Holdaway’s soft-tissue VTO

Holdaway’s soft-tissue VTOHoldaway’s soft-tissue VTO
• Purpose is to establish a balanced profile andPurpose is to establish a balanced profile and
pleasing facial esthetics and to evaluate thepleasing facial esthetics and to evaluate the
orthodontic correction necessary to achieve thisorthodontic correction necessary to achieve this
goalgoal
• Holdaway VTO emphasizes soft tissue profileHoldaway VTO emphasizes soft tissue profile
balancebalance
www.indiandentalacademy.com

• Growth of the cranio-facial skeleton is predicted forGrowth of the cranio-facial skeleton is predicted for
the estimated treatment time, and the soft tissuethe estimated treatment time, and the soft tissue
profile between the nose and the chin arranged toprofile between the nose and the chin arranged to
create an “ideal” facial profile for the individualcreate an “ideal” facial profile for the individual
patientpatient
• Maxillary and mandibular incisors are repositionedMaxillary and mandibular incisors are repositioned
to eliminate lip strainto eliminate lip strain
• Allowance is made for probable post treatmentAllowance is made for probable post treatment
““incisor reboundincisor rebound””
• Maxillary teeth are positioned first, and then lowerMaxillary teeth are positioned first, and then lower
incisors are repositioned to be in harmony with theincisors are repositioned to be in harmony with the
upper incisorsupper incisors

• Following the repositioning of the mandibularFollowing the repositioning of the mandibular
incisors, the resultant arch length discrepancyincisors, the resultant arch length discrepancy
may be calculated to determine whether or notmay be calculated to determine whether or not
teeth should be extractedteeth should be extracted

• The VTO is thus a dynamic cephalometricThe VTO is thus a dynamic cephalometric
analysis which takes into account both growthanalysis which takes into account both growth
and biomechanics, thus achieving its aim ofand biomechanics, thus achieving its aim of
being a Visualized Treatment Objectivebeing a Visualized Treatment Objective
• It outlines a goal from the inception ofIt outlines a goal from the inception of
treatment and may be usefully employed intreatment and may be usefully employed in
monitoring growth and treatment progressmonitoring growth and treatment progress

• In sum, therefore the VTO accomplishes :In sum, therefore the VTO accomplishes :
Predicts growth over an estimated treatment time,Predicts growth over an estimated treatment time,
based on the individual morphogenetic patternbased on the individual morphogenetic pattern
Analyzes the soft tissue facial profileAnalyzes the soft tissue facial profile
Graphically plans the best soft tissue facial profileGraphically plans the best soft tissue facial profile
for the particular patientfor the particular patient
Determines favorable incisor repositioning, based onDetermines favorable incisor repositioning, based on
an “ideal” projected soft tissue facial profilean “ideal” projected soft tissue facial profile

Assists in determining total arch lengthAssists in determining total arch length
discrepancy when taking into accountdiscrepancy when taking into account
“cephalometric correction”“cephalometric correction”
Aids in determining between extraction andAids in determining between extraction and
nonextraction treatmentnonextraction treatment
Aids in deciding which teeth to extractAids in deciding which teeth to extract
Assists in planning treatment mechanicsAssists in planning treatment mechanics
Surgery vs. non-surgerySurgery vs. non-surgery
It provides a visual goal or objective for which toIt provides a visual goal or objective for which to
strive during treatmentstrive during treatment

OJECTIVE : To draw frontonasal area, lineOJECTIVE : To draw frontonasal area, line
BaN and line NABaN and line NA

OBJECTIVE : To express growth in the frontonasalOBJECTIVE : To express growth in the frontonasal
area over a two-year periodarea over a two-year period
Super impose on line BaN and move the VTO untilSuper impose on line BaN and move the VTO until
there is 1.5 mm growth in the fronto nasal areathere is 1.5 mm growth in the fronto nasal area
Holding the VTO tracing in the position copy theHolding the VTO tracing in the position copy the
Ricketts facial axisRicketts facial axiswww.indiandentalacademy.com

OBJECTIVE : To express growth in a verticalOBJECTIVE : To express growth in a vertical
direction in the mandible, and to draw the anteriordirection in the mandible, and to draw the anterior
portion of the mandible, soft tissue chin and theportion of the mandible, soft tissue chin and the
mandibular plane of Downsmandibular plane of Downs
Superimpose the VTO facial axis along the original facial axis.Superimpose the VTO facial axis along the original facial axis.
Move the VTO tracing upwards so that the VTO BaN line isMove the VTO tracing upwards so that the VTO BaN line is
above the original BaN line, the distance between these linesabove the original BaN line, the distance between these lines
should be three times the amount of growth expressed in theshould be three times the amount of growth expressed in the
frontonasal areafrontonasal area

OBJECTIVE : To express growth in a horizontal direction inOBJECTIVE : To express growth in a horizontal direction in
the mandible and draw the posterior border of the mandiblethe mandible and draw the posterior border of the mandible
Move the VTO forward until the original and VTO foramenMove the VTO forward until the original and VTO foramen
rotundae are vertically alignedrotundae are vertically aligned

OBJECTIVE : To locate and draw the maxilla, andOBJECTIVE : To locate and draw the maxilla, and
lower half of the noselower half of the nose
Super impose the VTO NA line on the original NASuper impose the VTO NA line on the original NA
line and move the VTO up until the vertical growth isline and move the VTO up until the vertical growth is
expressed above the BaN line and below theexpressed above the BaN line and below the
mandibular plane is in the ratio of 40:60mandibular plane is in the ratio of 40:60

OBJECTIVE : To locate and draw the occlusal planeOBJECTIVE : To locate and draw the occlusal plane
With the VTO superimposed on line NA, move the VTOWith the VTO superimposed on line NA, move the VTO
tracing so that the vertical growth between the maxilla and thetracing so that the vertical growth between the maxilla and the
mandible is expressed as being 50% above the maxilla andmandible is expressed as being 50% above the maxilla and
50% below the mandible50% below the mandible

OBJECTIVE : TO determine the soft tissue lipOBJECTIVE : TO determine the soft tissue lip
contour using the Holdaway linecontour using the Holdaway line

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

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

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

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

A statistical evaluation of theA statistical evaluation of the
Ricketts and Johnston growth-Ricketts and Johnston growth-
forecasting methodsforecasting methods

• Four methods of growth forecasting were comparedFour methods of growth forecasting were compared
– Johnston forecast gridJohnston forecast grid
– Ave. increments from sella-nasionAve. increments from sella-nasion
– Ricketts short-range predictionRicketts short-range prediction
– Computer forecastComputer forecast
• Objective was to predict the final position of theObjective was to predict the final position of the
points A, Pogonion, end of the nose, lower molarpoints A, Pogonion, end of the nose, lower molar
and point Xi with respect to cranial reference linesand point Xi with respect to cranial reference lines

• The Johnston forecastThe Johnston forecast
gridgrid

• Errors were squared, summed, and divided byErrors were squared, summed, and divided by
the number in the sample to get the mean-the number in the sample to get the mean-
square error. Square root was taken for the rot-square error. Square root was taken for the rot-
mean-squared errormean-squared error
• 70% of the predictions will be within ±1 rms70% of the predictions will be within ±1 rms
errorerror
• 95 % will be within ±2 rms error95 % will be within ±2 rms error

• Ave. increments from sella-nasionAve. increments from sella-nasion
To study points not included in JohnstonTo study points not included in Johnston
forecast grid, as well as grid’s applicability to a 10-forecast grid, as well as grid’s applicability to a 10-
year growth periodyear growth period
Average increments for each of the points underAverage increments for each of the points under
consideration were calculated from SN with S asconsideration were calculated from SN with S as
the origin, and these increments were then usedthe origin, and these increments were then used
in a prediction as follows: Using sella-nasion as ain a prediction as follows: Using sella-nasion as a
horizontal axis with sella as its center, ave.horizontal axis with sella as its center, ave.
increments per year were addedincrements per year were added

• Girls - 15 yearsGirls - 15 years
• Boys - 19 yearsBoys - 19 years

• The Ricketts short-The Ricketts short-
range predictionrange prediction

• Computer forecastComputer forecast
Individual growth curves are used for the mandible,Individual growth curves are used for the mandible,
maxilla, and cranial base rather than using the samemaxilla, and cranial base rather than using the same
increments for every age groupincrements for every age group
Abnormal growth with RMDS data bankAbnormal growth with RMDS data bank

Patients who grow abnormally large mandibles with less
growth in the cranial base – abnormal Class III patterns

Unusually strong patterns which rotate forwardUnusually strong patterns which rotate forward

Abnormally weak facial patterns – they rotate distallyAbnormally weak facial patterns – they rotate distally

ResultsResults
Johnston gridJohnston grid
Least accurateLeast accurate
It was accurate as any for predicting the noseIt was accurate as any for predicting the nose
64 percent accurate for Point A64 percent accurate for Point A
70 percent accurate on Pogonion70 percent accurate on Pogonion

S-N average incrementsS-N average increments
Improvement over the Johnston grid at bothImprovement over the Johnston grid at both
Pogonion and point APogonion and point A

Ricketts short-range prediction methodRicketts short-range prediction method
Less rms error than Johnston grid or SN average incrementsLess rms error than Johnston grid or SN average increments
Some of the smaller over-all error was due to the fact thatSome of the smaller over-all error was due to the fact that
point CC, the origin of this growth prediction, is closer topoint CC, the origin of this growth prediction, is closer to
Pogonion than to SellaPogonion than to Sella
10 to 20 percent improvement of this method over average10 to 20 percent improvement of this method over average
incrementsincrements

RMDS computer programRMDS computer program
Based on theories of RickettsBased on theories of Ricketts
Individualized further by using growth rates variable for theIndividualized further by using growth rates variable for the
patient’s age and by recognising unusual facial patternspatient’s age and by recognising unusual facial patterns
Most accurate of the four methodsMost accurate of the four methods
 21% more accurate than Ricketts21% more accurate than Ricketts
 56% more accurate than Johnston grid56% more accurate than Johnston grid

If the actual growth was far different from theIf the actual growth was far different from the
predicted growth, the records were often returned topredicted growth, the records were often returned to
the laboratory so that a file of “abnormal growth “the laboratory so that a file of “abnormal growth “
could be compiledcould be compiled
A consistent type emerged – one which grew more inA consistent type emerged – one which grew more in
the mandible and less in the cranial base than predictedthe mandible and less in the cranial base than predicted
Prediction of abnormal growth inPrediction of abnormal growth in
Class III malocclusionsClass III malocclusions

• The three most consistent measurements whichThe three most consistent measurements which
deviated from the normal in these patients weredeviated from the normal in these patients were
ramus position, porion location and cranialramus position, porion location and cranial
deflectiondeflection
• Predictor measurementsPredictor measurements
• Hokkaido University Orthodontic DepartmentHokkaido University Orthodontic Department

• For cranial deflection, porion location andFor cranial deflection, porion location and
ramus position the greater the value, the moreramus position the greater the value, the more
likely the patient is hypothesized to have a Classlikely the patient is hypothesized to have a Class
III growth patternIII growth pattern
• With molar relation, the lesser the value, theWith molar relation, the lesser the value, the
more likely the patient is to have a Class IIImore likely the patient is to have a Class III
malocclusionmalocclusion

Clinical normClinical norm
(CN)(CN)
StandardStandard
DeviationDeviation
Cranial deflectionCranial deflection 2828 3.03.0
Ramus positionRamus position 75.575.5 2.82.8
Porion locationPorion location 3737 2.52.5
Molar relationMolar relation -3.0-3.0 2.62.6

Amount of abnormality, or deviation is calculatedAmount of abnormality, or deviation is calculated
by :by :
V-CNV-CN
SDSD

• Cephalometric analysis was conducted at baseline and 7Cephalometric analysis was conducted at baseline and 7
years for 40 children (20 girls, 20 boys) who received noyears for 40 children (20 girls, 20 boys) who received no
orthodontic treatment. Ricketts’ long-range predictionorthodontic treatment. Ricketts’ long-range prediction
was performed from baseline cephalograms andwas performed from baseline cephalograms and
compared with actual growth 7 years later. Twenty-onecompared with actual growth 7 years later. Twenty-one
cephalometric (12 angular and 9 linear) parameters werecephalometric (12 angular and 9 linear) parameters were
measured on actual and predicted tracings. The Pearsonmeasured on actual and predicted tracings. The Pearson
correlation coefficient was used to evaluatecorrelation coefficient was used to evaluate
relationships between the “predicted” and “actual”relationships between the “predicted” and “actual”
measurements.measurements.
• There was a higher level of correlation for growthThere was a higher level of correlation for growth
prediction in girlsprediction in girls
Evaluation of Ricketts’ long-range growthEvaluation of Ricketts’ long-range growth
prediction in Turkish childrenprediction in Turkish children

• The baseline average age was 9.2 ± 0.82 years for girlsThe baseline average age was 9.2 ± 0.82 years for girls
and 9.3 ± 0.92 years for boysand 9.3 ± 0.92 years for boys
• Linear measurements: 1, Convexity; 2, Condylion-PointLinear measurements: 1, Convexity; 2, Condylion-Point
A; 3, Condylion-Gnathion; 4, Lower lip to E plane; 5,A; 3, Condylion-Gnathion; 4, Lower lip to E plane; 5,
Upper lip length; 6, Cranial length (anterior) (CC-Na);Upper lip length; 6, Cranial length (anterior) (CC-Na);
7, Ramus height (CF-Go); 8, Porion to PTV; 9, Corpus7, Ramus height (CF-Go); 8, Porion to PTV; 9, Corpus
length (Xi-Pm).length (Xi-Pm).
• Angular measurements: 1, Lower face height; 2,Angular measurements: 1, Lower face height; 2,
Nasolabial angle; 3, Facial depth; 4, Facial axis; 5,Nasolabial angle; 3, Facial depth; 4, Facial axis; 5,
Maxillary depth; 6, Maxillary height; 7, Palatal plane-FHMaxillary depth; 6, Maxillary height; 7, Palatal plane-FH
plane; 8, Mandibular plane-FH plane; 9, BNA angle; 10,plane; 8, Mandibular plane-FH plane; 9, BNA angle; 10,
Cranial deflection; 11, Ramus-Xi position; 12,Cranial deflection; 11, Ramus-Xi position; 12,
Mandibular arc angle.Mandibular arc angle.

Ricketts’ long-range growth prediction applied toRicketts’ long-range growth prediction applied to
Turkish children showed statistically significantly higherTurkish children showed statistically significantly higher
correlations between predicted and actualcorrelations between predicted and actual
measurements in:measurements in:
• Convexity, lower face height, condylion, point A, upperConvexity, lower face height, condylion, point A, upper
lip length, facial depth, facial axis, palatal plane-FHlip length, facial depth, facial axis, palatal plane-FH
plane angle, mandibular plane-FH plane angle, ramusplane angle, mandibular plane-FH plane angle, ramus
height, and mandibular arc angle in girlsheight, and mandibular arc angle in girls
• Lower face height, nasolabial angle, porion to PTV,Lower face height, nasolabial angle, porion to PTV,
ramus-Xi position, cranial deflection, condylion-pointramus-Xi position, cranial deflection, condylion-point
A, lower lip-E plane, facial axis, BNA angle, andA, lower lip-E plane, facial axis, BNA angle, and
mandibular arc angle in boys.mandibular arc angle in boys.

Holdaway’s soft-tissue VTO

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Holdaway’s soft-tissue VTO