History and evolution of edgewise appliance

A VERY GOOD AFTERNOON

Seminar presentation-EVOLUTION OF EDGEWISE APPLIANCE

Under the guidance of : Dr. Mohammad Mushtaq, HOD & GUIDE

By: Sneh Kalgotra,2nd Year P.G.

Department of Orthodontics & Dentofacial Orthopaedics, GDC&H, Srinagar.

Contents

1.Evolution / Historical perspective

1.1Bandelette appliance

1.2 Angle’s E–arch

1.3 Pin &Tube appliance

1.4Ribbon arch appliance

1.5 Edgewise appliance

2.Attachments

2.1 Modification of edgewise brackets

2.2 Evolution of buccal tube

2.3 Bracket placement &angulation

3. Evolution of the technique

3.1Primary edgewise.3.2Secondary edgewise 3.3Tertiary edgewise

4. Merrifield contribuation.

5. References

6. Conclusion.

Introduction

• Edward Angle.

• Charles Tweed.

• Levern Merrifield.

The edgewise arch mechanism was the brain child of this master technician.

Edward Angle, after graduation from dental school in1878 and before his introduction of the Angle System in1888, experienced many technical problems and frustrationsin patient treatment that motivated and inspiredhim to develop a standard appliance.

He believed that an orthodontic appliance must have five properties:

1. Simplicity: It must push, pull, and rotate teeth.

2. Stability: It must be fixed to the teeth.

3. Efficiency: It must be based on Newton’s third law

and anchorage.

4. Delicacy: It must be accepted by the tissues, and it

must not cause inflammation and

soreness.

5. Inconspicuousness: It must be aesthetically

acceptable.

• This was the beginning of a relationship among

manufacturers, suppliers, and orthodontists.

• Angle developed the edgewise appliance from the ribbon arch mechanism and called it the open bracket appliance.

• Because Angle introduced the edgewise bracket only 2 years before he died, he had little time to teach its manipulation, develop it further, and improve its use—and he knew it.

Charles H.

Tweed

When Charles H. Tweed graduated from an improvisedAngle course given by George Hahn in 1928, he was 33 years old and Angle was 73.

Angle decided that an article describing the appliance must be published in Dental Cosmos. He asked Tweedto help him with the article because Tweed had just finished the Angle “course” and because he admired and respected Tweed’s ability.

.

• For the next 2 years the two men worked together closely. Tweed diagnosed, treatment planned and treated his patients, and Angle acted as his advisor. Angle was pleased with the results, and he was instrumental in getting Tweed on several programs.

• During these 2 years, in a series of more than 100 letters, which are now housed in the Tweed Foundation Library, Angle urged his young disciple to carry out two vital requests

• (1) to dedicate his life to the development of the edgewise appliance and

• (2) to make every effort to establish orthodontics as a specialty within the dental profession.

• His untiring and relentless efforts were successful, and in 1929 the Arizona legislature passed the first law limiting the practice of orthodontics to specialists.

• Tweed received Certificate No. 1 in Arizona and became the first certified specialist in orthodontics in the United States.

• In 1932, Tweed published his first article in the Angle Orthodontist. It was titled “Reports of Cases Treated with Edgewise Arch Mechanism.”3 Tweed held to Angle’s firm conviction that one must never extract teeth. This conviction lasted for 4 short years.

• The postreatment facial aesthetics Tweed began to observe in his patients was discouraging to him, so discouraging in fact that he almost gave up orthodontic practice.

• During this 4-year period, he made a most important observation: upright mandibular incisors frequently were related to both posttreatment facial balance and stability of the treated dentition. He selected his failures, extracted four first premolar teeth, and retreated the patients. He did this without charging a fee.

• In 1936 Tweed delivered to the membership of the Angle Society and subsequently published his first paper on the extraction of teeth for orthodontic malocclusion correction. “Mother” Angle, the editor of the Angle Orthodontist and a member of the Angle Society, refused to attend the lecture.

• He worked even harder than before. By 1940, he had produced case reports, with four sets of records, of 100 consecutively treated patients who were first treated with nonextractionand later with extraction.

• Tweed’s many contributions to the specialty established a benchmark in orthodontic thought and treatment. Most notable among his many contributions were the following:

1. He emphasized the four objectives of orthodontic treatment—aesthetics, health, function, and stability—with emphasis and concern for balance and harmony of the lower face.

2. He developed the concept of positioning teeth over basal

bone with emphasis on the mandibular incisors.

3. He made the extraction of teeth for orthodontic correctionacceptable.

4. He enhanced the clinical application of cephalometrics.

5. He developed the diagnostic facial triangle to make cephalometrics a diagnostic tool and a guide in treatment and in the evaluation of treatment results.

6. He developed a concept of orderly treatment procedures and introduced anchorage preparation as a major step in treatment.

7. He developed a fundamentally sound and consistent preorthodontic guidance program that popularizied serial extraction of primary and, later, permanent teeth.

Charles Tweed, one of orthodontics’ most brilliant innovators, kept his promise to his mentor, Edward Hartley Angle. He devoted 42 years of his life, from 1928 until his death on January 11, 1970, to the advancement of the edgewise appliance

Levern Merrifield

• In 1960 Tweed selected one of his most outstanding students, LevernMerrifield, from Ponca City, Oklahoma, to continue his work on the edgewise appliance.

• Merrifield devoted the remaining 45 years of his life to the study of orthodontic diagnosis and the use of the edgewise appliance. Merrifield’s contributions have been disseminated and popularized.

ANGLE’S PHILOSOPHY OF

TREATMENT • Based on the then prevalent assumption that, if

cuspal interdigitation of teeth were made normal, stimulation by function would result in growth of basal bone structures.

• Little or no thought was given to the inclination of the mandibular incisor teeth or to normal mesiodistal relation of teeth and their respective jaw bases and head structures.

• It was assumed that function would take care of such matters.

• Extraction of teeth for orthodontic therapy wasn’t even an option .

Evolution of the appliance

• First 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

• 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 extra oral 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.

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

• 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 pullheag gear in the incisor area.

• E-arch with hooks for intermaxillaryelastics. Also had maxillo mandibular growth guidance

• Disadvantages :1) correction of axial inclination could not be accomplished

2)long term retention was required.

Different types of E- arches.

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 perfectly .Change 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

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 Teethwere free to move along the archwire like strings of beads.

• Teeth could tip M-D, even with lockpinsAngle 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 anteroposterior direction was not easy

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 vertical.

Bracket wide mesio-distally Rectangular slot for rectangular archwire .022x.028 slot size, same size Archwire inserted in narrowest dimension -EDGEWISE .

Initially called open face or tie brackets Archwire held with brass ligature & S-S ligature.

ATTACHMENTS Evolutionof edgewise brackets

Original bracket.

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.

•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

Itermediate

Junior.

3)Curved base twin bracket:

curved bases to confirm to the curvatures of the canines & premolars

• Advantages of twin brackets : Offers a positive control

• 4)Lewis bracket• Developed 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 occlusogingivaldeflections of archwire & do not decrease the interbracket span.

5. Curved base Lewis bracket :

base confirms to the canine, premolar surface Wings lie close to the tooth throughout their length ,so less trapping of food

• 6)Vertical slot Lewis bracket:

Incorporation of .020 x .020 inch vertical slot Possible to use uprighting spring to correct axial inclinations if needed.

Advantages of Lewis brackets:

1) complete rotational control

2)do not reduce the interbracket span

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.

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 .

• 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 auxillarysectional & base archwire.

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 Centrals –4.5Laterals –4.0 Canines –5.0 Premolars-4.5 Molars –3.5

LOWER ARCH Anteriors-4.0 Canines-4.5 Premolars-5.0 Molars-4.0

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.

At the end of the treatment.

Armamentratium

PLACEMENT OF SEPARATORS

After placement of band and

bracket.

Archwires

• The dimensions (in inches) of the wire commonly used are 0.017 × 0.022, 0.018 ×0.025, 0.019 × 0.025, 0.020 × 0.025, and 0.0215 ×0.028.

• These wire dimensions give a great range of versatility with the 0.022 × 0.028 bracket slot and allow the sequential application of forces as needed for various treatment objectives. The objective is to enhance tooth movement and control with the proper edgewise archwire at the appropriate time.

Torquing plier

Ligature forming plier Ligature locking and tying plier

Arch-bending plier Nance loop formerNance diagonal spur forming plier

Tying of the liagture.

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 .

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.

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.

Tertiary edgewise or Tweed’s

edgewise

Stressed on the importance of anchorage preparatio,. advocated the use of class III elastics & extraoral traction vigorous forces were now employed.

Space closure was done by simple vertical or horizontal open loops bent into the archwireor by push coil tie .

MERRIFIELD MODIFICATION.

• Diagnostic Concepts.

• Treatment Concepts.

Diagnostic Concepts.

1. The fundamental concept of dimensions of the

Dentition.

2. Dimensions of the lower face.

3. Total space analysis.

4. Guidelines for space management decisions to achieve

the following:

a. Maximum orthodontic correction

b. Define areas of skeletal, facial, and dental disharmony.

Treatment Concepts.

5. Directional force control during treatment15

6. Sequential tooth movement

7. Sequential mandibular anchorage preparation16

8. The organization of treatment into four orderly steps that have specific objectives.

Variations of the Appliance

Many variations of the edgewise appliance

have been introduced in the past 30 years.

• Most notable of the variations is the “straight wire” appliance introduced in 1972 by Larry Andrews.

• Another variation is a decrease in slot size from 0.022 to 0.018 inch and even to 0.016 inch.

• Other modifications have been extensively described by Burstone, Lindquist,

Roth.

Conclusion

Angle gave orthodontics the edgewise bracket, but Tweed gave the specialty the appliance. Tweed was considered the premier edgewise orthodontist of his day.

Many who admired his results wished to learn his techniques.

The Tweed Philosophy was born.

In summary, Tweed's basic concepts were:

(1) a deep and abiding interest in facial esthetics;

(2) Carefully planned extractions to achieve a predetermined objective. To arrive at the predetermined objective, Tweed had to define the anterior limits of the dentition. He developed the diagnostic facial triangle for this purpose;

(3) precision appliance adjustment; and

(4) en masse anchorage preparation.

The orthodontic world beat a path to his door in Tucson. Tweed, the innovative and perceptive diagnostician and master clinician, kept his promise to his mentor, Edward Angle.

He devoted all 42 years of his professsional life to the use and refinement of Angle's invention, the edgewise appliance.

Tweed's last great work, the two volume

Clinical Orthodontics, is inscribed

"To Dr. EdwardHartley Angle, a dynamic psychologist with the power to mold the character of men; to his devoted wife, Anna Hopkins (Mother) Angle,who guided his career and bathed the wounds of those undergoing his molding procedures; …………….. “

References

1.Angle EH. The malocclusion of the teeth. Philadelphia, PA: SS White Co, 1907:21-24.

2. Personal letter from Glen Terwilliger to Jack Cross, June 30, 1977.

3. Tweed CH. A philosophy of orthodontic treatment. AmJ

4. Tweed CH. The Frankfort-Mandibular incisor angle (FMIA) in orthodontic diagnosis, treatment planning and prognosis. AmJ Orthod Oral Surg 1954;24:126-169.

5. Tweed CH. Clinical Orthodontics. vols I and II. St. Louis, MO: Mosby, 1966.

7. Tweed CH. A philosophy of orthodontic treatment. Am J Orthod Oral Surg. 1945;31:74.8. Tweed CH. Indications for the extraction of teeth in orthodontic procedures. Am J Orthod Oral Surg. 1944;30: 405.9. Tweed CH. The Frankfort mandibular incisor angle (FMIA) in orthodontic diagnosis, treatment planning and prognosis. Am J Orthod Oral Surg. 1954;24:121.10. Tweed CH. Clinical orthodontics. Vols 1 and 2. St Louis: Mosby; 1966.11. Merrifield LL. The dimensions of the denture: back to basics. Am J Orthod Dentofac Orthop. 1994;106:535.12. Merrifield LL. The profile line as an aid in critically evaluating facial esthetics. Am J Orthod. 1966;11:804.13. Merrifield LL. Differential diagnosis with total space analysis. J Charles H Tweed Int Found. 1978;6:10.14. Merrifield LL. Identification and classification of orthodontic and orthognathic disharmonies, unpublished lecture. Rio de Janeiro: Brazilian Society of Orthodontics; Nov 20, 1997.15. Merrifield LL, Cross JJ. Directional force. Am J Orthod. 1970;57:435.16. Merrifield LL. The systems of directional force. J Charles H Tweed IntFound. 1982;10:15.17. Merrifield LL. Differential diagnosis. Semin Orthod. 1996; 2:241.

18. Merrifield LL, Klontz HA, Vaden JL. Differential diagnosticanalysis systems. Am J Orthod Dentofac Orthop. 1994;106:641.19. Bishara SE, Hession TJ, Peterson LC. Longitudinal soft tissueprofile changes. Am J Orthod. 1985;88:209.20. Burstone CJ. The integumental contour and extension patterns.Angle Orthod. 1950;29:93.21. Burstone CJ. Lip posture and its significance in treatmentplanning. Am J Orthod. 1967;53:262.22. Johnston L. Nothing personal, Newsletter of the Great LakesAssociation of Orthodontists. 1997;33:3.23. Horn A. Facial height index. Am J Orthod Dentofac Orthop.1992;102(2):180.24. Radziminski G. The control of horizontal planes inClass II treatment. J Charles H Tweed Int Found. 1987;15:125.25. Gebeck TR, Merrifield LL. Orthodontic diagnosis and treatmentanalysis: concepts and values, part I. Am J OrthodDentofac Orthop. 1995;107(4):434.

Thank

you.

-BySneh Kalgotra2nd year P.G.