackets was .050 inch (equal to width of one
bracket )Main advantage :- ability to effect tooth rotations without using auxiliaries Available in different widths:- Extra wide Standard Intermediate Junior
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3)Curved base twin bracket
curved bases to confirm to the curvatures of the canines & premolars
Advantages of twin brackets :
Offers a positive control
Disadvantages:
increased width decreases the inter bracket span, thus decreasing the resiliency
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4)Lewis bracketDeveloped by Lewis in 1950.To overcome the problem of
efficient tooth rotation.He soldered auxillary rotation
arms that abutted against the bracket itself, thus, offered a lever arm to deflect the archwire & rotate the tooth.
One piece bracket with integral rotation wings
These wings do not interfere with occlusogingival deflections of archwire & do not decrease the interbracket span
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5)Curved base Lewis bracket
Curved base confirms to the canine, premolar surface
Wings lie close to the tooth throughout their length ,so less trapping of food
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6)Vertical slot Lewis bracket Incorporation of .020 x .020 inch vertical slot Possible to use uprighting spring to correct axial inclinations if
neededAdvantages of Lewis brackets: 1) complete rotational control 2)do not reduce the interbracket span
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7) Steiner bracket
Given by Cecil C Steiner in 1931
Incorporated flexible rotation arms & so did not rely on the resiliency of the archwire for tooth rotation
Introduced tie wings for ease of ligation
8)Broussard bracket
Designed by Garford Broussard for use in the Broussard technique
Addition of a 0.0185 x 0.046 inch vertical slot to accept a doubled 0.018 inch auxillary wire
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Evolution of edgewise buccal tube
Original appliance had .022x .028 inch gold or nickel silver tubing soldered to the molar band
Length –3/16 or ¼ inch
Notched distal ends - to facilitate a tie back ligature
Hook – gingival to buccal tubes, soldered on the bands for placement of elastics
Inconel tube - gold buccal tubes were discarded
Stamped buccal tube with welding flanges or
Inconel tube which could be soldered to the band
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Combination buccal tubes Incorporates a round tube for
insertion of a face bow Fairly close tolerances must be
maintained between archwire & tube for effective transmission of torque to the tooth
Triple buccal tube additional rectangular tube for
auxillary sectional & base archwire
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Bracket & tube placement
Angle - “goal of correct bracket & tube placement is to produce an ideal occlusion at the end of treatment with flat, straight, ideal archwires
Tweed advocates – millimeter measurement from bracket slot to the incisal edge
UPPER ARCH LOWER ARCH
Centrals –4.5 Anteriors-4.0Laterals –4.0 Canines-4.5 Canines –5.0 Premolars-5.0Premolars-4.5 Molars-4.0Molars –3.5
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Bracket angulation
Brackets –parallel to the long axis of the tooth
Holdaway (1952) described three uses for bracket angulation
a) as an aid in paralleling roots adjacent to extraction spaces
b) as a method of setting up posterior anchorage units into tipped back or anchorage prepared positions
c) as a means of obtaining correct axial inclinations or artistic positioning
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Evolution of technique� Primary edgewise� � *as described by Angle in 1929� *fully banded technique-gold bands ,soldered soft brackets� *flat ideal arch wire -to provide normal occlusion� *original arch was of .022 X .028 inch gold wire� *to be adapted passively to all malocclusion� *if space had to be made, loops are soldered onto main arch� *if space closure required, spurs & tie backs used� *involves all the teeth to be brought under control so,
treatment should be initiated after eruption of canine & premolar
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� Angle stated that "malocclusion must be treated as though the denture is a self-sustaining, self maintaining unit and all parts of denture exerting or sustaining forces must be perfectly balanced”
� 1) fully normal proximal contact relations of teeth� 2) normal cusp & inclined plane relation � 3) normal upright axial position & relation of teeth � this is essential if the teeth are to balance� with the muscles & sustain the forces of � occlusion
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Angle introduced the bracket 2 yrs. before his death.Proposed nonextraction treatment for all malocclusion Expansion of the dentition – method of teeth alignmentMuscular balance was upset, teeth were moved to an unstable
positions-------high frequency of relapse Little attention to establishment of anchorage
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� Secondary edgewise
� *to avoid the making archwires passive � *use of round wires in the initial stages� *gold was replaced by a more rigid alloy� *frequency of extractions increased� *bands with prewelded brackets � *in 1940s round .045in.tubes were also soldered on � the upper molars for a face bow
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� Tertiary edgewise or Tweed’s edgewise
� *stressed on the importance of anchorage � preparation � *advocated the use of cl. III elastics & extraoral � traction� *vigorous forces were now employed� *space closure was done by simple vertical or � horizontal open loops bent into the archwire or by � push coil tie -backs
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