Refined begg /certified fixed orthodontic courses by Indian dental academy

REFINED BEGG
STAGE II & PRE STAGE III

INDIAN DENTAL ACADEMY
Leader in continuing dental education
www.indiandentalacademy.com

OBJECTIVES:
Similar to conventional Begg –
1. To maintain all the corrections achieved during stage I
2. To close all the extraction spaces. This done by further
retraction of the anterior teeth, by protraction of the
posterior teeth, or a combination of both. The nature of
initial malocclusion, or, the anchorage requirement
determines which of the above 3 modes of space
closure is indicated in a given case.

In addition, the stage II of the refined Begg aims at the
following:
1. Controlled tipping of the incisors, when space closure
is to be mainly achieved by the anterior retraction.
2. Preventing excess tipping of the anteriors (by using
efficient brakes), when space closure is mainly
achieved by protracting the posteriors.
3. If the molar relation is not fully corrected at the end
of stage I, this correction is also achieved during the
stage II.
4. In the 1st premolar extraction cases, crossbites and
rotations of the 2nd premolars are corrected during this
stage.

ARCHWIRES :
Premolar extraction cases – 0.018” P or P+, or, 0.020” P
wires, depending on the severity of initial malocclusion.
If the stage I corrections involved extreme deep bite,
badly distorted arch forms or severe rotations, new
archwires are made for the 2nd stage in 0.020” size.
Otherwise, 0.018” wires of the stage I can be
continued during the stage II also.
Heavy 0.020” archwires are extremely effective in:
1. Maintaining the rotational overcorrection, deep bite
correction and arch form.
2. Resist disto-buccal rotational tendency of the molars
due to class I elastics used during the space closure.

Since the bite opening requirement is fulfilled by the
end of stage I, the anchor bends are reduced to a level
that will maintain this correction. A reduction in the
anchor bends is necessary, because a continued use of
high degree of anchor bends will lead to excessive
tipping of the molars, specially the upper ones. The
degree of bend in 0.020” should be less than in 0.018”
wire for the same bite opening effect.
Other factors like the initial severity of the deep bite,
mild bite deepening effect of the MAA, and the need to
continue class II elastic for correcting the inter-arch
relation, should be considered for deciding the amount of
anchor bend.

The premolars are bypassed till the spaces close, except
when they are in disto-buccal rotation. Such rotations
require engagement of the archwire in the slot either for
rotational correction using modules, or for holding the
rotational correction using rotational springs. This is
done towards the end of stage II and anchor curves are
used instead of anchor bends.


CONTROLLED TIPPING OF THE INCISORS:
MAA for lingual root torque is a must during the stage II
for controlled lingual tipping of the incisors during their
retraction. In some cases, the lower incisors would have
received a MAA for labial root torque during stage I.
even such teeth would
need a MAA for lingual
root torque, when they
are to be significantly
retracted during stage II
in order to prevent their
uncontrolled tipping.

If the canines appear to tip distally excessively, 0.010”
uprighting springs on them minimizes their uncontrolled
tipping.
The adequacy of anterior retraction is judged clinically:
The retracted incisors should appear upright or slightly
retroclined, depending on whether they were moderately
proclined or severely proclined respectively to begin with.


BRAKING MECHANICS FOR PROTRACTING
THE POSTERIORS:
The amount of protraction of the posterior teeth
that is required for complete closure of the extraction
spaces varies under different situations. In cases of 1st
premolar extraction for correction of extreme anterior
crowding, severe proclination or excess deep bite –
only small amount of space may remain after these
corrections are achieved. Hence minimal protraction is
required in these cases.

2nd premolars would be extracted in some other cases
when these corrections are required to a lesser extent,
and the patient has a good profile. More of the
extraction space would remain at the end of stage I in
such cases, and this will have to be closed by
protracting the posteriors. There are also cases wherein
the 2nd premolar extraction in one of the arches is
undertaken mainly to mesialize the molars to correct
the molar relation to a class I.

When space is to be closed mainly by protraction
of the posteriors – it can be done by using efficient
braking mechanics.
The ‘brakes’ reverse the anchorage site from the
posterior to the anterior segment by permitting only
the bodily movement of the anterior teeth, instead of
allowing them the freedom of tipping.

This conversion of tipping to bodily movement is either in
a mesio-distal direction for the canines and lateral incisors,
or in a labio-lingual direction for the incisors. The former
is achieved by using braking springs or ‘T’ pins, while
latter is achieved by using some torquing component on
the incisor teeth.


The commonly used brakes are
as follows:
1. BRAKING SPRINGS –
These are passive uprighting
springs made in 0.018”
wire, which almost fill the
bracket channel.

2. ANGULATED ‘T’ PINS –
These pins maintain the tipping already brought
about, but prevent further tipping.


3. COMBINATION WIRES –
These are made either of stainless steel or alphatitanium alloy. The anterior segment is 0.022”× 0.018”
(ribbon mode) and the posterior segment is in 0.018”
round cross-section. The alpha-titanium wires being
softer are easier to engage in the anterior bracket slots.
However they are more prone to distort under occlusal
forces in the posterior area, especially in the lower arch.
When such distortion is anticipated, a stainless steel
combination wire is preferred.


Torque in the anterior
segment can be precisely
built to the required degree,
using a 0.022” torquing
turret in which the wire is
positioned in a ribbon mode.
It must be remembered that
greater the torque built in the
anterior segment, more bite
deepening effect it will have;
besides the shearing force on
the brackets, which tends to
open the slots or dislodge
the brackets.

Since combination wires are expensive, rectangular
stainless 0.022”× 0.018” sectionals, suitably torqued in the
same ribbon mode, can be used piggy back over a round
0.018” base wire, both held together using hook pins.
4. TORQUING AUXILLARIES:
A two spur or four spur
auxiliary, which is activated
to the desired extent, or a
MAA design in 0.010” or
0.011” size can be used as
a braking mechanism along
with a strong base wire
(0.020” or atleast 0.018”)

DEROTATION OF PREMOLARS:
A. Non-extraction treatment cases1a. First premolar having MB
rotation and 5 and 6 normal.

1b. The first premolar and molar
are normal but second premolar
has a MB rotation


2. The 4 and 5 both have MB rotations.

3. The 4 has DB rotation and the 5 has MB rotation.


4. The 4 has DB rotation and the
5 has MB rotation.

5. The 4 or 5 has DB rotation but the other premolar is
normal.
a. If mild – bracket placed off centered.
b. If severe – along with off centered bracket,
flexible sectional wire such as NiTi
c. If so severe that bracket cannot be placed off
centered because of extreme tooth displacement, it
is placed in center of the tooth and derotation
carried by rotation springs

B. 1st Premolar extraction cases –
1. MB rotation of 5 can be corrected as described as
for nonextraction treatment. A bracket is placed on
5 towards the end of stage II.
2. DB rotation of 5 can be corrected by placing a
bracket towards the end of stage II and then
derotating with the help of rotational module or a
spring.

C. 2nd Premolar or 1st Molar extraction cases –
Brackets are placed from the beginning in these cases
to avoid extrusion of the premolars as the anteriors
are retracted. However, they are bypassed by the
archwire and only ligated till the bite opens.
1. MB rotation of 4 is corrected
early from the palatal side
2. DB rotation can be corrected
as mentioned earlier in A5


ELASTICS:
Different configurations are employed during this
stage as per the patient’s needs –
1. Upper and lower class I elastics are required in most
cases.


2. When the molar relation is not fully corrected during
stage I, class II elastics along with lower class I
elastics are used at the beginning of stage II till the
molar relation is corrected. Thereafter, upper and
lower class I elastics are continued.


3. Class II elastics may be added to hold the corrected
molar relation, thus making a Z Configuration. However,
class II elastics should be used as sparingly as possible
because of their bite deepening effect. In many cases,
they are required only part time (for 8 hours during
sleep, or for 12 hours during night).


4. If the upper and lower teeth do not retract at the same
rate, only class II elastics are given when the overjet
increases (because the lower anteriors are retracting
faster than the upper)


On the other hand, only lower class I elastics are given
when the upper anteriors tend to go in a crossbite
relation (because the upper retraction is faster than
lower). When such abnormal relations are corrected,
the elastic pattern is reverted back for retracting both
the upper and lower anteriors together.


Strength of the elastics is also varied according to the
clinical requirement. Light (yellow) class I or class II
elastics are employed for anterior retraction. For posterior
protraction, stronger (green) class I elastics are employed.
Very heavy- blue or red elastics are seldom required, only
when green elastics are found ineffective as, for example,
in a low mandibular plane angle case.

PINS USED IN STAGE II:
Hook pins are used when the anterior retraction is
attempted in a controlled manner using MAA along
with a base wire. While these pins permit full freedom
of lingual tipping of incisors, they limit the distal
tipping of the canines. The rectangular sectional along
with the round base wire, or the rectangular component
of the combination wires for protracting the posteriors,
are also engaged using hook pins.


DURATION OF STAGE II:
The durations of stage I and stage II have an inverse
relationship in the extraction cases. Longer the stage I,
(i.e., more the utilization of extraction space for
relieving anterior crowding, retracting the anterior teeth
and intruding the anteriors) lesser will be the need to
close the space in stage II, hence shorter its duration and
vice versa.
The 2 stages together take approximately 1 yr to
complete in most cases, and should not take more than
1 yr 3 months even in very difficult cases.

CHECK LIST AT THE END OF STAGE II:
1. All spaces are closed completely
2. All teeth are well aligned
3. The anteriors are in edge to edge bite
4. The incisors are either are upright or slightly
retroclined
5. The canines and premolars are in mild to moderate
mesio-distal angulations
6. The canine and molar relations are class I

PRE STAGE III :
Most of the cases require the pre stage III
adjustments before going from stage II to stage III. This
is so because the premolars are usually not engaged in
the archwire till the extraction spaces are completely or
almost completely closed. Hence the premolars are at a
different vertical level than the molars at the end of stage
II.

Also, engagement of the archwire in premolar bracket and
the molar tube and the molar tube requires a horizontal
offset between the two, in order to compensate for the
greater buccal bulge due to bigger dimension of molars


Coordinated upper and lower prestage III wires

If the vertical and /or horizontal discrepancy is such
that the 0.018” wire of stage II cannot be engaged in the
premolar brackets at end of stage II, a slightly undersized
0.016” archwire can be used for one visit in order to get
the archwire engagement in the premolar brackets. The
horizontal offset between the canines and the premolar
brackets of the earlier stage I and stage II is eliminated
(unless required for holding the overcorrected position of
a canine that was initially buccally placed or
distobuccally rotated).

The offset is now made between the premolar and the
molar. A vertical adjustment is also made at the same
sight so as to engage the premolar brackets. These
adjustment should be semi passive so that they bring
about the required correction without creating excessive
forces. Then the heavier wires are employed for the
stage III.


The upper arch wire is given a gable bend distal to
the canine, while the anchor bend in the archwire is
eliminated. This helps in holding the deep bite correction
and simultaneous uprighting the molars, which had
tipped distally during earlier stages. The lower wire is
given both the a mild anchor bend as well as mild gable
bend. The position of anterior and posterior segments of
the wires are inverted to avoid excessive extrusive
effects on the canines on account of the gable bends.


The archwires ends are bent to prevent opening of the
extraction spaces. Light class II elastics are used, as
required, for maintaining the corrected relationships of the
anterior and posterior teeth. Occasionally, class I elastics
may be required for holding the closure of extraction
spaces.
The pre stage III adjustments are usually completed
within 1 month. If the discrepancy between the premolar
and molar positions is excessive, it may require two
months to go from the 0.016” archwire through the 0.018”
intermediate archwire to the 0.020 third stage archwire.

New impressions are taken at the beginning of pre stage III.
A lateral cephalogram and a panoramic radiograph are also
taken, which help in assessing the degree of root movement
needed during the stage III.


Refined begg /certified fixed orthodontic courses by Indian dental academy

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