Light Archwire Technique

8/10/2019 Light Archwire Technique

1/19

I. li. Ihcx:, l).l).s(:.(Au~:I,.), l,.l~.S.(VIC.), H.I~.S(:.(JI~:r,tl.),

hEL;\II)E. ~OIJTH ~~IlSTR.ZLI .~

T

HIS article descrilxs the light arch wircl tc~chniquc and some minor changes

that have been made in it recently.

The tjechniquc has crolvcd after manly pars cspcricncc with the edgewise

techniqnc. It, neither cont,radicts nor sacrifices any of the principles of the

edgewise technique.

r shall oxplain the technique mainly 1)~ giving

tlctails 01 I rcatfnc~nt, of a

l)atiellt. with a severe Class IT, Division 1 malocclusion. There will also he

brief descriptions of treatment of other pal iciits. Beforc~ treat,mcnt of pa-

tients is tlescrilxxl, however, the \-arious arc~h wires, bant ls, i1lld ausilianics

will he portrapcd and some of the principles of diffcrcliitial force will he de-

sc+l)ed. It. will then be easier to ~uid~~~~tand he descriptions ot treatment t,liat

ill% t0 fOllOW.

Fig. 1 shows a plain arch wire with intermaxillary hooks.

The slight bends

iii the anterior region of this arch wire wcrc made to overmovc slightly irregu-

lar teeth beyond regular alignment. ()~.eialo~c~rnc,rlt of rotaM teeth is an cs-

ccllent form of retention, for the tchcth a~ less likel,v to mov( Ijack any more

than to regular alignment after treatment. .\rch wires are made of speciall .

treated round, resilient, stainless steel wire; usually the)- are 0.016 inch in dian-

cter

but

sometimes the)- are smallc~~.

bigs. 2, 3, and 4 portray* arch wilaes with vertical espalGotl Loomis.

This

looped form of arch wire is used at the start, of treatment to n~akr sl)acc fur

and to align teeth that are so irregular,

crowded, and rot,ated that th(y eantloi

he aligned easily by plain arch wires. \Fhcn there is only slight or no crowtl-

ing, however, there is no need to make thcsc loops in the arc~h wires.

l,oopecl

arch wires irra,v also l)(l aclivatc~d to 1~10~0 pacetl tee111 ogether.

Fig. 5 shows an auxiliar)- arcll wire with \Wticill spurs or I)ro.jwtio~ls for

torquciiig tooth roots lingually-. lahiallv. or lniccally.

Presented at the annual meeting of tlrc .\nwri(an A\ssociation of Ortl~~~tlonti sts in Wash-

ington, n. C., April 28, 1960.


2/19

1.

ITorizontal band spurs are shown in Fig. 8. These spurs, at,tached to the

hands mesial or distal to the brackets, arc for torqueing tooth roots mesiall,v

or distally.

It will have been observctl that IJr. Xdward IT. Angles rihhon arch

bracket is used. Its dimensions have hcen altered to tit light arch wire.

SOME CHARACTERISTICS OF THE TECHiVIQUE

All tooth movements--bodily, torqueing, tipping, and rotating-can he

performed.

All forms of rn;llocclusion are treated wit,h this tcchniquc.

Fig. (i shows all arc11 \viro will]

\'t'l*ti(*ill

sl)urs of slightly tlilllcretrt tlcsign.

The sl)~u+son thwc auxiliary arch wiws project;

gingivally wlir~r the roots have

to Ix 1i10vr~t1 lingttally, and towarcl the ocalusal plane when t hc roots have to

he movctl labia I Iy. On the Icft side of Fig. 7, cyelcts are port,rayed. These

arc used with ligature wires to torque tooth roots mesially or distally.

A

torqncing

wire is shown on the right side of Fig.

7. Torqueing wires move

teeth to their correct, mesiodistal axial relations without having to he re-

ilctivatrtl.

Wig. 6.


3/19

Wig. 8.

The principle of difterential force will now he explained briefly. In this

technique, advantage is taken of the principl(L that, for moving teeth with a

small root-surface area relatively light arch wire and rubher ligature forces

produce the most rapid movement with the lcast disturbance to tooth-investingy

tissues.

These light, forces leave the larger-rooted posterior anchor teeth almost

stationary.

(lonversely, relatively large forcts ~austr the anterior teeth to resist

t ho pressure.

Therefore the anterior teeth t~~ovc very slowly, so that they,

paradoxically, can be made to act as anc~ho~~

WI 11 while the posterior ieeth--

the so-called anchor teeth-move rapidly.

When this differential force prirwiplc is applied to treatment, there is no

difficulty in moving post,erior teeth mesiall?

int)o first premolar extraction

spaces, or

in moving anterior teeth hack into these spaces, according to the

requirement of each patient.

Of course, an intermediate force simultaneously


4/19

\ du111L 4i

l,~(:Hl .\WH ISIKE TE(IINIQl I:

Ullrnlwr I

33

~noves the posterior anchor teeth mesially and the anterior teeth distally. The

principles of differential force have been previously described in more detai1.l

When differential force is used in non-extraction cases, anterior teeth can

be moved back onto basal bone. This is done by taking advantage of the

spaces between teeth. With differential force, the positions of posterior teeth

can he controlled more successfully than with techniques that employ heavier

forces.

As the posterior teeth can be prevented from moving too far mesiall>-,

I hc purpose of orthodontic tooth extraction is not defeated.

Another example of the application of differential force is it,s routine

use

for

reducing deep anterior overbite by the force from tip-back bends in thr

arch wires, usually placed immediately distal to the bracket on t,he band of the

second premolar. The arch wire force from these tip-bark bends is so light

that the molars are neither tipped back nor elevated in their sockets, but the

force is of the appropriateIF low

value to

depress upper and lower anteriol

t cleth in their sockct,s.

Furthermore, owing to the use of opt,imum arch wire and rubber ligature

forces throughout treatment, it, is possib le to keep all teeth moving-- from start,

to finish of treatment -by direct paths from their original positions to their

corrected occlusion.

Teeth are kept moving toward their posttreatment

positions without the interruption of having their movement reversed b>

(llass TII intermaxillary elastics in preparation for mandibular anchor age t 0

rrsist force from Class II intermaxillary elastics.

It is also unnrcessar>- to

rise removable appliances, before or during act,& treatment, to aid the arch

wires in moving the teeth. This is because with light arch wires it is easy to

conduct tooth movements without causing undue movements of anchor teeth.

Round, instead of rectangular, arch wire is used chicfly hause it allows

simple tipping of teeth. It is also used because rectangular arch wire would

have to he so small to deliver the light forces nccdcd for this technique that

it. would slip ar ound (cvcn in the most tight-fittin

g braclrrts) when activated

to torque tooth roots.

Then no torque force would 1~ deliveretl.

The sequence in the stages of treatmrnt differs from that of the cdgewisc

technique. This is

hecause

tooth-moving Iorce vwlncs can

lw

increased or tie-

creased

ilS

mpiircd.

~rlum~rnmxw Olp .\N II~l~USTK.\TIVb: ('.\Sl*:

The following case was chosen for presentation because the plan of treat-

mcnt, is typical for this light arch wire technique.

The patient had a Class II, Division 1 malocclusion complicated by pro-

nounced tooth crowding and himaxillary protrusion (Figs. 9 and 10). Figs.

11 and 12 show the patient after treatment.

Fig. 13 shows the occlusion when it was impossible for any of the four

lower premolars to erupt because of lack of space. The lower second permanent

molars could not erupt, since they were impacted almost horizontally. There-

fore, at this time the four permanent first molars were extracted to allow

eruption of t.hc n1,per and lower first and second premolars and the permanent

second molars.


5/19

i


6/19

This patient, had the most severe Class II, Division 1 condition that I have

seen. The lower right canine occluded distall,v to the upper right first premolar.

On the left side, the occlnsal malrclatiorls were almost as severe.

The four first premolars were cstracted just before active treatment was

started. It is only when patients havc~

the most marked tooth-hone clis-

crepancy that eight teeth are cstractcd.

Such pronounced discrcpancirs arc

estimated to comprise about 3 p01

cent of cases requiring tooth cstradion.

Gt?ner~illl~-, only the four first pre-

molars are cstractcd.

Treatment of Class II and (:lass I malocclusions is divided into three

stagw, as, of course, was the trcai-merit> of this piltiVIlt.

Fig. 1.5

First Stcqe (I% /. 16).-Plain upper and lower arch wires were applied

at the start of treatment,. Iligature wires, tied loosely around the distal s ides

of the canine brackets and the intcrmasillary hooks, prevented the six upper

ant1 lower anterior teeth from moving apart. The four permanent wc~ontl

molars wcrc the anchor molars.

Of course, in all hut a few patients, the permaiieiit~ first molars arc not

cstracted.

The- arc then the illl(ahor tecxth and the second permanent molars

arc not, handed.

During l.Iiis first, stage 01 1 cat meni, llrc Iollowing t.ootlr niovwients wcw

carried out, sitnultaneousI\- :

(1 ) The slightli- irwgular ltppcr and lower

anterior teeth were alignetl.

[l) The tlecp anterior overbite was clirninatcd.

(3) The anteroposterior occlnsal malrelations were corrected.

(1) The dental


7/19

arches were tuade to assutue good cotitours.

( 5) The spaces created by es-

Iraction of the four first prcmolars wvre reduced itt size but ttol. half c~loscvl.

(6) Premolar Yotations were overc~oi~rc~tctl.

These toot,11 ttiovetiietits of the first stage of t tvattiietit w(Lre cat2iecl out itr

the following mariner :

Slight bends were made in the anterior segtuetits ot

both upper and low-et* l)laiti at~lt I\-irks to citusc o~c~~co~~ect;iolr0 1 the slightly.

irregular incisors. Sleep tip-back Ixv~tls. l)lac:etl some distance ttiesial to thr

Wig. 17

Fig. 19

molar tubes at the start of tmtttrtetrt itt l)otlt ttpltcr

illltl

lower arch witacs, dC-

pressed tltc six upper and loM.tlt. atttct*ior teeth gitigivally and t ttct*eby elittri-

ttated the tlevp atttetk overbitt>.

.2lso, at t tie start OF treattttettt, a (lass I1

ititerniasillary elastic was applied 011 eac*lt sitlc.

F&h elastic esert,ed a force

of between 60 and 70 grams.

Thcreforcl, the deep irtciso~ overbite, the ovcrjet.

aud the Class 11 occlusal malrelat ions wcrc l)cirig c~orrc~ctcd sitttultartcoitsl~-.


8/19

As the operations of eliminatin,

0 the anterior overbite and of correcting

anteroposterior occlusal malrelations were performed simultaneously, each opera-

tion benefited from the reciprocal interplay of the tooth-moving forces. If the two

operations of eliminating the deep anterior overbite by means of the tip-back

l)ends in the arch wires and of correcting the Class II occlusal relations of the

ic~rth by (lass II elastics arc not pcrformcd simultaneously, neither of the two

operations can be successfullS accomplished, for the following reason :

Class

I I elastics could then not, tip the upper anterior teeth back beyond the point

where they would strike the lower anterior teeth. This striking would Cause

the lower molars to be moved mesially by the (lass II elastics. Also, the

anterior bitcl opcaning, brought about. by the tip-back bends in the arch wires.

would collapse unless maintained by t,he edgeto-edge occlusal relations of the

incisors that had bcctn attained with the Class II elastics.

\Vc will now continue with the description of the paGents treatment.

The

(Ilass Il. elastics were tippin g back the six upper anterior teeth simultaneously,

hut the upper posterior teeth were not bein

g moved distally by the Class II

chlastics l~causc the distal ~~1s of the arch wire were able to slide back freol?

tlllmgll t11c I~rol;ll~ t111,cs.

Thercforc, the upper extraction spaces bccamc

snialler.

At the same time, the distal ends of the lower arch wire were sliding back

freely through the lower molar tubes, so that the lower extraction spaccs ww

l)ecomin~

slnaller-not because the lower posterior teeth were ljeing

n~orrd

mesially to an\- appreciable extent by the Class II elastics

hut hcause

the six

lower anterior tcct,h were being tipped back onto basal bone.

There

has hn

no satisfactory explanation, so far as I am an-are, for this

tipping-back of ihe lower anterior teeth when no deliberate attempt is being

made to close the lomcr (Mraction spaces.

Fig. 17 shows the condition at the end of the first stage of treatment. At

this stage (lass II occlusal relations are always purposely overcorrectcd until

the molars almost reach (lass III relations and until the incisors are in edge-to-

edge relations. This occlusion is maintained throughout treatment

1)~ ('lass

IT

elastics until just

lwfore

active treatment is finished.

Secontl Stcr~~eof Il~~~~nf~)~r~zt.--The nly purpose of

the second stage is to

complete the closure of the extraction spaces.

In each of the four buccal seg-

m(lnts, an elastic is hooked over the distal free end of the arch wire. It is

brought

forward and hooked onto the intermaxillary hook to close the extraction space.

Treatment is certain to fail if horizontal space-closing elastics are worn during

the first stage of treatment.

The only exception t,o this rule will he mentioned

later.

Space-closing elastics are identical in size and strength with those used

for intcrmasillar>- &sties.

The

six upper and lower anterior tecbth were not

moved

hack

botlil~-

hut

were sittlply I-ippetl back s ilnultanc~oL~sl~- IO close the

estrartioii spac*es.

\Vhilc the extraction spacaes were being calosed, (Ilass 11

intermasillary elastics also had to

be

worn

11s

this patient, as

by all Class II

patients, to maintain the previously ovcrcorrected anteroposterior occlusal

relations of the teeth.


9/19

38

REGG

Fig. 18 shows the condition at, the end of the second stage of treatment.

The appearance of the paCent at this sta.ge was far from plcasing. Only in

patients w&h marked bimaxillary protrusion does the backward tipping r)t

upper and lower anterior teeth become as pronounced as it was in this patient.

The crowns of anterior teeth are allow4 to tip back insttvltl of being

moved back bodily hccause their bodily movclment, would so strain the molar

anchorage that the molars would be moved too filr mcsiaIl~-.

Those learning to use this techniqnc arc Iikcly to become so alal~nrt~l 1)~

the

unpleasant appearance of their patients ilt this st,agc that they mu;- he afraid

to continue and may therefore girt

UJ) i1l thr lllitltllc ot treattllerlt. ~hweforc.

all stages of treatment. carried out 1)~ casperic>ncvd operators, should 1)~ ol~~\rtl

by those who intend IO start IAng this tcvhniclnc. Also. I)ctore starting to Iis0

this technique, the or~tliodontisl. Sho11ld Iilk? il coinprehensivc coII1sc of in-

struction in its use.

Fig. 20.

.1Sstraction sl)aces arc not

~~Iosf~d

until iI lter ( lass 11 elastics have cot-

rected anteropostrrior occlnsal relations, for this ensures that the Class ZI

elastics will not move the lower anterior tooth lahialIy off basal bone. In othcl

words, thcl extraction spaces act 21s saft+y valves to prevellt mandibular

anchorage failure.

Third Stage of Treatment

(air].

I )).-The third and final stage of treat-

ment is designed to put all teeth into

good asial relations, that is, to upright

all teeth. At, the beginnin,

0~of this stage,

nppel*

and lower auxiliary arch wires

containing vertical spurs were applied

gingivallv to the original arch wires.

Thus, the patient simultaneousl>

wore four arch wires-two upper and

two lower. The vertical spurs, leaning

against the four upper and lowel

incisors, were act,ivated to torque the roots of these teeth lingually.

Also.

at. the beginning

of this third

st,agc, the IlOlhlltill

band spufs at th?

Illesiogill#ivill

angles 01 all Ilre sccv~ncl )rc~moI;~i~s vflrv Ilscvl lo

lllovc the CLOWIIS

of these letltlr distally.

~11 tllC

Silltlt

i imc I)I(h

wiliilv IY~OIS \VPl(

lil)lWl l)il.(k

by the springs portrayed in Fig. 7.

From Fig. 20 it. may be seen that, the roots of the canine and the s~on~l

premolar are paralleled. Turin g this third stage of treatment the mesiodistal


10/19

ilXial rclatims of the incisors wc~re c~~rrc~c~it~~l, wlIerc n~wssary , l)y thrca~lin~

ligatllrc wires through the eyc1ct.s anti extending

t hew ligatures around the

arch wires and periodically tightenin,

1~ he ligatures as shown in Fig. 7.

To prevent the extraction spaces from opening, the buccal segments were

tied back with ligature wires extendin,

(7 around behind the molar tubes to the

intermaxillary hooks.

Fig.

21 shows the appliances in position at the end of active treatment.

(%LSS TI elastics had to be worn during this third stage of treatment, since

whenever they were left off there were signs that the orercorrccted antcro-

posterior occlusal relations would not otherwise be fully maintained.

Active treatment time was twenty-one months. For the first third of the

treatment period, disappointingly slow progress was made because the patient

was unable to keep appointments regularly. An upper Ilawley retainer was

worn for six and one half months. So lower retention appliance was worn.

Fig. 21

The final models, already portrayed in Figs. I-l and 15, represent thcl

condition twenty-three months after the end of the retention period.

When first. permanent molars are used for anchorage, small round molar

tubes are used and the distal ends of the arch wires are not doubl ed back as

the - were for this patient.

The Use of Nnrrow Zjjacliet.V.--Thc chief reason for using such

m&o-

distally narrow brackets as the ribbon arch bracket is to allow simple tipping ot

the crowns of the teeth to take place mcsially or distally until the third stage of

treatment is begun. Brackets that arc wide mesiodistally should never be used

for this technique, for if anterior t,eeth are held rigidly to the arch mire in the

mesiodistal direction during the first and second stages of treatment mesial and

distal movements of the roots of anterior teeth cannot be avoided. In other

words, simple mcsial and distal

tippin

g of the crowns of these teeth cannot

take place.

Root movement of anterior teeth unavoidably occurs if brackets with

mesiodistally long arch wire-seating channels, such as tie brackets, are used.


11/19

This wet, IIIO~CIM~~~~ausrs stmrg n%tatlcc 10 tlic io1~~4 l)eing uscvl to til)

mitcl*iov t .eeth back into the extraction spaccs.

This I)revents simplex tlista 1

tipping of canines. Thus, the posterior anc~hor teeth will he moved too fa I

mesially and the ant,erior teeth will bc left out too far labially in the outer

cortical layer of the bone.

If tic brackets are introduced into this technique, many of the ad\-antage :

of the differential forcbc principle will be lost and it will then also be 101111~1

necessai >* to introduce cxstraoral anchoragi~. It is well known that it is iu-

possible to obtain a high standard of results with rectangular

illTall

wire tec*ll-

niqnes for the most pronounced forms of biniaxillary protrusion and the most

cstensi\c excess of tooth substance,

even if extraoral anchorage is also

eniploycd. IIiph standards for these paGents arc equally impossible wit,h tll(l

light wire tcchniyue it wide brackets, such as tic btxckcts, are crnployed, ww

ii extraoral

;IrlchOlYlgc~

is

nsd

ils

iI11 (Xtlil ilitl.

Howcve~n, if mcsiodistally llarro\\- 1)rackct.s that permit, unrc~strai~~~~tlmcsial.

tlistal, lillgllill, labial, and buccal tippin,

0 01 tll( (IiJ\VllS Of the t?PtIl ilIi ~lll~~lO)~~Yl

with the light witQ(l trc~hniqnc, so-callet difficult malocclusions can bc trcxtetl sue-

cessfl111~-. It is lhcn Ilot, necessary, ilrld of 110 ad\-antagc, to oml)lO~

PXt~KlOl'il1

a?lc~Jloragc.

I~p~i~-lhtiw~ Sw07~tl I).P~~~(jl~~I..s.--I)~llili~

the first two stages of lreatlnefit,

the crowns of the second premolar3 arc allowed to t,ip mesially.

While t he

second prcn~olars arc bein g uprighted during the third stage of trc~atment, t hc

force cserted t,o torqtlc their crowns (listally helps to prevent the molars from

being inovctl niesiall-.

It is ot vital iml)ort;utcr that the three stages of trcatmc,nt be kcl)i

rclparate. That, is, thcl operations that shoultl 1~ complctcd during one stage

should never 1~2 allowed to merge iill or overlap those of another stage oi

treatment.

I )iuing thcl first and sc~iitl stages of treatment the crowns 011all

teeth csccpt ttic anc.hor molars

illC

allowcil simply to til) in any dir&ions that

the)- t,cntl to take.

SimpIc tooth tipping is the simplest of all tooth movements

and rcqiGi*es less force than other nioveitients. Simple tooth tipping throws

less strain on the ancahor molars than tlo bodily tooth movements. Molar

anchorage is i.arefully guarded anil preserved 1)) biling required only to resist

tipping

inovc~iiicnts ol other lcct Ii.

JIolar anchorage faitnro is prevented in

this wap.

.lrch Wiyes With Certic*l Spzcr,s.---auxiliary arch wires with verticaal

spurs are 1~4 to torque incisor roots lingually during the third stage of treat-

ment, instead of the vertical spurs placed in the main arch mire that were for-

merly used (Figs. 5 and 6).

The change was made because it was found that, when a single arch wire

with vertical spurs was used the torque force exerted by the vertical spurs

t,ransmitted a spiral force along the buccal segments of thn arch wire. This

spiral force was transmitted distally along the a.rch wire through the til)-

back bends and therefore rotatcd the molars mcsiolingually.

Readjustments to dpyAzncrs.-In the case that has been described in this

article the upper and lower arch wires were removed once during the s~ond


12/19

st>aw of tleat111e11t.

This was don0 to shorten t.lic distal ends that protruded

too far back t,hrough t,he molar tubes.

In the third stage of treatment, the upper and lower arch wires were rc-

moved for adjustment, so that more accurate occlusion of the teeth could be

oht,ained.

These were the only t,wo readjustments made to the arch wires during

trea.trnent.

Sw~mnry

of

the Patients lrentment.--Dnring the first stage, the follow

ing operations were carried out simultaneously :

(1) Irregular teeth were

aligned. (2) The deep anterior overhitc was eliminated. (3) Class II occlusal

relations were corrected. (1) Upper and lower anterior teet,h were tipped back.

(5) The contours of both dental arches were brought to good proportions.

(6) Extraction spaces were made slightly smaller. (7) Premolar rotations

\v(re o\-ercorrc~ct,cd. Incidt~ntally, if patients have molar cross-bite, this is (OF

rccted during the first stage.

In the sc?contl stage all extraction spaces were completely closed. This

caused the upper and lower anterior teeth to be tipped back much farther than

at, t.he end of the first stage of treatment.

In

the third rrrd final stage of treatment the axial relations of all but the

molar anchor teeth were corrected. Of course, the molars were kept upright

t hroughol~t treatment.

lTtrktiows to the technique we sometimes required. For exarnplc, it is

sometimes found unnecessary to use arch wires with vertical spurs to upright

upper and lower incisors. This is because the labiolingual axial inclinations

of the upper and lower incisors are so good at the end of the second stage of

treatment that it. is then predictable t,hat vertical spurs will not be required.

IToweycr it, is still necessary in these cases to parallel the canine and premolar

roots.

In many patients whose upper and lower incisors arc only slightly

inclined lingually at the end of the second stage of treatment, these incisors

are made to incline labially, entirely as a result of the a&ion of the sprillg

mires used to torque the roots of the canines distally.

TREATMENT OF MILD DISCREPANCY CASES

In paGents whose discrepancies arc mild but sufficient to require extraction

of four first premolars, the six upper and lower anterior teeth have to be moved

back only a small distance.

Therefore, considerable mesial movement of t,hc

posterior teeth is required.

This is done by applying auxiliary arch wires with

slightly activated vertical spnrs leaning against the incisors at the time the

extraction spaces arc being closed. These vert,ical spurs prevent the anterior

teeth from being tipped back and ensure that the posterior teeth will move

mesially. This is the only exception to the rule that all teeth except, the anchor

molars must be allowed to tip until the third stage of treatment.

RESTJLTX OF TREATMENT OF OTHER PATI ENTS

lMateral Aw@al Resection of the Mandible (Fig. 22).-Immediately

after completion of active orthodontic treatment, which took eleven months,


13/19

Teeth E.ctmctco Uc~orc 01~thotlo~ tic Itwrdmmt Was Sought (rii~. 16).-

This patient had four first premolars c>stractcd several years before orthodontic

t,reatment was begun.

Fig. 27 shows a phot,ograph taken after completion ot

orthodontic treatment. Appliance therapy took four months. Figs. 28 and

29 show the patient before and after treatment.

Only

Pour Pirst Premolws Extructed in a Severe Malocclusion.-The pa-

tient whose condition is portrayed in Figs. 30 and 31 had four first premolars


14/19

extracted. Figs. 32 and 33 show the result of treatment. This patients con-

dition is presented because it shows that maintenance of stability of mm-

dibular anchorage for Class II elastics is not a difficult problem when diffcr-

cntial forces are used fey all aspects of treatment. Appliance therapy took

Fig. 24.

Vig. 21;. Kc. 27

six nut1 one half mouths.

Photographs taken before trcatnumt (Figs. :1-l and

35) and after treatincnt. (Figs. 36 and 37) indicate the improvement in facial

appearance. The final l~hotopral~hs were taken three years after completion of

the retention period.


15/19

ix:. :.

Fig. :i 1

ix. 3

Fig.

3 :i

Fig. 34. vip. 3.i


16/19

Fig. 36.

Fig. 37.

Fig. 38

Fix. 39.


17/19

Tr1~1601t~~)~t u/ futif ,I/ ICillr. /~rrp~:lc tl /,.pp I (trrrinc.~~--llle ~)a I iellt. wln+x~

c~oiltlit.ion

l)eIorc alltl ilttcr

treat fnent, is

Iwlt 1~ay~Yl

in Fig.

:3X had llillil.1;1 I inl-

I)ac%ioll ol an uplwr atluli. canine.

.\l)l)liaiic~c thcral)~~ toolr icn nronl IIS.

The I~nie covering this canine was removed and a pin was inserted in lhc~

tooth, as indicated in Fig. 39.

Although the apes of the root of the lateral

incisor was resorbed, this tooth has reniaincd vital.

Fig. 40 shows the crown of this canine surgically uncovered.

It shows also

the method used to move it

into

alignment,. In I3,.

0. 11 the canine is seen to 1x1

in alignment.

Figs. 42 to 45 show the l)atients face l~ciorc and after trcatnrent. The

final photographs were taken two years after treatjment.

It is routine practice to use the light. arch wire t.echnique to elevate

severely impacted teeth, whether they 1~ incisors, canines, or premolars. Third

molars are also elevated by this method if there is sufficient space for them.

This elevation of impacted teeth is always done simultaneously with t,he rest,


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of treatment that is required.

Since it is done during the first stage of treat,-

ment, the total time of treatment is not indefinitely prolonged as it is when one

merely uncovers impacted teeth and waits for them to erupt of their own

accord. The light arch wire force is most suitable for moving impacted teeth

rapidly without moving the anchor teeth involvrtl.

CONCI,CSION

In conclusion it is necessary to point out that it is not hecause of supcrioi

skill with their hands that orthodontists obtain superior results with the light

n-ire technique as compared with the results that they formerly obtained with

other techniques. The reason for this is that optimal arch wire and ruhbcl

Ligature forces arc delivered throughout treatment with the light wire technique.

Furthermore, when other techniques arc empIo,vc~d for treatment of those frc-

quently occurring scvcrc Class II conditions that arc compIicat,ed by marked

cscess of tooth size over jaw size, no more is plnnncd for and no morc is achieved

than to lcavc the lower bucc;ll teeth ill sIi&tl,v distal occlusion ;Ind also t)o Icave

the crowns of the upper incisors with iI lingual inclination and the crowns of

tlic Iowcr incisions wit,Ii ;I Iahial in~liniltiori in ortlcr lo Icssen the otllorwisc con-

sidcrnl)Ie ovcrjct ol the uppcr incisors.

III caontrast, with tht> light, wire tcch-

niquc, thcsc SWWP Class TT conditions (YIN IW lxmght, to that high standard


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Documents

Light Archwire Technique