Visualized Treatment Objective.ppt

Visualized
Treatment
Objective

 History of visual treatment objective .
 What is the purpose and applicability of VTO ?
 Methods of prediction:
1.by templates,
2.by cephalogram
 General concepts of VTO
 Advantages and disadvantages of VTO
 Surgical VTO

History
In early days of Orthodontic treatment, the original
diagnostic records consisted only of a set of patient
record and the patient’s were classified as Angle’s class
1 or 2 or 3 dental malocclusion.
Treatment prescription during those times basically
aimed at establishing class 1 alignment of the dental
arch. Therefore Orthodontics became branded as a field
dedicated to correcting occlusal disharmony rather than
looking through the facial changes occurring during the
course or as a result of the treatment being constituted.

The alignment of the teeth was confined to the upper
arch only, as the orthodontist during those times
believed that only the upper arch was quite obvious
when the patient speaks or smiles.
The basic objective to align the teeth was that if the teeth
were malaligned, they are more prone to /for decay. As a
result growth and treatment forecast terminologies were
obsolete during the past.
The recognition of jaws interaction and the position of the
teeth lead to a refinement of the diagnostic procedure
and treatment, wherein beyond dental terminologies all
other factors were analyzed.

This recognition occurred after the arrival of cephalometry
in 1930’s.
Malocclusions were beginning to be classified based on
anatomical structure of the jaw. New vistas in orthodontics
like computer simulations of the treatment plan wherein
the patient is also allowed to make decisions with regards
to their own treatment are now on the rise.
For a successful treatment to occur, the term prediction
was considered as an important criteria.

Prediction
according to Kendall & Buckland – it is the
process of forecasting the magnitude of a
statistical variant at some point of time in the
future.
Baumrind suggested that the prediction of a case
assists the Orthodontist psychologically in
planning out the treatment process by removing
some part of the act & adding a little more
science.

Though prediction was considered as an important
criteria, the orthodontist faced problems with regards
to it due to,
a) variations in growth and development
b) variations in treatment.

The process of prediction can be
performed in 2 ways
manually computer (recent trends)

Manual prediction
Template prediction:-
Templates have been shown to be useful in
orthodontic diagnosis for comparing
cephalometric tracings to established norms.
a) In 1952 Baumrind devised a set of 4 templates to
be overlaid directly on a x-ray film by using
Down’s analysis.
b) Grainger & Popovich performed a study on a
population in Berlington & devised templates for
ages 3-6 yrs & 10-12 yrs that could be used to
assess antero-posterior, vertical & lateral facial
development.

c) Highley developed cephalometric standards for
children 4-8 yrs of age & also proposed sex
specific transparencies for each age level.
d) Johnston introduced a simplified method of long
term forecasting of growth wherein the tracing is
superimposed on a printed grid.

The most commonly used cephalometric templates are:
 The unisex Bolton templates for ages 1-18.
 The Burlington templates, in three basic
configurations, for ages 2-18.
 The original Burlington templates or the subsequent
Michigan modifications.
 Jacobson’s proportionate templates for orthognathic
surgery and orthodontic cases.
 Johnston’s template analysis.

Burlington prediction template

FORECAST GRID
L.E. Johnston has produced a diagram on the
assumption of regular annual changes and an
average direction of the growth.
He states that accurate prediction is made in 65%
of cases. He developed a simplified method of
generating a long term fore cast by use of a printed
forecast grid.
Each point was advanced on the grid unit per year using
a standard S-N orientation registered at S .
An example of template based on Rickets and
Burlington group study.

Advantages of Template analysis
 It provides an immediate picture of the
patient’s dentoskeletal structures without
any measurements or calculations.
 Outlines of hard & soft tissue
components can be judged easily.
 It allows comparison of the patient’s
tracing with an age-appropriate ideal
template.
 Templates are used based on average of
norms from several sources.

In both conventional cephalometric and
template analysis, there has long been a
need for an absolute reference point or
plane from which to measure
craniofacial deviations.
Many of the common landmarks are
sites of bone resorption or deposition
and therefore are constantly changing.
The relationships of landmarks to one
another are also affected by growth and
by the orientation of the patient.

Cephalometric Predicition
Cephalometric radiography was once employed primarily to
study the growth of the skull, following which it was later
recognized as a method for evaluating treated orthodontic
cases.
Mandibular movements & studies on dynamic occlusion
were other phases of its application included later.
Cephalometrics was not popular until they were utilized in
routine clinical practice as an aid in diagnosis & treatment
planning.

Origin of VTO
a) Ricketts in 1960 stated that all treatment planning constituted
some type of prediction of craniofacial growth & tooth movement
& termed this method of prediction as a Dynamic synthesis.
In Ricketts prospective, the VTO is like a blue print used in
constructing a house. It’s a visual plan to forecast the normal
growth of the patient & the anticipated influences of treatment so
as to establish the individual objectives to be achieved for that
patient.
Treatment for a growing patient according to Ricketts must be
planned & directed to the face & structure that can be anticipated
in future & not to the skeletal structure that the patient presents
initially.

b) Bench & Hilgers in JCO 1977 state that VTO
permits the development of alternative treatment
plans. They also state that after setting up the
teeth ideally within the anticipated/ grown facial
pattern, the orthodontist
1) Must decide how far he must go with mechanics
& orthopedics to achieve them.
2) Whether its possible to achieve them
3) What are the other alternatives.

• According to DR. ROTH the dentition can be
positioned objectively for esthetics only by
doing a VTO.
Dr.Reed A Holdaway in 1971 devised the
“Visualized treatment objective” a treatment
planning method based upon prediction & the
desired treatment objectives.
The Holdaway VTO emphasizes soft tissue profile
balance, whereas other analyses & treatment
planning methods reposition the dental structure
first thereby permitting the lips to drape over the
teeth.

In contrast to Ricketts, Holdaway believed that
mandibular incisors could not be rigidly fixed to any
anatomical landmarks such as point A to the
pogonion line. He proposed that mandibular
incisors should be placed relative to their maxillary
counterparts where adequate lip support has been
established.
Growth of the craniofacial 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. Having established the soft
tissue profile, the maxillary and mandibular incisor teeth are
repositioned to eliminate lip strain. Allowance is made for
probable post-treatment “incisor rebound”.

Guidelines are provided whereby the lips are graphically
repositioned. A template may be used to facilitate drawing the
soft tissue of the lips. This is followed by location of the maxillary
incisor teeth.
Finally, the lower incisors are repositioned to be in harmony with
the upper incisors. Following upon the repositioning of the
mandibular incisor, the resultant arch length discrepancy may be
calculated to determine whether or not teeth should be extracted
prior to orthodontic correction.
Should the computed information suggest that teeth be extracted,
the V.T.O. will yield information based on anchorage
requirements as to whether first or second bicuspids should be
removed, or whether the proposed treatment plan is feasible or
desirable

Jacobson & Sadowsky in 1980 JCO, state that VTO is a
procedure based primarily on cephalometrics, the purpose
of which is to establish a balanced profile & pleasing facial
esthetics & to evaluate the orthodontic correction
necessary to achieve this goal.
In attempts to make prediction – Hixon1972 pointed out
that the accepted standard error for most of the
measurements should not be more than 5 or 6% of the total
distance measured, because craniofacial growth is a
relatively slow process wherein a small error in
constructing the tracing can lead to a significant difference
in the results obtained.

Jacobson & Sadowsky JCO 1980 have listed the
advantages the VTO as follows,
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 favorable 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 non
extraction treatment.
7. Aids in deciding which teeth to extract, if extractions
are indicated.
8. Assists in planning treatment mechanics.
9. Assists in deciding which cases are more suited to
surgical and/or surgical- orthodontic correction.
10. It provides a visual goal or objective for which to strive
during treatment.

The advantages of the VTO are:
1. Establishment of specific treatment goals
2. Formulation of specific treatment plan to reach
treatment goals.
3. Assistance in making mid treatment correction
4. Assistance in determining if ideal treatment result is
attainable orthodontically / surgically.
5. Enhancing communication between patients and clinicians,
6. Allowing quantification of proposed movements to reduce
the difficulties in planning facial response to different
movements,
7. Allowing rapid comparisons of different treatment options
before arriving at a final treatment plan.

Despite the listed advantages of VTO limitations exist in their
implementation.
Inadequacies of VTO are
1. Use of average growth increments in growth prediction.
2. Use of existing morphological traits to predict future
growth events.
3. Failure of presenting VTO analyses as an exact
representation of treatment outcome

Ricketts prediction
1. The cranial base prediction
2. The mandibular growth prediction
3. The maxillary growth prediction
4. The occlusal plane position
5. The location of the dentition
6. The soft tissue of the face

After completion of the different prediction’s,
the VTO is taken and superimposed in the five
superimposition areas to establish individual
objectives for the case.
The use of superimposition areas and evaluation
areas to establish treatment design including changes
due to normal growth and changes due to various
treatment mechanics are different for each
individual because of his individual morphology and
facial type.

In order to forecast effectively and decide upon
the correct treatment design, it is necessary for
us to first understand the individual patient and
describe his basic facial, skeletal and
dental structures and secondly we should be able
to anticipate normal growth in amount and
direction in the various areas of the face and the
jaws and thirdly we should understand the
response of his individual skeletal and facial
structures to various treatment mechanics.

The five superimposition areas used
to evaluate the face are in the
following order:
1.The chin.
2.The maxilla.
3.The teeth in the mandible.
4.The teeth in the maxilla.
5.The facial profile.

Superimposition Area 1 (Evaluation Area 1)
The first superimposition (Basion-Nasion at
CC Point) establishes Evaluation Area 1,
within which we evaluate the amount of
growth of the chin in millimeters; any
change in chin in an opening or closing
direction that may result from our
mechanics; and any change in upper molar.
In normal growth, the chin grows down the
facial axis and the six year molars also grow
down the facial axis.

The second superimposition area
(Basion-Nasion at Nasion) establishes
Evaluation Area 2 to show any change in
the maxilla (Point A). The Basion-Nasion-
Point A Angle does not change in normal
growth. Therefore, any change in this angle
would be due to the effect of the
mechanics. With Evaluation Area 2, we can
determine whether we wish to use an
orthodontic or an orthopedic force on the
maxilla with a headgear.

Superimposition Area 3 (Evaluation Areas 3 and 4)
The third superimposition area (Corpus Axis at PM)
establishes Evaluation Area 3 and Evaluation Area 4,
which together evaluate any changes that take place
in the mandibular denture. In normal growth, the
lower denture remains constant with the APO Plane
(the denture plane).
In Evaluation Area 3, we evaluate whether we have
to intrude, extrude, advance or retract the lower
incisors, which helps us determine what type
of utility arch we will use.

In Evaluation Area 4, we evaluate the lower
molars to determine what type of
anchorage we need and whether we wish
to advance, upright or hold the lower
molars.

Superimposition Area 4 (Evaluation Areas 5 and 6)
The fourth superimposition area (Palate at ANS)
establishes Evaluation Area 5 and Evaluation Area 6,
which together evaluate any changes that take place
in the maxillary denture. In normal growth, upper
molars and upper incisors grow on their polar axis.
In Evaluation Area 5, we evaluate what we are going
to do with the upper molars— hold, intrude, extrude,
distallize or bring them forward.
In Evaluation Area 6, we evaluate what we are going
to do with the upper incisors— intrude, extrude,
retract, advance, torque or tip them.

The fifth superimposition area (Esthetic Plane
at the crossing of the Occlusal Plane)
establishes Evaluation Area 7 with which we
evaluate the soft tissue profile.
In normal growth, the face becomes less
protrusive with reference to the esthetic plane.
We use Superimposition Area 5 and Evaluation
Area 7 to evaluate the effect of our mechanics
on the soft tissue of the face.

VTO BY HOLDAWAY
The main difference between Holdaway’s VTO and
other types was that, Holdaway predicted the soft
tissue profile first, then the positions of the
maxillary incisors. Holdaway re-emphasized the
importance of soft tissue analysis as he quantified
certain soft tissue relationships in harmonious
faces. In contrast to Ricketts, Holdaway believed
that the mandibular incisor could not be rigidly
fixed to any anatomical landmark such as the A-
point–pogonion line. Instead, the mandibular
incisors should be placed relative to the maxillary
incisors where adequate lip support had been
established.

All cephalometric head films to be taken in the lips
closed position even if the lips are strained to
close.
The various steps involved are,
STEP 1.
OBJECTIVE: To draw fronto nasal area, line BaN and line NA.
Place a clean sheet of acetate paper over the original
cephalometric tracing and copy the frontonasal area -
both hard and soft tissue, tracing through the bridge of
the nose.
Copy the line BaN.
Copy the line NA.

STEP II
OBJECTIVE: To express growth in the frontonasal
area over a two-year period.
a) Superimpose on line BaN and move the VTO
tracing until there is 1.5mm of growth expressed in
the frontonasal area
b) Holding the VTO tracing in the position as in
above, copy the Ricketts facial axis (foramen
rotundum to Gnathion).

STEP III.
OBJECTIVE: To express 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.
a) Superimpose the V.T.0 Facial axis along the
original facial axis. Move the V.T.0 tracing
upwards so that the V.T.0 BaN line is above the
original BaN line, the distance between these
lines should be three times the amount of growth
expressed previously in the frontonasal area.

b) Holding this position, copy the anterior
portion of the mandible to include the
symphysis, anterior 1/3 of lower border of
the mandible and Downs’ mandibular plane
c) Draw soft tissue chin from its anterior most
point, extending this line posteriorly. Eliminate
any evident hyper tonicity (mentalis action) by
rounding out this area.

STEP IV
 OBJECTIVE: To express growth in a
horizontal direction in the mandible (or
lower face) and draw the posterior border
of the mandible
a) Superimpose on mandibular plane and
move the V.T.O. forward until the
original and V.T.O. foramina rotundae
are vertically aligned.
b) With the tracing in this position the posterior
border and ramus of the mandible is drawn

 STEP V.
 OBJECTIVE: To locate and draw the maxilla, and
lower half of nose.
a) Superimpose the V.T.0 NA line on the original
NA line and move the V.T.0 up until the vertical
growth expressed above the BaN line and below
the mandibular plane is in the ratio of 40:60. In
other words, there is 40% of total vertical growth
above the BaN line and 60% below the mandibular
plane.
b) 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.

c)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

STEP VI.
OBJECTIVE: To locate and draw the occlusal
plane.
a) With the V.T.0 super imposed on line NA move
the V.T.0 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.
b) With the tracing in this position copy the
occlusal plane.

STEP VII
OBJECTIVE: To determine the soft tissue lip
contour using the “new” Holdaway line (H-
Line).
The “Lip Contour Template” may be usefully
employed as an aid in the location of the H-line.
Dr Holdaway’s studies have shown that in
“ideal” profiles, the distance between the depth
of the upper lip contour and the H-line is
between 3 and 7 millimeters.

Clinically judge the length of the upper lip.
For short lips, use a 3 mm sulcus depth and
a 7 mm sulcus depth for long lips. In lips of
AVERAGE length a sulcus depth of 5mm is
used. Having judged the lip length, use the
“Lip Contour Template” to locate the H-line

USE OF TEMPLATE
a) Judge the upper lip length to determine the
most suitable lip contour profile for the patient.
b) With the lower end of the H-line tangent to the
chin soft tissue contour, slide the template up or
down until the lip embrasure is located 3mm
above the occlusal plane.
c) Maintaining the lower end of the H-line tangent
to the chin contour, move the upper end of the
template forward or backward until a desirable,
balanced
and aesthetically “ideal” soft tissue profile contour is
obtained.

d) Pencil a point in the centers of the circles at the top
and
bottom ends of selected template H-line.
e) Joining the penciled points will provide the location
of the H-line.
f) Having determined the location of the H-line, the
position of the lip embrasure and the upper lip sulcus
depth, artistically draw the upper and lower lip
contours.
The upper lip should just touch the H-line, whereas the
lower lip should lie approximately ½mm anterior to this
line.

STEP VIII
OBJECTIVE: To relocate maxillary central incisor
PRINCIPLES:
1) Lip strain— Dr Holdaway contends that 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

2) 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.
3) Maxillary Incisor Rebound— generally, during post treatment
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 theV.T.0. Tracing on the NA line and the maxilla and trace
in the maxillary incisor, taking cognizance 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.

STEP IX.
OBJECTIVE: To reposition lower incisor and calculate
resultant arch length change.
1) Having located the position of the upper incisor, judge the
position and axial inclination of the lower incisor
2) 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.

STEP X.
OBJECTIVE:
To reposition lower first molar, use the plaster casts to
determine arch length discrepancy due to crowding and/or
rotation.
Superimpose tracing on mandibular plane and register on
symphysis.
Incisor repositioning was 2mm lingually, thus effectively
decreasing lower arch length 4mm

STEP XI.
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

STEP XII.
OBJECTIVE: To complete artwork
1) ANS to upper incisor
2) Anterior portion of hard palate.
3) Lower alveolus lingually and labially.

The mini visualized treatment objective was described by
“MAGNESS” in 1987; it is a simple yet relatively
accurate method of predicting the incisor and molar
relations on the basis of growth and treatment alteration
of the dentoskeletal framework. Obtainable treatment
objectives are recorded on the original acetate tracings.
In addition to space calculation, direction and magnitude
of tooth movement are clearly indicated. It is an excellent
visual aid during case presentation and may also be used
to check on possible “midcourse” corrections during
treatment and the evaluation of the final result compared
with the original prediction.

*Weakness of manual prediction :-
1) Variability in lip thickness.
2) Degree of lip version
3) Lip tonicity
4) Methods are more cumbersome &
time consuming.

*To overcome the limitations of manual prediction –
computers moved into orthodontic practice environment.
Ricketts advocated the use of computers to predict growth
because of the time required to compare, organize & sort the
data & then retrieve the information in a clinically useful form.
He also stressed the need for individualizing the
measurements according to age, sex, ethnic type & degree of
maturation of each patient.

There are basically 2 types of surgical vto’s. They are
1) Orthodontic – Surgical VTO
2) Surgical VTO
The orthodontic- surgical VTO is used for overall
treatment planning & illustrates the effect of both
orthodontic tooth movement & surgical skeletal
changes.
The surgical prediction is performed immediately before
surgery to plan the specific surgical movements. They
include no dental changes other those to be produced by
surgery.

Reasons for performing Ortho-surgical VTO
1) To assess accurately the profile esthetic results of
proposed surgery & orthodontics.
2) To determine the desirability of adjunctive surgical
procedures like genioplasty.
3) To help determine the sequencing of surgery &
orthodontics.
4) To help determine if extractions are necessary & to
determine which teeth to extract if extraction is
necessary.
5) To determine the anchorage requirements.

For the surgical – orthodontic patients, the treatment plan is
constituted based on predictions made on the radiograph
& the cast.
The types of predictions are
a) Cephalometric prediction: - allows direct evaluation of
both dental & skeletal movements.
b) Cast predictors:- show in detail the dental relationships
that indirectly reflect the underlying skeletal changes.

Cephalometric prediction
Manual Computer
Overlay
tracing
method
Template
method
Software
programmes
only
Software
programme & video
imaging

Manual methods
Tracing overlay:-
It’s the simplest way to simulate the effects of mandibular
surgery. The final prediction tracing is produced without any
intermediate tracings.
This procedure is limited to surgery that does not affect the
vertical position of the maxilla.

Steps in Overlay Tracing
1) The film is traced, all the teeth( especially the occlusal
surfaces) are to be traced.
2) A new sheet is to be placed over the existing traced one
& structures that will not be changed by the mandibular
surgery are traced.

The structures not changed are,
a) Cranial base,
b) Maxilla & mandibular teeth
c) Mandibular ramus down to the angle
d) Soft tissue profile down to the base of the nose.
*** mandible or soft tissue below the nose is not traced.

3) The overlay tracing to be slid so that mandibular teeth can
be seen through it in their desired post surgical position &
trace the lower teeth & jaw.
4) The overlay tracing is superimposed on the cranial base to
measure how far the lower has moved froward. Lower lip
will go forward 2/3rd as far, mark is made at that distance.
5) Superimpose again on the mandible, soft tissue chin to be
drawn & lower lip outline to be completed through the
marked point.
6) Superimpose again on the cranial base & the soft tissue
profile to be completed.

Advantages of Overlay tracing
1) Dental casts are made available when cephalometric
predicitons are carried out.
2) If major orthodontic tooth movement is anticipated
before surgery, so that the orientation of the incisor
teeth will change, it helps to have this simulated on
dental casts in the form of orthodontic diagnostic
setup.

Template method
The use of templates for intermediate tracings between the
original & final prediction tracing is mandatory,
a) When the major movements of the teeth must be
simulated.
b) When the maxilla will be repositioned vertically
c) When the chin is repositioned
d) Only when the mandible is being moved.

Advantages:-
They can be used for any type of prediction.
Disadvantage:-
More time consuming to prepare a template.
Typical templates are made for the entire maxilla if a 1 or 2 piece maxillary
osteotomy is planned.
In cases wherein 3 piece maxillary osteotomy is planned, an anterior &
posterior template have to be made.
The posterior template would have to show ,
Posterior nasal spine till the second premolar
While the anterior segment includes ANS, bony contour through point A &
lingual contour of the alveolar process behind the incisors.

In the mandibular arch, the template
includes the mandibular teeth & the
entire outline of the mandible.
The templates should be in different
color from the original tracing so
that it would be easy to interpret.

Surgical procedure for mandibular
enhancement
1) The desired facial depth is indicated on the tracing.

Step 2:-
The prediction is began by tracing the distal portion of the
mandible, soft tissue chin, & the occlusal plane on a clean
piece of acetate.

Step 3:-
Slide the prediction forward along the chosen occlusal plane
until bony pogonion lies on the line indicating the desired
facial depth.

Step 4:-
Trace the fixed structures.

Step 5:-
Draw the A-Pogonion line & the facial axis on the prediction.
These line are used to place the teeth in their ideal positions.

Step 6:-
Place the lower incisor in its ideal position ( wherein the
incisal edge is 1mm ahead of the A-PO line & long axis at 22
degrees to the A-PO line.

Step 7:-
Superimpose the distal mandible of the prediction on that of
the tracing. The change in position of the lower incisor is to
be noted at this time.
The amount of space required for axial inclination correction of the
lower incisor is to be noted at this time, and the total arch length
discrepancy is measured.

Step 8:-
The total arch length discrepancy amount is subtracted from
the width of the tooth to be extracted, the remainder of the
space is to be closed by bringing the molars forward.
Molar is placed on the occlusion plane & advanced half the
amount o f the extraspace.

Step 9:- place the upper molar in ideal class 1 occlusion.
The upper incisor is placed in an ideal overbite & overjet
Relationship with the long axis 5 degrees more upright than
the new facial axis.
The soft tissue profile is completed.

Step 10:-
Superimpose the prediction on the fixed structures of the
tracing & note the changes.
Antero-posteriorly upperlip vermillion will change in same
direction as upper incisor movement, but only 2 half
distance. Subnasale is not affected by dentall changes, so
new lip is drawn in appropriate position & connected to
subnasale by smooth curve.

Step 11:-
To indicate appropriate lip thickness, draw a dashed line on
the tracing.

Step 12:- prediction to be laid on the tracing so that the lower
lip on the tracing touches
a) Upper lip
b) Incisal edge of upper incisor
c) Labial surface of the lower incisor.
The vermilion border of the lip to be traced.

Step 13:-
Connect the lip to the soft tissue chin with a smooth curve
to complete the tracing.

Computer Imaging :
The use of computer imaging simulated the probable
treatment outcomes such as results of dental
compensation or surgical orthodontic correction, which
could facilitate communication about these alternatives
by eliminating misconceptions. Full disclosure of the
consideration of all valuable treatment alternatives had a
great benefit from a risk management standpoint in
addition to their bioethical merits.

Video imaging is another recent advancement in the field of
orthodontic diagnosis. According to Turpin (1995) - orthodontist is
generally influenced more by the objective findings whereas
patient is guided by subjective issues. Orthodontic treatment
planning is becoming an interactive process in which the patient
and the parent are acting as co- decision makers. New and more
effective tools are needed to help make such an important
decision. One such tool is computerized video imaging. He
concluded that computer imaging is the prediction and reporting of
dental and facial changes. Describing the potential changes to the
lay person has always been difficult. Practitioners frequently resort
to the use of another patient’ records as an example. In reality the
other patient may have little in common with the person whose
treatment is being planned. Computer imaging provides a new tool
for describing soft tissue changes.

According to Sarver (1996) computerized video imaging fits in this
time proven treatment planning scenario. Video imaging
technology allows the orthodontist to gather frontal and profile
images and modify them to project overall esthetic treatment
goals. In the course of surgical treatment, patients are very
motivated to know what they will look after surgery. Profile line
rendering may represent a reasonable feedback system for the
orthodontist but has little cognitive value to the patients. It is
possible to cut photographs and move the sections in a way that
some what simulates the surgical outcome but does not allow the
planner to visualizes limiting factors such as the dental relationship
or differential soft tissue reaction to hard tissue movements. Gaps
in manipulated photographs are unavoidable.

The use of video imaging technology allows us to modify facial
images to project treatment goals and then discuss them with the
patient. Video imaging is mush easier for a patient to
comprehend than just the soft tissue profile of cephalometric
tracings. Video imaging has the potential to touch almost every
aspect of orthodontic practice, diagnosis and treatment planning,
communication at consultation, database management,
integration with practice management programmes, and many
other areas that have not been fully realized yet.

COMPUTER PREDICTION
The first step in using a computer program for cephalometric
prediction is to enter a digital model of the patient’s tracing into
computer memory. Even though the details of the digital model vary
among the several currently available software programs the
number of coordinate points (x,y) to represent the tracing are only
limited. The more, the number of points to be digitized, the more
time it takes to enter the tracing into the computer.
Once an adequate digital model has been created, most computer
programs operate quite analogously to the template method and
key or mouse is used for moving the electronic template to a new
position. Different surgical procedures can be depicted by moving
the templates.

The computer method has two major advantages
(1) the software programs have automatic adjustments in the
soft tissue profile, or which speeds up the prediction process
and makes it more consistent and another advantage
(2) is with the digital model in computer memory, it is easy to
produce several slightly different cephalometric predictions.
Therefore the more predictions that are made the more
advantageous it is to have the cephalometric data in an
appropriate digital model
(3) it also helps to integrate information from the dental casts
with the cephalometric information.

RELIABLITY OF COMPTER PREDICTION
Much attention has been devoted to facial esthetics,
harmony, and balance as they relate to orthodontics. In
essence, well proportioned and balanced soft tissue facial
contours presuppose well defined underlying skeletal and
dental structures.
Many claim that correct positioning of the incisors allows the
overlying soft tissues to be in balance and in harmony. The
positioning of the mandibular incisors in particular has been
cited as being the key to orthodontic diagnosis and treatment
planning, because of its effects on esthetics. This is only a
hypothesis.

The determination of facial balance for the particular
individual being treated as judged from a two dimensional
lateral head film tracing is subjective and at best only an
estimate.
So a video imaging or VTO of what a patient may look like
after orthodontic treatment should have a written disclaimer
placed on the print out, lest the patient perceive that the VTO
is a guaranteed result.

CONCLUSION
The V.T.O forecast is a valuable tool
for the orthodontist (with regards to
his self improvement), which permits
him to set his / her goals well in
advance for better comparison with
the results which they obtain at
the end of the treatment programme.

Visualized Treatment Objective.ppt

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