Download For Total Quality Orthodontic Care

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Clinical Tips
For Total Quality Orthodontic Care
Authors:
Dr R.B. Sable, MOS, M. Orth RCSEd
Professor and HOD
Depa rtment of Orthodontics and Dentofacial Orthoped ics
Bharati Vidyapeeth University.
Denta l College and Hospit al. Pune
E-M ail : rbsa bl e@gmail .com
Prof Gdur;
5
~I ;c har ~
Prof. Gauri S. Vichare, MOS, M. Orth RSCEd
Professor.
Depa rtment of O rthodontics and De ntofacial O rth oped ics
Bharati Vidyapeeth Universi ty.
Dental College and Hospital . Pun e
E-Ma il: drga uriv@gmai l.com
Abstract
In order to provide consistently high quality care, we need to follow certain guidelines which we
think are very important for leday's orthodontic graduates to implement in the day-to-day routine
practice. These tips will offer a route map for aspiring young orthodonist seeking to do the best
for their patients. These may also be of interest to experienced colleagues w anting to overcome
shortcomings' in some of their results and refi ne their treatment mechanics. Objective of any
orthodontic treatment is to achieve the best results with relatively simple & and comfortable
appliance technique. Goal directed orthodontic treatment is extremely important. If the goals
are not kept in mind from the diagnosis and treatment planning phase through the phase of
retention, continuous errors can be made. In this article the authors w ill provide few clinical Ups
to enhance the quality of orthodontic treatment with PAE appliance.
keywords
Fixed bite plate, Rainbow effect. Round tripping. Basewire, Double loop archwire, load-def1ection
rate.
Selection of prescription
Introduction:
I)
Medical & dental trea tme nt is based equ ally on
science. tradi tion & clinical experience. When the
origi nal SWA became available in 1972 it was based
on science. but incl ud ed many oi the tradi tional
features of Siamese edgewise brackets. Now we have
the third generation oi prej udiced edgew ise brackets
(PAE) so we can input our cli nica l experience. While
providi ng high quality resul ts the treatment time should
no t be longer . One needs to remem ber the
biomechanics and it' s appli ca tion whil e doing the
adj ustments in each stage. All th e steps should be done
ca refully and sufficient time should be allowed for the
applia nce to express bui lt -i n fea tures.
Today 's orthodont ist has a choice of hundreds of
prescriptions avai lable. Genera ll y an orthodon ist is
influenced by the prescription in which he/she has been
trained at the graduate level. Although the resu lts do
not solely depend on the prescription that is used for a
pa rt ic ul ar maloccl usion. however to achieve high
qual ity results certain points should be remembered
while selecting th e prescri ption for a particula r type of
maloccl usion is that built-in featu res should be known
and th eir applicati on should be understood.
The contemporary applia nces have some variations in
the prescr iption. An important poi nt is that unless the
app liances have been identified properly, one cannot
47
,
be successful in getting high quality result s in a
particular case.
Criterions for selection a particular
prescription:
a I In cases w ith severe crowding and rotated lower
in cisors it is very difficult to place a twin bracket.
It woul d be a wise decision to select a si ngle bracket
as the torque values for lower incisors are simi lar
in both types of brackets. This offers more interbracket spa n, redu ces the force level.
b) There are 3 different torqu e va lues for ca nine
brackets which ca n be selectively utili zed
depe nding on the ca nine position in th e
ma locclusio n. For exa mple positi ve torqu ed
(+3 or +7) in narrow arches and buccally blocked
out ca nines with prominent roots. Similarly negative
torque ca nine brackets are effecti ve in palatally or
linguall y impacted canines. This offers good root
control during the treatment. Zero can ine torque
brackets should be elected for cases where th e
ca nine root is positioned properly in the cancellous
bone.
Fig. 1 : Modified ·W" arch for molar
appliance. But patient compliance with thi s removable
plate is very poor because it is very cumbersome when
worn with brackets and also ca uses oral hygiene
problems. In our practice since last many years we
have been using fixed acryle bite plate described by
Ballester2 (Fig. 2). Anteriorly it has thi ck acrylic flat
bit platform which is joined posteriorly with .032" HRSS
wire soldered on palatal surface of maxillary first molar
bands. The thickness of the acrylic is adjusted in such
way that the interocclusal clearance should be 3 to 4
mm (within free way space). This is very effi cient
particularly in Class II Division 2 cases which makes
it possible to place brackets simultaneously in both
arches. This disoccludes the mandibular arch in all
three directions . In selective cases we use vertica l
elastics on posterior teeth for extrusion and correct ion
of curve of Spee as shown in Fig. 3. It is also useful
along with utility arch to stabili ze the upper molars . In
growi ng chi ldren it causes increase in the lower anterior
face height by enchanci ng the erupti on of posterior
teeth .
c) Most of the time mandibular second molars are
lingually inclined . These molars need bucca l crown
torque. Whil e selecting a tube for lower second
molar one should select lower torque va lues which
w ill make the correction faster.
d) In second premolar extraction case or single arch
extra ction case there is tendency for mesio-palatal
rota ti on of maxi llary molar during space closure.
This rotation can be prevented by selecting the
upper molar tubes with distal offset (10' offset)' .
II) Banding & Bonding
It is very important before placing the first aligning
arch were that the anchor molars are in proper position .
For eg. in Class II maloccl usion a many times maxillary
mol es are mesiopalatall y rotated. If this rotation is
severe, then it should be corrected before placing the
appliance. Thi s can be effecti vely corrected by using
modifi ed qu ad helix or 'W ' arch (Fig. 1). This helps in
gai ning space as well as easy archwire insertion and
gives good control over anchor teeth .
Use of fixed bite plate
In deep bite cases and reduced lower facial heigh t
wi th strong musculature, somet imes, it becomes very
difficult to bond the mandibular arch to correct the
curve of Spee. In such conditions, generall y removable
ant erior bite pl ate ca n be used along with fi xed
Fig. 2 : Fixed bite plate
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reverse of this should be done. Mild o cclusal cant can
be corrected by changing bracket positions, such as
placing the brackets more cervicaly on the side where
occlusal cant is upward and more occlusally where
cant is downward.
Segmented technique approach can be considered in
extraction cases where the canines are severely
displaced.
III) Aligning Arch wires
Appropriate arch wires with proper arch from should
be selected. The aligning arch wire should be
preferably 'A' Niti (super elastic). These wires have
low load deflection rate which provides relatively
constant moment-to-force ratio with concomitant,
forecastable dental movement. Increasing patient
comfort and reducing the number of visits while
lowering potential tissue damage are additional
Fig. 3 : Fixed bite plate with Vertical elastics
Bonding
Precise positioning of the brackets is the single most
important step in achieving more accuracy in finishing.
The preferred option for bonding is indirect bonding
procedure. Before starting the bonding whatever
esthetic reshaping is required to modify the morphology
should be done, which enables to get perfect bracket
positioning. Modifi cation of the tooth morphology
should be done for fractured incisal edges, conical teeth,
peg shaped teeth and teeth wh ich have a very bulky
labial surface.
features of low load deflecting rate wires. Initial arch
wire should not be kept for longer time (preferably not
more that 8 to 12 weeks). These wires will cause
movements of reactive anchor teeth as well as active
teeth which will result in anchorage loss. Similarly
they will also tend to extrude the incisors and deepen
the bite & sometimes widen the arch form .
Many times the operator gets tempted to engage the
flexible arch wires in all the teeth on the first day itself.
If there is no sufficient space available then the arch
wire engagement should be delayed till the space is
opened.
In second premolar extraction cases it is always better
to tip the first molar tube on mesial side (0.5 mm more
cervically) similarly the bracket of first premolar should
be tipped more distally (Fig. 4). This is to enhance the
root up righting of molars as well as premolars.
Canines which are placed too far away from the line
of occlusion need special consideration for the
alignment. If low modulus wire is used indiscriminately
by engaging all the teeth in the same visit, anchor
teeth will move as well as the active teeth. An example
of this is seen in Fig. 5 where severely displaced or
rotated teeth are engaged in the arch wire, after some
time the adjacent teeth show unwanted movements in
all three directions along with canting the occlusal
place. This "wiggle" of reactive teeth is undesirable,
because of attendant, uncontrolled periodontal stress,
and an increased potential of tissue resorption related
to "round-tripping" the reactive teeth 3
Fig. 4 : Modified placement of lower first premolar
bracket and molar tube.
We prefer to give .01 6 SS Austral ian wi re with off-set
as a base wire along with Niti wires. Fig. 6
demonstrates the advantages of engaging a relatively
large number of teeth on a stiffer wire to improve
anchorage, while using low modulus wire to engage
the teeth targeted for movement.
In some cases bracket positions should be altered as
the situation demands. In deep bite cases when incisors
are extruded, the brackets should be placed 0.5 mm
more incisally and on premolars should be 0 .5 mm
more cervically. This will help in correcting curve of
Spee as well as deep bite. In open bite cases exactly
Deepening of bite will occur in the aligning stage when
incisors are engaged in continuous arch wire in a case
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Fig. 5 : Undesirable effects of the flexible wire.
Fig. 6 : Suggested arch wire combination to avoid undesirable effects.
wi th distall y tipped canines (Fig. 7). Thi s ca n be
prevented very well by bypassing the incisors till the
ca nine gets uprighted to avoid the extrusion of incisors.
twice activated wire approaches the mo ment from a
single activation 4 .
Importance of laceback and steel ligation should not
be ignored. At the end of alignment stage -make sure
that all the rotations & axial inclinations are fully
corrected before proceeding for retraction & space
closure.
V) Intermediate wires
Before proceeding for can ine and incisor retraction,
we recommend use of 16X22 N iti w ire in 018 slot.
These wi res should be engaged fully into all brackets
and should be kept for 4 to 6 weeks . These arch wires
help in completing the alignment & leveling before
the next tooth move m ent is initiated . Thes e
intermediate arch w ires are also importa nt after the
completion of canine retraction and incisor retraction
as prefinishing wires.
IV) Follow-up visits
In the follow up visits, the case should be eva luated
for any need for rebonding of brackets. The lacebacks
should be tightened every visit. Elastic modules should
be replaced by steel ligatures. The fl ex ible wires should
be progressively engaged in the slots by unty ing and
retying. When the wire is untied and retied a higher
moment is produced - al most twice the moment as it
is produced w hen the wire is left in place. As the wire
continues to deactivate, the moment produced by the
Before starting the canine retractio n one has to make
sure that canines are upright. Many times in extraction
cases the canine tips back even with simple laceback
force. On the aligning arch wires such canines should
be uprighted by putting intermediate w ire before
starting the retraction of ca nines . Th is is one of the
Fig. 7 : Bypassing the incisors in distally canines will prevent the extrusion and deep bite.
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most important reason for losing the vertica l control or
deepening the bite.
VI) Canine retraction
It is essential to keep the 016 5.5. wires in 018 slot
w ith bite opening curve for a period of 4 - 6 weeks
before starti ng the ca nine retraction to avoid binding.
Too fast retraction of ca nines by frequent activation
should be avo ided. The canine by frequent activation
should be avoided. The ca nine should be allowed to
' Walk' in the space by alternate crown and root
movement. In our experience the power chai n shou ld
not be changed in less than 6 weeks w hen cani nes are
being retracted with elastic force. When Niti coi l
springs are used the force shou ld be checked
periodica ll y.
In our experi ence it is better to consider the midline
correction at this stage by controlling canine retraction.
VII) Space Closure
One can use any mechanies for retraction as slid ing or
loop mechanics but the important rul e is that watch
the incisor torque whi le retracti ng the anteriors. As the
incisors are retracting the torque is reducing and the
bite starts deepening. In such situation one should stop
the retraction and control the bite and torque first and
then again continue the retraction. In loop mechanics
before activation watch that the legs of the loop have
comp letely closed . When the loop is not fully closed
then do not activate the loop at that vis it fully closed
then do not activate the loop at that vis it (fa i I safe
mechanism)s If this is noticed for consecutive 2 visits,
it is an indication to change the wire as the springin ess
of loop has reduced. It is advisable to change the
closing loop arch wire after about 3 to 4 mm of space
closure.
Fig. 8 : Rainbow effect.
a) Closure of large spaces.
Elastic chai n is not recommended for clos ure of
multiple interdental spaces. When spaces are present
in many teeth elastic chain should not be stretched
over many teeth as they produ ce large forces. This
also causes rotations and flattening effect of on the
teeth. El astic chains are useful for closure of minor
spaces between 2 to 3 teeth or also prevention of spaces
from openi ng.
When closing loop arch wire is activated by addition
of alpha & beta moments, it is mandatory to remove
the 'rainbow effect' in the anterior segment and torque
in the poserior segment of the arch wire before insertion
(F ig. 8). If this is not done, the effect is seen as central
incisors are more intruded than the lateral incisors in
the anterior segment and hanging of palatal cusps in
the posterior segment.
b) Double loop arch wire for space closure:
We have been usi ng very useful adjunctive in space
closure by loop mechanics. When the maxillary
canines are retraced to Class I position there are space
mesial and distal side of the ca nine. At this stage this
double looped arc h wire is very efficient in space
closi ng. We give the same teardrop 100p6 mesial to
can ine and another distal to canine on both the sides
(Fig. 9). A 15-20° alpha bend on the mesial loop and
15-20° beta bend is given on the disal loop. In our
experience this double loop space closing arch wire is
very effective.
The closing loop arch wire shou ld not be activated in
the first visit. Activation should be started in the
following visit by opening the loop 1 mm at a time.
Class II elasti cs ca n be carefull y used for sagittal
correction along with closing loop arch wires. Thi s ca n
cause of torque deepening of bite.
51
6 weeks before debond ing. The verti ca l settling elasti cs
should not be used longer than 3-4 weeks.
If all the steps are done carefully, it is possibl e to get
high quality results.
REFERENCES
1. Mclaughlin RP, Bennett]C, Tri visi H . Systemized
Orthodontic Treatment Mechanics. London : Mosby
international Ltd. 1st edition, 2001.
2. Ballester A. and Langlade M .: Unlocking the
Malocclu sion wit h a Semifixed Bit e Plate ,
j .Clin.orthod.35:544-548,2001 .
3. Stan ley Braum, Robert C Sjursen, Harry L. Legan,
Variabel mod ulus orth odonti cs advanced through
an auxili ary archw ire attachment. Angle orthod
1997:67(3):219-222
VIII) Finishing & Detailing
While achieving all the objectives if all the steps are
followed properly then finishing becomes easy and is
of short duration. There should be check-list of all the
objecti ves of the finishing stage shou ld be strictly
followed. All the micro-esthetics and macro-esthetic
criteria should be followed. The finishing wires should
be fu ll size and should be tightly cinched & kept
minimum for 3 month.
4. Burstone CJ, Qin B, Morton jV. Chinese NiTi wirea new orth odontic all oy. Am j Orthod . 1985
jun;87(6):445-52.
5. Profit WR: Co ntemporary Orthodonti cs- Fourth
Edition.2007.400
6. Alexander, R.G.: The Alexander Disciplin e:
Contemporary Concepts and Philosophy, Ormco
Corporati on, Glendora, CA, 1986.
The elastics should not be continued till the day of
debonding. The elastics should be discontinued at least
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