• Share
  • Email
  • Embed
  • Like
  • Save
  • Private Content
Growth  prediction   /fixed orthodontic courses
 

Growth prediction /fixed orthodontic courses

on

  • 510 views

...


The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.


Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
00919248678078

Statistics

Views

Total Views
510
Views on SlideShare
510
Embed Views
0

Actions

Likes
1
Downloads
33
Comments
0

0 Embeds 0

No embeds

Accessibility

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment
  • an <br />

Growth  prediction   /fixed orthodontic courses Growth prediction /fixed orthodontic courses Presentation Transcript

  • GROWTH PREDICTION • • • • • Introduction Definition Uses Methods Limitation www.indiandentalacademy.com
  • INDIAN DENTAL ACADEMY • Leader in continuing dental education • www.indiandentalacademy.com www.indiandentalacademy.com
  • GROWTH PREDICTION • Introduction • • • Scammon’s curve Cephalocaudal gradient Data from various studies Bolton brush study Iowa growth study www.indiandentalacademy.com
  • GROWTH PREDICTION Definition • Assumption of ability to estimate practically future growth. • Asserting on the basis of theory, data or experience but in advance of proof. www.indiandentalacademy.com
  • GROWTH PREDICTION Why it is necessary ? • Helps in diagnosis • Development of satisfactory treatment plan www.indiandentalacademy.com
  • Growth prediction Methods of predicting facial growth change  According Bjork  Computerized prediction methods  Logarithmic spiral  Arcial growth of the mandible  Visual treatment objective • Jacobson and Sadowsky • Ricketts • Holdways www.indiandentalacademy.com
  • GROWTH PREDICTION Methods of predicting facial growth change According Bjork • Longitudinal approach • Metric approach • Structural approach www.indiandentalacademy.com
  • Growth prediction • Longitudinal approach - Tweed on growing pt. 2 lateral ceph. 12-18 months apart 3 categories Type A Type B Type C www.indiandentalacademy.com
  • Growth prediction type A – middle & lower face growth in unison + equal change in vertical & horizontal dime. Type B – middle face > lower face Type C – lower face < middle face www.indiandentalacademy.com
  • Growth prediction Tweed – growth pattern remain constant. - Moore et al - No use in predicting changes. • Limitation Accurate in Retrospective. • Conclusion – Not accurate method. www.indiandentalacademy.com
  • Growth prediction • Metric approach - consist of measuring different structure on a single radiograph & then relating these measurement to future growth changes . Correlation coefficient =r - Association b/w 2 variable - Direction either positive or negative of the relationship - It is used in prediction by Squaring the value of ‘r’ = coefficient of determination ( amount of www.indiandentalacademy.com variation of 2nd variable )
  • Growth prediction • Bjork ,Harvold ,Lande, Solow ,others - Correlation Coefficient not more 0.4 or 0.5 - 16% to 25% variation Conclusion this methods is least clinically siginificant www.indiandentalacademy.com
  • Growth prediction • Structural approach - To predict mandible growth direction - Superimposition on metallic implant - 7 areas 1. Inclination of condyle 2. Curvature of the mandibular canal 3. Inclination of symphysis www.indiandentalacademy.com
  • Growth prediction 4. Shape lower border of 5. 6. 7. the mandible The interincisal angle The interpremolar or molar angle The anterior lower facial height Conclusion This is also least clinically siginificant www.indiandentalacademy.com
  • Growth prediction • Skeiller ,Bjork, and Linde – Hansen • 1. 2. 3. 4. (Tried to quantify it) 4 variable MP inclination - Anterior cranial base (MP:SN) or Ratio of posterior & anterior facial height The intermolar angle Shape of lower border of the mandible (GO - ME to lower border of the mandible) Symphysis inclination (sym. Anterior surface –SN) www.indiandentalacademy.com
  • Growth prediction • Measurement of these variables were included R squar = 0.8612 = 86% variation in direction of mandibular growth • But 86% was high value www.indiandentalacademy.com
  • Growth prediction Methods of predicting facial growth change  According Bjork  Computerized prediction methods  Logarithmic spiral  Arcial growth of the mandible  Visual treatment object www.indiandentalacademy.com
  • Growth prediction • Computerized prediction methods • • 1. 2. Tool of analysis not a method Advantage Facilitates testing Complex formulas to growth prediction www.indiandentalacademy.com
  • Growth prediction • Ricketts 1970 – potential of computerization - Cephalogram (diagnosis ,T/P) • Greenberg & Johnston - Computer forecasts not better than the assumption of average growth - No difference bet. this & method based on simple addition of the average changes. www.indiandentalacademy.com
  • Growth prediction Methods of predicting facial growth change According Bjork Computerized prediction methods Logarithmic spiral Arcial growth of the mandible Visual treatment object www.indiandentalacademy.com
  • Growth prediction • Logarithmic spiral Golden triangles Why  how the position of 3 foramina on the unitary , logarithmic spiral in anterior open bite and deep bite pt. (Melvin. Moss ) www.indiandentalacademy.com
  • Logarithmic spiral www.indiandentalacademy.com
  • Evolution of logarithmic spiral • • • • Sectioning of a line Smaller section is proportional to large section Larger portion is called ‘golden section’ Larger section is Phi / www.indiandentalacademy.com
  • Evolution of logarithmic spiral • Small section is 1 • Larger = 1.618 times • the smaller The smaller is 0.618 the length of the larger www.indiandentalacademy.com
  • Evolution of logarithmic spiral • Phi relationship - Plants, animals, human body , face • Golden progression – series of these proportions - Symbols - 2 3 , , 4 www.indiandentalacademy.com
  • Evolution of logarithmic spiral • Golden triangle • • • Base of a triangle 1.0 Sides of equilateral triangle 1.618 Forms a 72 – 72 -36 degree www.indiandentalacademy.com
  • Evolution of logarithmic spiral • Bisection of one base angle cross the opposite side • Divide that side into a golden section • Form new golden triangle www.indiandentalacademy.com
  • Evolution of logarithmic spiral • Bisection of golden triangle can be made in a series www.indiandentalacademy.com
  • Evolution of logarithmic spiral • Curve used to connect the points on a series of the triangles • Form Logarithmic spiral. www.indiandentalacademy.com
  • Logarithmic spiral • So human mandible grows as a logarithmic spiral on the arc. www.indiandentalacademy.com
  • • • • 1. 2. 3. Logarithmic spiral Melvin Moss Aim - determine the position of 3 foramina on the unitary , logarithmic spiral in anterior open bite and deep bite pt. These conditions can be anticipated at young age even before orthodontic diagnosis Foramen Foramen ovale Mandibular foramen inferior alveolar nerve Mental foramen www.indiandentalacademy.com www.indiandentalacademy.com
  • Logarithmic spiral • Introduction Studied the position of the inferior alveolar nerve • Conclusion These foramina , at all ages fit precisely upon a single mathematically defined logarithmic spiral www.indiandentalacademy.com
  • Logarithmic spiral Foramen “moved” down along this same logarithmic spiral in geometric fashion The gradient of motion directly increasing with the distance of the foramina from cranial base. www.indiandentalacademy.com
  • Logarithmic spiral • Method and materials 2 group of pt. Columbia university University of utah 16 pt - 3 m & 4 f 4 groups (Ant Open bite) 10 pt Normal swallowers -4m&5f 10 pt Tongue thrust (Deep bite) 5 pt Angle II div 1 5 pt Ant open bite www.indiandentalacademy.com
  • Logarithmic spiral • Tracing of cranial base & mandibular outline from films • Superimposed the logarithmic spiral • Position of 3 foramen marked on it. www.indiandentalacademy.com
  • Logarithmic spiral • Result  Singular position of foramen ovale in anterior open bite.  Foramen ovale located farther down the spiral. Help in diagnosis  No sexual dimorphism www.indiandentalacademy.com
  • Logarithmic spiral  Mandibular & mental   foramen also further down the logarithmic spiral in AOB Not as diagnostically unique Distance between these not decreased. www.indiandentalacademy.com
  • Logarithmic spiral  Foramen oval cluster relatively ‘high’ up on the spiral in deep bite. www.indiandentalacademy.com
  • Logarithmic spiral Discussion Mandibular shape - inferior alveolar nerve - 2 factors foramina position on the spiral distance between them. • Fetal & circumnatal periods - All foramina placed near the origin of spiral and nearer to each other - Flatter curvature - Mandible gonial angle relatively obtuse or flat. www.indiandentalacademy.com
  • Logarithmic spiral With growth , all foramina moved down along the spiral and distance • Ramus becomes more erect relatively to corpus • Gonial angle becomes acute www.indiandentalacademy.com
  • Logarithmic spiral • Anterior open bite  Foramen ovale down along the spiral Distance mand. &mental foramen not decrease Course of inferior alveolar nerve flatter  Ramus & corpus more obutse www.indiandentalacademy.com
  • Logarithmic spiral • Deep bite ‘Higher’ up on the spiral  3 neural foramina distance not decreased  Inferior alveolar nerve curvilinear course  Ramus & corpus more acute www.indiandentalacademy.com
  • Logarithmic spiral • Anterior cranial base – Richardson Sella - NA Deep bite Anterior open bite www.indiandentalacademy.com
  • Logarithmic spiral Anterior open bite • Gonial angle Ar –Go-Me Obtuse • Mandibular size Ramus Corpus Shorter Normal length • Anterior cranial base (S-Na) No difference www.indiandentalacademy.com Deep bite Acute No significant linear difference
  • Logarithmic spiral Anterior open bite • Periosteal functional matrix (Massater) Deep bite No difference in attachment site • Capsular functional matrix Oral functioning space Abnormal www.indiandentalacademy.com Normal
  • Growth prediction Methods of predicting facial growth change According Bjork Computerized prediction methods Logarithmic spiral Arcial growth of the mandible Visual treatment objective www.indiandentalacademy.com
  • Principal of Arcial growth of the mandible Robert M. Ricketts • Purpose – explain a method for finding the arcial growth of the mandible and to enumerate some uses of the principal • Based on computer study • Predict long range growth forecast www.indiandentalacademy.com
  • Arcial growth of the mandible • Principal – mandible grows by superioranterior apposition at the ramus on a curve or arc which is a segment formed from a circle. • Radius – Pm to point Eva. www.indiandentalacademy.com
  • Arcial growth of the mandible • Growth of the mandible 1. 2. 3. Roentgenographic cephalometric Bjork Enlow Bjork - variation in the mandibular bending. - Resorption of lower angular border - 3rd molar crypt – stable longitudinal reference Enlow 3D growth pattern Remodeling area Reversal areas of stability www.indiandentalacademy.com
  • Arcial growth of the mandible Prediction of mandibular growth • Primary methods - • • • Long axis of condyle & neck Lower border of mandible ‘Central core’ cephalomertrically Search for ‘reference point’ External mandible (mandibular plane,ramus plane, condyle – symphysis ) www.indiandentalacademy.com
  • Arcial growth of the mandible • Xi point – center of ramus Occlusal plane Entrance of neurotrophic bundles www.indiandentalacademy.com
  • Arcial growth of the mandible • Bisect the height of ramus from the sigmoid notch www.indiandentalacademy.com
  • Arcial growth of the mandible www.indiandentalacademy.com
  • Arcial growth of the mandible • • • • Dc point Condyle axis Corpus axis Change in angle - change in mandibular form • Second method – • Magnitude & angular relation. More successful as a method of forecasting www.indiandentalacademy.com
  • Arcial growth of the mandible • Suprapogonion / Pm Reference point Ricketts – stress center Enlow – site of reversal line Bjork - cosistent www.indiandentalacademy.com
  • Arcial growth of the mandible • The objective of research was still towards finding a method to critically predict future form and size of the mandible over the long range. www.indiandentalacademy.com
  • Arcial growth of the mandible computer study • 5 yrs growth study of mandible & lower dental arch • In lateral & frontal head films -362 measurement www.indiandentalacademy.com
  • Arcial growth of the mandible • • • • • • Material 40 pt – lateral & frontal cephalometric film One group – 8 yrs another group -13 yrs No orth. t/t 20M & 20F 20 – class I with normal occlusion 20 - class II malocclusion www.indiandentalacademy.com
  • Arcial growth of the mandible Findings • Mandible bend ½ • • degree per year. Bending in an orderly manner. Growth arc was operative. www.indiandentalacademy.com
  • Arcial growth of the mandible • To determine the true arc of growth of the mandible • First arc – Pm ,Xi ,Dc • Straightening of the mandible www.indiandentalacademy.com
  • Arcial growth of the mandible • Second arc - tip of coronoid , R1 , Pm • Segment of circle small in radius. • Excessive bending of mandible www.indiandentalacademy.com
  • Arcial growth of the mandible • True arc – • • • Condylar & Coronoid process , Ramus center & it’s ant. Border Radius increase or changing with the size of the mandible Changing arc or ultimate spiral would result. Growth could not be represented as simple segment of circle www.indiandentalacademy.com
  • Arcial growth of the mandible Stress lines • 850 yrs. Old mandible – • • William B. Downs Disintegration of interprismatic subs. Stress lines in the outer & inner plates www.indiandentalacademy.com
  • Arcial growth of the mandible • Examination of stress lines / lateral surface Convergence at protuberance menti Upward ,backward & outward from EO Gnarled area at the coronoid base. www.indiandentalacademy.com
  • Arcial growth of the mandible • Stress line /medial side  Mylohyoid ridge  YM /Y-shaped bony prominence - Center of quadrant of ramus - Inner & outer cortical tables showed confluence  TP/ Triangular plane – Nutritive foramina www.indiandentalacademy.com
  • Arcial growth of the mandible • 2 new point - Eva &TR • Eva- forking of stress lines in ramus • TR /true radius – center of circle from Pog through Eva • Mu point www.indiandentalacademy.com
  • Arcial growth of the mandible • Mandible size increased, increment added to the arc at the sigmoid notch. • Predicted mandible was almost absolutely correct in size and form when compared with the final composite www.indiandentalacademy.com
  • Arcial growth of the mandible • Mandible growth occurs on a arc • This method proved extremely accurate in 50 treated cases which were predicted and compared for periods of as long as 14 yrs later. www.indiandentalacademy.com
  • Arcial growth of the mandible • Amount of growth to forecast on the arc - 2.5 yearly increase 14.5 F & 19M • Symphysis lower border – 1mm each 8 yrs / M www.indiandentalacademy.com
  • Arcial growth of the mandible • Coronoid & condylar process – different • Coronoid – 0.8mm/yr • Condylar 1. 2. 3. - variable Short & weak – 0.0mm Long condyles – 0.4mm/yr Average – 0.2mm /yr www.indiandentalacademy.com
  • Arcial growth of the mandible • Gonion angle growth 50% of the total increase in mandibular growth • Females - no further addition • Males – above +0.2mm www.indiandentalacademy.com
  • Arcial growth of the mandible • External oblique ridge 0.4mm/yr. • RR point – stable bone Ramal width www.indiandentalacademy.com
  • Arcial growth of the mandible • Impaction of third molar and Arcial growth prognosis –25 adult skull normal occlusion 1. Lower third molar 50 % ahead the EOR 50% favorable prognosis 2. Mesial to the EOR – 100 % favorable prognosis 3. Distal to the EOR – poorer 45 % of the nonextracted cases required third molar extraction. www.indiandentalacademy.com
  • Arcial growth of the mandible • Bisect the height of ramus from the sigmoid notch down to the lower border in a perpendicular plane from FH ,then bisected the width of the mandible called XI point www.indiandentalacademy.com
  • Arcial growth of the mandible www.indiandentalacademy.com
  • Arcial growth of the mandible • Xi point – center of ramus Occlusal plane Entrance of neurotrophic bundles www.indiandentalacademy.com
  • Arcial growth of the mandible • 2 new point - Eva &TR • Eva- forking of stress lines in • • ramus A center of upward & forward quadrant of ramus By bisecting R2 & R3 point • TR /true radius – center of circle from Pog through Eva • Mu point www.indiandentalacademy.com
  • Arcial growth of the mandible • Class III The amount of mandibular growth in the forecast is one sixth more in the classIII www.indiandentalacademy.com
  • Arcial growth of the mandible • May be occur in closed bite faces www.indiandentalacademy.com
  • Growth prediction Methods of predicting facial growth change According Bjork Logarithmic spiral Arcial growth of the mandible Computerized prediction methods Visualized treatment objective www.indiandentalacademy.com
  • Visualized treatment objective • • • • • Definition Uses Jacobson and Sadowsky Ricketts Holdways www.indiandentalacademy.com
  • Visualized treatment objective • Definition It is a visual plan to forecast the normal growth of the pt and the anticipated influences of treatment , to establish the individual objectives we want to achieve for that pt www.indiandentalacademy.com
  • Visualized treatment objective • Uses 1. 2. 3. Predict growth over an estimated T/t time Analyzes the soft tissue facial profile Determines favourable incisor repositioning based on an ‘ideal’ projected soft tissue profile 4. Determines total arch length discrepancy www.indiandentalacademy.com
  • Visualized treatment objective 5. Aids in determining b/w extraction & nonextraction treatment 6. Surgical orthodontic correction www.indiandentalacademy.com
  • Visualized treatment objective • • • Jacobson and Sadowsky Ricketts Holdways www.indiandentalacademy.com
  • Visualized treatment objective ALEX JACOBSON & P.LIONEL SADOWSKY • All cephalometric headfilms to be taken in the lips closed position even if they are strained to close • Construct a VTO by considering average growth for an estimated 2 yr period of active t/t & the objective we want to achieve with our mechanics www.indiandentalacademy.com
  • Visualized treatment objective • • • • • • • • • • • Cephalometric tracing for VTO Anterior & posterior cranial base Pterygomaxillary fissure Orbit Anterior outlines of frontal bone Nasal bone & Nasion ANS &PNS ,hard palate Upper central incisor & it’s alveolar process Mandible External auditory meatus Soft tissue profiles www.indiandentalacademy.com Upper & lower molar
  • Visualized treatment objective • • • • • • • • Cephalometric tracing for VTO BAN (Basion-nasion line) Line Na - POINT A F H PLANE Occlusal plane Downs mandibular plane Facial axis Holdway’s line Facial plane www.indiandentalacademy.com
  • Visual treatment objective Step of VTO • Step 1 obj. – To draw frontonasal area , BAN & NA line. • Step 2 obj. – Growth in frontonasal area over 2 yr. - Frontonasal area 1.5 mm growth - 1/4mm per year ( Dr. Holdway’s studies ) www.indiandentalacademy.com
  • Visual treatment objective • Step 3 object – Mandible growth in vertical direc. - Ant. Portion of mandible - Soft tissue chin - Down’s mandibular plane • Superimpose on the facial axis • The distance b/w VTO & ceph Ban line should be 3 times the amount of growth expressed previously in FN area www.indiandentalacademy.com
  • Visual treatment objective Step 4 obj. – Mandible growth in horizontal direction. - Draw the Post border of mandible • Forward growth at chin point = Nasion • Total vertical facial height as well as forward location of chin established www.indiandentalacademy.com
  • Visual treatment objective Step 5 obj. – To locate maxilla & lower half of nose • • • Superimpose on NA line & move up There is 40% of total vertical growth above BaN line & 60% below mandible Nose growth 1mm/year. Step 6 obj. – To locate and draw the occlusal plane • Superimpose on NA plane • Vertical growth is 50% above maxilla & 50% below mandible www.indiandentalacademy.com
  • Visual treatment objective Step 7 obj. – To determine soft tissue lip contour using the new H-line • The distance b/w upper lip contour & H-line is 3 - 7mm (Dr. Holdway’s studies ) www.indiandentalacademy.com
  • Visual treatment objective • Step 8 obj. – To relocate the maxillary central incisor Upper lip thickness = Basic upper lip thickness ( within 1 mm ) • Lip strain is difference b/w above measurement • Maxillary incisor rebound - 0.5mm in class I - 1.5 mm in class II In this case Lip strain = 4 mm Lip movement = 4 mm Maxillary incisor rebound = 1.5 mm Total 9.5 mm www.indiandentalacademy.com
  • Visual treatment objective Step 9 obj. – To reposition lower incisor - Calculate resultant arch length change • Arch length change - measure the distance b/w • old and new incisor position (2mm) Double the above distance • Arch length change is in this case is 4 mm www.indiandentalacademy.com
  • Visual treatment objective Step 10 obj. –To reposition mandibular first molar • Total arch length discrepancy = arch length loss +arch length discrepancy / model discrepancy 8 mm = 4 mm + 4mm • Extraction of 2nd PM on both side - 15 mm space Step 11 obj. – To reposition the maxillary first www.indiandentalacademy.com
  • Visualized treatment objective • • • Jacobson and Sadowsky Holdways Ricketts www.indiandentalacademy.com
  • A Soft - tissue cephalometric analysis Reed A. Holdway • Based on soft - tissue measurement Variations • Sella nasion line is used express forward growth • at nasion Growth on facial axis is 3mm/yr except during growth spurts www.indiandentalacademy.com
  • A Soft - tissue cephalometric analysis • Head films should be taken with the pt’s lip touching position www.indiandentalacademy.com
  • A Soft - tissue cephalometric analysis • • • • • • • • Original tracing – 9 reference line SN plane FH plane Occlusal plane Nasion to Pog line (hard & soft tissue) H- line Nasion to point A line / facial plane Facial axis Down’s Mandibular plane www.indiandentalacademy.com
  • A Soft - tissue cephalometric analysis Steps of VTO tracing Step 1 – Draw Frontonasal area Sella – nasion line Nasion- point A line www.indiandentalacademy.com
  • A Soft - tissue cephalometric analysis • • Step 2 - Express horizontal growth in the FN area for the estimated T/t Growth at nasion is 0.66 to 0.75 mm/yr Prediction of growth at nasion is an overall prediction for all midfacial structure www.indiandentalacademy.com
  • A Soft - tissue cephalometric analysis Step 3 – Mandible growth in vertical dire. • Growth on facial axis is 3 mm/yr except in growth spurt period Step 4 – Mandible growth in horizontal dire. • At this point total vertical height has been forecast www.indiandentalacademy.com
  • A Soft - tissue cephalometric analysis Step 5 – To locate maxilla, the new point A & lower half of nose • • Vertical growth above the SN line & below the mandible is in ratio of 40 :60 The vertical growth of the nose over 2 yr period keeps pace with the growth from the maxilla vertically to the anterior cranial base www.indiandentalacademy.com
  • A Soft - tissue cephalometric analysis Step 6 - locate and draw the occlusal plane • Vertical growth is 50% above maxilla & 50% • below mandible The occlusal plane is located 3 mm below the lip embrasure www.indiandentalacademy.com
  • A Soft - tissue cephalometric analysis Step 7 – To determine soft tissue lip contour using the new H-line • The distance b/w upper lip contour & H-line is • • 3 - 7mm Short & thin lip – 3 mm Long & thick lip – 5 mm www.indiandentalacademy.com
  • A Soft - tissue cephalometric analysis Step 8 – To relocate the maxillary central incisor • Upper lip thickness = Basic upper lip thickness • • ( within 1 mm ) Lip strain is difference b/w above measurement Maxillary incisor rebound - 0.5mm in class I - 1.5 mm in class II www.indiandentalacademy.com
  • A Soft - tissue cephalometric analysis Step 9 – To reposition lower incisor - Calculate resultant arch length change • Arch length change - distance b/w old and new • incisor position Double the above distance • Arch length change is in this case is 8 mm www.indiandentalacademy.com
  • A Soft - tissue cephalometric analysis Step 10 – To reposition mandibular first molar • Total arch length discrepancy = arch length change • +arch length discrepancy / model discrepancy 10 mm = 8mm + 2mm Extraction of 2nd PM on both side - 15 mm space Step 11 – To reposition the maxillary first www.indiandentalacademy.com
  • Visualized treatment objective • • • Jacobson and Sadowsky Holdways Ricketts www.indiandentalacademy.com
  • Visualized treatment objective • • • • • • • • • Original tracing RICKETTS Nasion ANS Point A PM POG CC Basion DC XI www.indiandentalacademy.com
  • Visualized treatment objective • • • • • • Construction of VTO Cranial base prediction Mandibular growth prediction Maxillary growth prediction Occlusal plane prediction The location of the dentition The soft tissue of the face www.indiandentalacademy.com
  • Visualized treatment objective VTO – Cranial base prediction • • • • Mark at CC point Trace BaN Plane Nasion -1mm /yr Basion – 1 mm/yr www.indiandentalacademy.com
  • Visualized treatment objective VTO –Mandibular growth prediction • Condylar axis growth • Corpus axis growth • Symphysis growth www.indiandentalacademy.com
  • Visualized treatment objective VTO – Mandibular growth prediction – Rotation • Mandible rotates open or closed from the effects of mechanics used & the facial pattern present • Mechanics 5 mm convexity reduction Facial axis open 1 degree 4 mm overbite correction • Facial pattern www.indiandentalacademy.com
  • Visualized treatment objective VTO – Mandibular growth prediction – Rotation • Superimpose at Basion • Rotate VTO tracing up to open the bite at nasion or • • down to open the bite This rotation depends on treatment effect Trace condylar axis, coronoid & condylar process www.indiandentalacademy.com
  • Visualized treatment objective VTO – Mandibular growth prediction Condylar axis , Corpus axis growth • Condylar axis moves 1mm /yr down from DC point • PM moves forward 2mm /yr in normal growth • • • VTO – Mandibular growth prediction -Symphysis growth Coincide old & new PM Copy the symphysis , mandibular plane www.indiandentalacademy.com Construct facial plane & facial axis
  • Visualized treatment objective • • • VTO – Maxillary growth prediction Superimpose at nasion along the facial plane Divide the original & new menton into 3 part by using 2 mark Superimpose mark 1 on original menton , copy the maxilla www.indiandentalacademy.com
  • Visualized treatment objective VTO – Maxillary growth prediction Point A change related to BA – NA • Position of Point A change with growth & different mechanics Mechanics Maximum range 1. HG - 8 mm 2. Class II elastics - 3 mm 3. Torque - 1 to 2 mm 4. Class III elastics + 2-3mm 5. Facial mask + 2- 4mm • Point A and APO plane www.indiandentalacademy.com
  • Visualized treatment objective VTO – Occlusal plane prediction • Superimpose mark 2 on original menton along facial • plane Copy the occlusal plane VTO - Dentition - Lower central incisor • • Superimpose on the corpus axis at PM Place a point 1mm above to occ. Plane & 1mm ahead to APO line www.indiandentalacademy.com
  • Visualized treatment objective VTO - Dentition - • • Lower first molar Arch length change is 4mm Leeway space is 4mm VTO - Dentition - Upper first molar Upper central incisor VTO – Soft tissue area www.indiandentalacademy.com
  • Growth prediction • Overall changes in size and relationship of human face from childhood to adulthood are difficult to accurately predict due to influence of the combined and complex effects of genetic and environment factor. www.indiandentalacademy.com
  • Growth prediction • Facial and dental changes in Adolescent and their clinical • • • • • implication Samir –E Bishara ,AO 2000,Vol.60,No.6 Difference between functional matrices in anterior open bite and in deep bite Melvin L. Moss, AJO 1970, Vol. 42,No.3 A principal of Arcial growth of the mandible Robert M . Ricketts AJO 1972,Vol .42 ,No.4 Provocations & perception in craniofacial orthopedics Robert M . Ricketts Issues related to the prediction of craniofacial growth James Todd , AJO 1981,Vol .79 ,No. 2 A soft tissue cephalometric analysis and it’s use in orthodontic treatment planning Holdway , AJO www.indiandentalacademy.com 4 1984 ,Vol. 84 ,No.
  • Growth prediction • A Visulized treatment objective • • • • • • Alen Jacobson , P Lionel Sadowsky Prediction of the mandibular growth rotation Bjork , AJO 1969 , Vol. 39 Bioprogessive Therapy – VTO Ruel W Bench , James J. Higler , JCO 1977, November Contemporary orthodontics - William R. Proffit Orthodontic current principles & techniques T.M Graber , Robert Vanarsdall Orthodontic principles & practice T.M Graber Ricketts interview ,JCO 1975 ,may, jun ,july www.indiandentalacademy.com
  • Thank you • www.indiandentalacademy.com • Leader in continuing dental education www.indiandentalacademy.com