VTO Planning for Orthodontic Treatment

VISUAL TREATMENT OBJECTIVE

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

The term visual (or visualized) treatment
objective (VTO) was coined to communicate the
planning of treatment for any orthodontic
problem.
Procedure based primarily on cephalometrics,
the purpose of which is to establish a balanced
profile and pleasing facial aesthetics and to
evaluate the orthodontic correction necessary to
achieve this goal.


V.T.O. is thus a dynamic cephalometric analysis
which takes into account both growth and
biomechanics, thus achieving its aim of being a
Visualized Treatment Objective.
It outlines a goal from the inception of treatment
and may be usefully employed in monitoring
growth and treatment progress.


It is like a blue print used in building the
house.
It enables development of alternative
treatment plans.
Term V.T.O. was coined by Holdaway.


V.T.O. accomplishes the following:
1. Predicts growth over an estimated treatment
time, based on the individual morphogenetic
pattern.
2. Analyzes the soft tissue facial profile.
3. Graphically plans the best soft tissue facial
profile for the particular patient.
4. Determines favourable incisor repositioning,
based on an "ideal" projected soft tissue facial
profile.

5. Assists in determining total arch length
discrepancy when taking into account
"cephalometric correction".
6. Aids in determining between extraction and
nonextraction treatment.
7. Aids in deciding which teeth to extract, if
extractions are indicated.
8. Assists in planning treatment mechanics.


Rickett’s VTO
Ricketts stated that all treatment planning
constituted some type of prediction.
He suggested estimating the amount of change
that should occur by predicting the possibilities
of tooth movement & facial change.
He called his method of prediction a ‘dynamic
synthesis’ in which craniofacial growth & tooth
movement were predicted.
Also allowed for a forecast of the integumental
profile.

Basic planes and points


SEQUENCE
Cranial base prediction
Mandibular growth prediction
Maxillary prediction
Occlusal plane prediction
Dentition
Soft tissue

Cranial base prediction
Trace the Basion-Nasion plane.
Grow Nasion & Basion 1mm (average
normal growth) for 2 years.


Mandibular growth prediction
Rotation & lengthening
Rotation – From the effects of mechanics used
& facial pattern
Direction of effective growth is determined
The mandibular plane is influenced accordingly
Lengtheningcondyle-1 mm/yr
body -2 mm/yr

Superimpose at
Ba.
Rotate ‘up’ at
Nasion to
Open the bite.
Rotate ‘down’close the
bite.


Condylar axis and corpus axis growth


Symphysis construction


Maxillary prediction
1/3 rd of total facial ht increase is due to
upper face Ht increase.
Pt A is influenced by tooth movement
treatment mechanics is given consideration
while relocating it


Superimpose point
1
On original menton
&
Facial plane.
Trace palate


Point A changes


Occlusal plane position
Superimpose mark
2
on original
menton,
Facial plane.
Parallel mandibular
planes
Rotating at menton


Lower incisor position
Placed in relation to symphysis of
mandible.
Ideal position – 22° at +1mm to A Po
plane, +1mm to occlusal plane.
Angle increases 2° with each mm of
forward compromise.


superimpose corpus
axis at PM.
Place incisor at ideal
position.


Mandibular molar
Superimpose the
lower molar on the
new occlusal plane.


Maxillary molar
Traced in good class
1 position to lower
molar.


Maxillary incisor
Place in good
overbite overjet
position. Interincisal
angle-130°.


Soft tissue -Nose
Superimpose at Nasion
along facial plane. Trace
bridge of nose.
Then superimpose at
ANS along palatal plane.
Moving prediction back
1mm/yr along palatal
plane, trace tip of nose
fading into bridge.


Soft tissue point A and Upper lip
Soft tissue point A
remains in same
relation to Point A as
in the original tracing
Superimpose new &
old bony point A and
make a mark at soft
tissue point A.


Divide distance between ‘original’ & ‘new’ incisors into
Thirds.

Keeping occlusal
planes parallel,
superimpose mark 1
on tip of original
incisor. Trace upper
lip connecting with
point A.


Soft tissue – Lower lip, point B, soft tissue
chin


Superimpose
interincisal points,
keeping occlusal
planes parallel. Trace
lower lip & soft tissue
point B


Completed VTO


Superimpositions
1st check point :
Basion-Nasion at CC
point –
to evaluate facial axis
change, chin growth,
upper molar position.


Area 2 – Basion
Nasion at Nasion.
To evaluate maxillary
change.


Area 3 – Corpus axis
at PM.

To evaluate lower
incisors and molars


Area 4 – Palate at
ANS.
To evaluate upper
molars and incisors.


Area 5 – Esthetic
plane at the
intersection with
occlusal plane.
To evaluate soft
tissue.


Holdaway’s VTO
Holdaway VTO emphasizes soft tissue profile balance.
Main difference with Ricketts – Holdaway predicted soft
tissue profile first, then the position of maxillary incisors.
He believed that the mandibular incisor could not be
rigidly fixed to any anatomical landmark such as A-Pog
line.
Instead , the mandibular incisors should be placed
relative to maxillary incisors where adequate lip support
had been established.


Growth of the cranio-facial skeleton is predicted
for the estimated treatment time, and the soft
tissue profile between the nose and the chin
arranged to create an “ideal” facial profile for the
individual patient
Maxillary and mandibular incisors are
repositioned to eliminate lip strain

Allowance is made for probable post treatment
“incisor rebound”.

Maxillary teeth are positioned first, and
then lower incisors are repositioned to be
in harmony with the upper incisors

Following the repositioning of the
mandibular incisors, the resultant arch
length discrepancy may be calculated to
determine whether or not teeth should be
extracted.

1 Basion-Nasion line
(Ba N).
2. Line Nasion to point
A.
3. The Frankfort
horizontal plane
4. The Occlusal plane.
5. Downs mandibular
plane.
6. The facial axis
7. Holdaway'S line
8. The facial plane


OBJECTIVE : To
draw frontonasal
area, line Ba-N and
line N-A


OBJECTIVE : To express
growth in the frontonasal
area over a two-year
period.
Super impose on line
BaN and move the VTO
until there is 1.5 mm
growth in the fronto nasal
area
Holding the VTO tracing
in the position copy the
Ricketts facial axis


growth in a vertical
direction in the mandible,
and to draw the anterior
portion of the mandible,
soft tissue chin and the
mandibular plane of
Downs


Superimpose the
VTO facial axis along
the original facial axis.
Move the VTO
tracing upwards so
that the VTO Ba-N
line is above the
original Ba-N line,
the distance between
these lines should be
three times the
amount of growth
expressed in the
frontonasal area

growth in a horizontal
direction in the mandible
and draw the posterior
border of the mandible.
Superimpose on
mandibular plane and
Move the VTO forward
until the original and VTO
foramen rotundae are
vertically aligned


OBJECTIVE : To locate
and draw the maxilla, and
lower half of the nose
Super impose the VTO
N-A line on the original
NA line and move the
VTO up until the vertical
growth is expressed
above the Ba-N line and
below the mandibular
plane is in the ratio of
40:60


With the V.T.0. tracing in this position copy the
maxilla to include posterior 2/3 of hard palate,
PNS to ANS to 2mm below the ANS.
With the V.T.0. in the same position, draw the
new nose up to the middle of the inferior surface
of the nose.
Estimated growth usually parallels the contour of
the old nose in this area. Average nose growth is
1mm per year

OBJECTIVE : To locate
and draw the occlusal
plane
With the VTO
superimposed on line
NA, move the VTO
tracing so that the
vertical growth between
the maxilla and the
mandible is expressed
as being 50% above the
maxilla and 50% below
the mandible

Generally occlusal plane is located 3mm
below the lip embrasure. This permits the
lower lip to envelop lower1/3rd of upper
incisor teeth.
If cant of occlusal plane in original tracing
is correct then this should be maintained.


OBJECTIVE : TO determine the soft tissue
lip contour using the Holdaway line
When there is a uniform distribution of the soft
tissues in the profile and the upper lip is of
average length, and where the cant of the H line
is not adversely affected by excessive facial
convexity or concavity, the depth of the soft
tissue subnasale measured to the H line is most
ideal at 5 mm.
A range of 3 to 7 mm allows one to maintain
type with short and/or thin lips and long and/or
thick lips.

Also use of the vertical line from Frankfort
plane to the vermilion border of the upper
lip, which is ideal at 3 mm with a range
from 1 to 4 mm – Superior sulcus depth.
To find the point along the lower border of
the nose outline at which the new H line
will intersect it, both perspectives are
used.

Superimpose on N-A & VTO maxillary and draw
a line up a straight-edge tangent to the chin and
angle it back to a point where there is a 3 to 3.5
mm measurement to the superior sulcus outline
of the original tracing and draw the H line to this.
As one redrapes the superior sulcus area to the
new tip of the upper lip point, a 5 mm superior
sulcus depth develops almost automatically


Use of the Jacobson-Sadowsky lip-contour
template is recommended.
Second, with the tracing still superimposed on
the maxilla and line N-A and using the occlusal
plane as a guide for the lip embrasure, draw the
upper lip from the vermilion border to the
embrasure.
Then from the point on the lower border of the
nose where its outline stopped on the VTO, draw
in the superior sulcus area. This is a gradual
draping to the new vermilion border outline.

Third, superimpose on line NA and the occlusal
plane.
Form the lower lip, remembering that from 1
mm behind the H line to 2 mm anterior can be
excellent, depending on variations of thickness
of the two lips.
Again, most cases will fall on the H line or within
0.5 mm of it.


Objective – To relocate Maxillary central
incisor
Lip Strain - in well-balanced soft tissue profiles
the distance along a horizontal line extending
between a point 3mm below the original point A
to the point where the line crosses the upper lip
is within 1mm of the distance between the labial
surface of the maxillary incisor to the tip of the
upper lip.
Should the lower measurement be less than
within 1mm of the upper measurement, then lip
strain is said to exist.

To eliminate lip strain where it exists the
upper incisor is moved back to allow the
aforementioned readings to be within
1mm of each other.
Where no lip strain exists retraction of the
maxillary incisors allows the upper lip to
move backwards an equal amount, i.e. lip
and incisors maintain a 1:1 ratio.

Maxillary Incisor Rebound— Generally,
during posttreatment maxillary incisors
tend to move labially 0.5mm in Class I
cases and 1.5mm in Class 11 cases. This
is referred to as "Incisor Rebound".


Superimpose the V.T.0. tracing on the N-A
line and the maxilla and trace in the
maxillary incisor, taking cognisance of the
amount it is to be repositioned.
The axial inclination of this tooth is judged
and the occlusal plane is used to locate it
vertically. The tip of the maxillary incisor
touches the occlusal plane.

OBJECTIVE : to reposition lower incisor and
calculate resultant arch length change
judge the position of
the lower incisor
To calculate lower arch
length change,
superimpose tracing on
mandibular plane and
register on symphysis.
Measure the distance
between old and new
incisor position and
double this
measurement to
determine total arch
length discrepancy

OBJECTIVE : To reposition lower first molar, use the
plaster casts to determine arch length discrepancy due to
crowding and/or rotation.


OBJECTIVE : To reposition maxillary first molar
Using the occlusal plane and lower first molar as a guide
draw the maxillary first molar in good Class I occlusion with
the lower first molar


OBJECTIVE : To complete art work
ANS to upper incisor
Anterior portion of hard palate
Lower alveolus lingually and labially


DENTAL V.T.O.
Proposed by Richard P. McLaughlin & John C.
Bennett. (JCO 1999).
Designed to provide organized and simplified
information to help in diagnosis, treatment
planning, and the extraction/nonextraction
decision.
It should be used as an adjunct to, but not a
substitute for, conventional cephalometric
analyses.

It takes little time to complete and
occupies only a small part of the treatment
card.
Progress can be checked by referring to
the dental VTO at the patient’s regular
adjustment appointments.


Consists of 3 charts :
Chart 1 records the
initial midline and first
molar positions with
the mandible in
centric relation.


Chart 2 measures the lower arch
discrepancy, similarly to the Steiner
analysis. The four primary factors in each
case are:
1. Space required for relief of crowding,
measured from canine to midline and from
first molar to midline on each side.
2. Space required for the desired
correction of protrusion or retrusion of the
mandibular incisors.

3. Space required for
leveling the curve of
Spee.


4 .Space required for midline correction.
Four secondary factors that can sometimes
provide additional space are listed, if applicable,
below the primary chart:
1. Additional space from interproximal enamel
reduction.
2. Additional space from uprighting or distal
movement of mandibular first molars.

3. Additional space from buccal
uprighting of mandibular canines and
posterior teeth.
4. Additional leeway or “E” space.


The primary & secondary factors are added
together at the bottom of the chart to
determine the total lower arch discrepancy
from canine to midline and from first molar
to midline on each side.


Chart 3 records the
anticipated treatment
change in terms of
dental movements of
the first molars,
canines, and midline.


Case Report
12 year old male
presented with a
Class II skeletal
pattern.
Molar relation were
4mm Class II on right
side, 3.5mm Class II
on left.
Lower dental midline
was deviated 1mm to
right.

The mandibular arch showed 3mm of
crowding on the right side, all mesial to the
right canine.
Therefore, the amount of crowding from first
molar to midline was the same as the
amount from canine to midline.


The curve of Spee was about 2mm at its deepest
point.
Steiner suggested that leveling a 2mm curve of
Spee would advance the incisors 1mm, thus
requiring 1mm of space per side for the leveling
process.
Because the lower midline was deviated
1mm to the right, the midline correction would
require 1mm of space on the left side and provide
1mm of space on the right.

The mandibular incisors were inclined forward
(97° to the mandibular plane) and were
6mm in front of the APo line.
Without extractions,the incisors would either
remain in this position or, more likely, be
advanced farther.
With extractions, the incisors could be retracted.
Therefore, the decision was made to extract the
four first premolars and retract the mandibular
incisors 2mm.

Extraction of four first
premolars – produces
7mm space.


As total discrepancy
in lower arch
5mm/side, mandibular
canines needed to be
retracted 5mm into
the extraction sites.


Mandibular molars could be moved only
2mm. This demonstrated a need for
moderate anchorage control in mandibular
arch.
A mandibular lingual arch could be
considered during 3mm of canine
extraction.


Mandibular midline
needed to be moved
1mm to right.


4 possible methods of Class II molar correction
in growing patient :
a. Mesial movement of the mandibular first
molars (in this case, 2mm per side).
b. Distal movement of the maxillary first molars.
This is difficult in the presence of developing
maxillary second and third molars, but it can
be achieved.


c. Limiting forward maxillary skeletal development,

or retracting the maxilla. Because such
changes are difficult to isolate, it is debatable
how much is skeletal (above the palatal plane)
and how much is dentoalveolar (below the
palatal plane).
Nasion normally grows forward
about 1mm a year relative to sella, while A point
may be maintained or retracted relative to its
original position.

d. Forward mandibular rotation. This can
occur in two ways:
1) Mandibular growth. The direction of
overall facial growth is critical to the “expression”
of mandibular growth.
With more vertical patterns, there is less forward
expression of mandibular growth and hence less
interarch dental change.


2) Limiting vertical maxillary development.
Although sizable claims have been made
for this method, it is difficult to significantly
influence the normal vertical development
of the facial complex.
Even a small limitation can greatly
enhance a Class II correction.


In the present case, the
molar relationship on the
right side was 4mm Class
II, and since 2mm could
be corrected by mesial
movement of the
mandibular molar, an
additional 2mm of
correction was required.
On the left side, an
additional 1.5mm of
correction was needed.


A palatal bar & a combination high-pull &
cervical pull headgear were used to
preserve maxillary anchorage.


Taking into account the
2mm distal movement
of the maxillary right molar
and the 1.5mm
distal movement of the
maxillary left molar, the
canines would have to be
moved 9mm on the
right and 8.5mm on the left
to close the 7mm
extraction spaces.


A functional appliance could also have
been considered before fixed appliance therapy.
A good response to the functional appliance
might have reduced the amount of maxillary
anchorage support needed later. Extractions
would still have been required after the functional
phase, assuming incisor retraction was still a
treatment objective.


TOMAC: An Orthognathic
treatment planning system.
Proposed by Tony G. McCollum in 2001.
It is a surgical-orthodontic treatment
planning & prediction system designed to
identify the best possible soft tissue profile
by testing the effects of various
orthodontic & surgical options.


In the TOMAC VTO, the soft tissue goals are
traced in first, and the hard tissues are then
adapted based on known soft to hard tissue
responses.
The TOMAC VTO is constructed in three stages:
test, presurgical-orthodontic, and surgical.
The essential underlying principle is that the
soft-tissue profile is changed first, setting a goal
toward which hard-tissue changes are adapted.


Test VTO
– This is where the various orthodontic and
surgical options are tested and the optimum
combination is visualized.
– In the anteroposterior plane, the facial contour
angle (FCA) is changed to the chosen ideal.


Facial Contour Angle
The facial contour angle (FCA) is
highly relevant to the analysis
because it measures the convexity or
concavity of the face .


This angle is
formed by
tangents to
glabella and
soft-tissue
pogonion,
intersecting
at subnasale.


Line from glabella to
subnasale – Upper
facial contour plane.
Line from subnasale
to pogonion – Lower
facial contour plane.


The acute angle between
these planes is the facial
contour angle, which
describes the degree of
anteroposterior
discrepancy of the total
face.
Normal value – according
to Burstone is -11º ± 3º.


Varies according to facial type, with
leptoproscopic (long face) individuals
tending to be more convex, around -16°,
euryproscopic (short face) patients
tending to have more acute angles : -7°.


– The upper and lower jaws, or both, are traced
in their new positions according to the softtissue reactions to surgical movements, and
the teeth are then decompensated
accordingly.
– The incisor movements are measured and
reconciled with arch-length discrepancies and
with the physiological positions of the teeth in
the alveolar bone.

– In the vertical plane, the key is the position of
the maxillary incisor in relation to the relaxed
upper lip.
– The maxillary incisors are moved vertically on
the tracing, if necessary, into their ideal
positions relative to the upper lip, and the
mandible is autorotated so that the correct
vertical relationship of the maxillary and
mandibular incisors is obtained.


– The new Facial Contour Angle is measured
and compared with the chosen ideal Facial
Contour Angle .
– Appropriate anteroposterior jaw movements
are then effected to obtain the ideal total
profile.


– The teeth are decompensated into positions
most favorable to the desired surgical
changes, keeping in mind arch-length
discrepancies and physiological positions in
the alveolar bone.
– The incisor movements required to
accomplish the skeletal changes are
measured for use in the presurgical VTO.

Presurgical-Orthodontic VTO
– This is constructed from the information in the
test VTO.
– Any necessary incisor decompensations,
molar adjustments, and soft-tissue changes
become the orthodontic objectives prior to the
surgical procedure.


Surgical VTO
– The surgical VTO is constructed over the
presurgical VTO, with the surgical cuts
diagramed on the tracings of the jaws. The
simulated surgical movements are governed
by the decompensated positions of the
incisors.

– The soft-tissue profile is then drawn according
to the expected soft-tissue/hard-tissue ratios
of movement


Test VTO _- Hard & Soft tissues that will not
change after surgery

Mandibular structures after advancement

Incisor decompensation
needed to achieve best
profile.

Presurgical-Orthodontic VTO
– Construct a new VTO
to reflect the
orthodontic
movements that will be
needed to allow
surgery to create the
ideal (or nearest to
ideal) profile.
– Bite opening or
closing is measured by
the change in
angulation of the line
from condylion to
gnathion.

It is important to draw in the softtissue changes that will occur as a
result of any orthodontic
decompensation


Surgical VTO

Lew et al (1998) took a sample of 34 growing
Class II patients to assess the reliability of
manual & computer generated VTOs when
compared with actual treatment results.
Skeletal, dental & soft tissue measurements
were performed on the VTO & the posttreatment
changes.
Both methods were accurate when predicting
skeletal changes that occurred during treatment.

For soft tissue prediction, only slight difference
was seen with the computer being slightly more
accurate.
Both methods were moderately successful in
forecasting dental alterations during treatment.
Overall the prediction tracings were accurate to
only a moderate degree, with marked individual
variation evident throughout the sample.

Inadequacies of VTO
1) Use of average growth increments in
growth prediction.
2) The use of existing morphological traits
to predict future growth events.
3) The fallibility of presenting VTO
analysis as an exact representation of the
treatment outcome.

Conclusion
VTO can be helpful as a diagnostic &
treatment planning aid and as a reference
throughout treatment.
It is also useful in making extraction non
extraction decision.


With soft tissue responses to hard tissue
movements better understood than in
past, these & other influential factors could
be incorporated into computerized
technology, using multiple regression
equations to provide extremely accurate
treatment planning information.


References
1) Ricketts R.M. : Planning treatment on the
basis of the facial pattern and an estimate of its
growth. Angle Orthod 1957;27;14-37.
2) Ricketts R.M. : Cephalometric synthesis : An
exercise instating objectives & planning
treatment with tracings of head roentgenogram.
AJO 1960;46;647-673.
3) Holdaway RA : A soft tissue cephalometric
analysis and its use in orthodontic treatment
planning. Part 1. AJO 1983;84;1-28.

4) Holdaway RA : A soft tissue cephalometric
analysis and its use in orthodontic treatment
planning. Part II. AJO , 1984;85;279-293.
5) Jacobson A, Sadowsky PL : A visualized
treatment objective. JCO 1980;14;554-571.
6) Tony G. McCollum : TOMAC : An
orthognathic treatment planning system. Part 1 –
Soft tissue analysis. JCO 2001;35(6) ; 356-364.


orthognathic treatment planning system. Part 2
VTO construction in the horizontal dimension.
JCO 2001, 35 (7); 434-443.
orthognathic treatment planning system. Part 3
VTO construction in the vertical dimension. JCO
2001, 35 (8); 479-490.
9)Richard P McLaughlin, John C. Bennett : The
Dental VTO : An analysis of orthodontic tooth
movement. JCO 1999,33(7) ; 394-403.

10) Lew B. Sample,Lionel Sadowsky, Edwin
Bradley : An evaluation of 2 VTO methods.
Angle Orthod 1998;68(5);401-408.
11) Roberts M Ricketts, Ruel W Bench, Carl F
Gugino, james J Hilgers, Robert J Schullof :
Bioprogressive Therapy. Rocky
Montain/Orthodontics. 1980. page- 35-54.


Thank you
Leader in continuing dental education


VTO Planning for Orthodontic Treatment

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