CEPHALOMETRIC
ANALYSIS

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Leader in continuing dental education
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WITS APPRAISAL
• Since the introduction of ANB angle,it has been
one of the most popular means of cephalometric
evaluation...
• Relating the jaws to SN plane has certain
inherent inconsistencies because of
possible variations in the craniofacial
ph...
Effect of position of Nasion
A) Normal relationship
B) Nasion forward due
to long cranial base.
C) Nasion
retropositioned ...
Effect of angulation of jaws,
occlusal plane on ANB angle
A) Normal relationship.
B) Effect of
counterclockwise
rotation o...
•

Recognizing these shortcomings of ANB angle,
number of authors came up with alternative method-

1)

Jenkins (1955)-use...
• ‘WITS’- abbreviation for university of
witswatersrand,Johannesburg,South Africa.
• According to Jacobson- It is not an a...
• Occlusal plane is
drawn through the
region of overlapping
cusps of premolars &
molars.
• Perpendiculars are
drawn on occ...
• In a sample of 21 adult males selected on basis of
excellence of occlusion, it was found that BO was
approx. 1mm ahead o...
Applications of wits appraisal
•

The ANB angle is shown to be affected by several enviornmental
factors,diagnosis based o...
•
•

6) Mandibular plane angle –
High angle suggests a
divergent type profile,
clockwise rotation of jaws,
resultant incre...
• DRAWBACKS – Largely dependent on correct location
or representation of the occlusal plane. Sometimes right
& left sides ...
• As growth takes place,there is change in
position of B point,which is masked by
increasing prominence of the chin.
• The...
SASSOUNI’S ANALYSIS
• First published in AJO 1955,won first prize in
Essay contest sponsored by American
Association of Or...
• Problem – How can we study the architecture ?
• What is the significance of this architecture for diagnosis
and treatmen...
Terminology

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Planes
1
Mandibular
plane,OG –
Tangent to inferior
border.
2 Occlusal plane,OPTh...
• 4 Anterior cranial
base plane
angle,OS’- parallel to
axis of upper contour
of anterior cranial
base & tangent to
inferio...
•

ARCS-

•

1 Anterior arc – Between
anterior cranial base plane
& mandibular plane,with O
as center & O – ANS as
radius....
• Analysis- Mandible, Palate and Anterior cranial base are
examined.
• Mandible – 3 types
• 1 Curved – Upward traction for...
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Palate
• Horizontal – Line
connecting ANS-PNS
passes through bony
structure of the palate.
• Convex – Line passes
above th...
• Relationship –
• With curved
mandible; horizontal
palate.
• Oblique mandible;
convex palate.
• Horizontal mandible;
conc...
Key Ridge
• Presents 2 shapes –
Vertical & straight ,or Ilike.
• Double curved,like a
reverse 3 or like a sigma.
• Relatio...
Relationship between mandibular plane,occlusal
plane,palatal plane & anterior cranial base plane
• In a well proportioned
...
Posterior relationship in a well–proportioned face
•

•

If we draw a circle with O as
center,passing through
posterior wa...
Relationship between anterior & posterior arcs
•
•
•
•
•
•
•
•

Face is delimited by –
Above by anterior cranial base
plan...
Relationships between angles
• Angle S’OG (Mandibular
cranial angle) is unique to
each individual face.
• Angle S’ON
(Pala...
Classification of facial types
• I – Anterior cranial base
plane does not meet
three other planes at
common point O.
• II ...
• In the sample studied ,type II facial pattern
was most frequent.
• Normal occlusion is condition necessary
but not suffi...
Classification based on vertical Proportions
• I Equal – Upper &
lower faces are equal.
Cranial base plane ANS = ANS – M.P...
Classification of profile
• I Archial – Anterior
arc passes through
Na,ANS,upper incisor
edge,pogonion.

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• II Pre archial –
ANS,Upper
incisor,Pogonion are
situated anterior to
anterior arc passing
through Na.

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• III Post archial –
Situated posterior to
anterior arc.

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• Convex – ANS,Upper
incisor , are situated
anterior to anterior arc
passing by
Na,Pogonion.

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• Concave – ANS &
upper incisor are
situated posterior to
anterior arc passing
by Na & pogonion.

www.indiandentalacademy....
Conclusions
• A complete well proportioned face as seen on
lateral X ray film is one in which –
• 1) Four facial planes me...
• Thus there can be number of well
proportioned faces as it is a question of
proportion & not of absolute size.
• Acc. To ...
The Sassouni cephalometric analysis – A Racial
Comparison.
Dr. Ashima Valiathan J.I.D.A.1977
•

Compared the caucasians,Ne...
JARABAK ANALYSIS
• Presented by Joseph R .Jarabak in 1972.
• Composite analysis, takes into account
the skeletal aspects o...
• Takes into account ,the relationship
between anterior & posterior cranial base,
face & cranium, cranium & mandible.
• In...
• A feature of analysis is POLYGON, Na – S – Ar –
Go - Me to assess
anterior & posterior face
height relationships & to
pr...
• At age 11, anterior cranial base ( S-Na) should
equal to mandibular body length ( Go-Me).
• Ideal ratio of posterior cra...
www.indiandentalacademy.com
• COUNTERCLOCKWISE CHANGE –
• 3 angles sum is < 396°,ratio of posterior to
anterior face height 65 to 80 %.
• More rapidly...
• Sample –
• Origin – some of the measurments were
described & taken . Bjork cephalometric
analysis.
• Facial growth predi...
MEASUREMENTS
• Saddle angle – Cranial
base bend formed by
joining N-S-Ar. Mean
Value – 123 ± 5°.
• Among Indians mean
valu...
• Large angle – Mandibular fossa growth will be
more posterior for the remaining growth
increment. Leads to increase in le...
• Flexure in saddle angle can be either large
or small in 3 body types.
• Higher angle – ectomorphs,
• lower angles – endo...
• Articular angle – is
between S-Ar-Go.
• Mean value – 143 ±
6°.
• Indian – 141 ± 2°.
• Can be changed by
orthodontic trea...
• If bite is closed by moving posterior teeth
anteriorly,articular angle will decrease.
• Females have a slightly higher a...
•
•
•
•

Gonial angle- between Ar-Go-Gn.
Expresses the form of mandible & its growth
direction.
Mean value – 128 ± 7°
Indi...
• To determine the angular
relationship in which the
ramus & mandibular body
are put together angle is
divided into 2 part...
• Upper angle – Slant of ramus .
• Mean value – 52° – 55°
• Indian value – 51° ,South Indian males show a higher
value.
•
...
• Thus on completion of treatment,an
allowance for growth must be made,
leaving a somewhat greater overjet.
• Provides inc...
Ramus height
• Distance between Go
& Ar.
• Mean value – 44 ±
5mm.
• Boys – 40 – 46mm.
• Girls – 38 – 40 mm.
• Indian value...
• In boys ramus height increases 1 – 2
mm /yr , in girls : ¾ to 1 ¼ mm/ yr.
• As long as 3: 4 ratio ( posterior cranial
le...
Mandibular body length
• From Go – Me.
• Mean value : 71± 5mm.
• Increase in mandibular body length contributes
little to ...
Posterior & Anterior facial height
• Ratio of posterior to
anterior face height of 56
– 62 % indicates
clockwise growing f...
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Facial depth & Facial length
• Facial depth –
distance from Na to
Go.
• Facial length –
distance from sella to
the interse...
• Facial depth increases with growth in
almost all faces.
• Increment is greater when both gonial
angles are small.
• Faci...
DENTURE ANALYSIS
• Mandibular incisors to
facial plane –
• Ideally : 2mm in front or
behind facial plane.
• if posterior t...
• Ideal relation of maxillary teeth to facial
plane is 5 ± 2 mm.
• In Indians, South Indian show greater
maxillary dental ...
Relating Mandibular molars to symphysis
• Linear measurement
of distance from
mandibular 1st molar
( crown or mesial
root)...
• If distance from these 2 points decreases
as a result of treatment , it indicates
molars were moved forward.
• Will resu...
SOFT TISSUE PROFILE

• Analysis uses Rickett’s E plane because
of its simplicity ,reliability & chair side use.
• Esthetic...
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• Nose being the most changeable of the 2
reference structures, has a profound
influence on relations of lips to the E
pla...
REFERENCES
• 1 Valiathan A : Sassouni’s Cephalometric
analysis – A racial comparison. J I D A 1977;
49 : 393 – 95.
• 2 Val...
• 5 Jacobson: Wits appraisal of jaw disharmony.
AJO 1975.
• 6 Sherman, Woods, Nanda: Longitudinal effects
of growth on wit...
Thank you
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Leader in continuing dental education

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Wits, sassouni, jarabak /certified fixed orthodontic courses by Indian dental academy

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Wits, sassouni, jarabak /certified fixed orthodontic courses by Indian dental academy

  1. 1. CEPHALOMETRIC ANALYSIS www.indiandentalacademy.com
  2. 2. INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com www.indiandentalacademy.com
  3. 3. WITS APPRAISAL • Since the introduction of ANB angle,it has been one of the most popular means of cephalometric evaluation of the A-P relationship of apical bases. • There are many situations in which ANB reading cannot be relied upon. • Purpose of Wits appraisal is to identify these instances where ANB reading does not accurately reflect the extent of A-P jaw dysplasia. www.indiandentalacademy.com
  4. 4. • Relating the jaws to SN plane has certain inherent inconsistencies because of possible variations in the craniofacial physiognomy ,such as• 1) The A-P position of nasion relative to jaws. • 2) The rotational effect of jaws relative to cranial reference plane. www.indiandentalacademy.com
  5. 5. Effect of position of Nasion A) Normal relationship B) Nasion forward due to long cranial base. C) Nasion retropositioned due to short cranial base. www.indiandentalacademy.com
  6. 6. Effect of angulation of jaws, occlusal plane on ANB angle A) Normal relationship. B) Effect of counterclockwise rotation of face . C) Effect of clockwise rotation of face. www.indiandentalacademy.com
  7. 7. • Recognizing these shortcomings of ANB angle, number of authors came up with alternative method- 1) Jenkins (1955)-used functional occlusal plane. 1) Harvold (1963)- Projected points A and B onto occlusal plane. Termed the resulting measurement as A-B difference. 2) Jacobson (1975)- Published the classic article, “The Wits appraisal of jaw disharmony” www.indiandentalacademy.com
  8. 8. • ‘WITS’- abbreviation for university of witswatersrand,Johannesburg,South Africa. • According to Jacobson- It is not an analysis per se;rather it is intended as a diagnostic aid whereby the severity or degree of A-P disharmony can be measured. • Measure of extent to which jaws are related to each other A-P, independent of relationship to cranial landmarks. www.indiandentalacademy.com
  9. 9. • Occlusal plane is drawn through the region of overlapping cusps of premolars & molars. • Perpendiculars are drawn on occlusal plane from points A & B. • Contact points labelled as AO & BO. www.indiandentalacademy.com
  10. 10. • In a sample of 21 adult males selected on basis of excellence of occlusion, it was found that BO was approx. 1mm ahead of AO. • In 25 adult females ,AO & BO coincided. • Therefore average jaw relationship according to wits reading is – -1mm in males 0mm in females Clinical Significance - In skeletal class II,BO located well behind AO. In skeletal class III,BO would be forward of point AO. Greater the wits reading – Greater the jaw discrepancy. www.indiandentalacademy.com
  11. 11. Applications of wits appraisal • The ANB angle is shown to be affected by several enviornmental factors,diagnosis based on this angle may give false results,in certain cases. • Factors affecting ANB angle- • 1) Patient’s age- ANB has a definite tendency to reduce with increasing age. • 2) Change in spatial position of nasion. • 3) Rotational effect of jaws • 4) Change in the angle SN to occlusal plane. • 5) The degree of facial prognathism. www.indiandentalacademy.com
  12. 12. • • 6) Mandibular plane angle – High angle suggests a divergent type profile, clockwise rotation of jaws, resultant increase in ANB reading. • In many cases where SNA, SNB angles are in no way representative of jaw disharmony, wits appraisal may be conveniently applied. www.indiandentalacademy.com
  13. 13. • DRAWBACKS – Largely dependent on correct location or representation of the occlusal plane. Sometimes right & left sides of posterior teeth don’t always coincide. • In mixed dentition with deep bite,constructed occlusal plane may differ considerably from functional occlusal plane of deciduous & permanent molars • If curve of spee is deep,it may be difficult to follow the plane of maximum intercuspation. • The angulation of functional occlusal plane to pterygomaxillary vertical plane has been shown to decrease from age 4 to 24. • ( Sherman,Woods,Nanda, AJO-DO,May 1988) www.indiandentalacademy.com
  14. 14. • As growth takes place,there is change in position of B point,which is masked by increasing prominence of the chin. • The ‘wits’ appraisal is intended not as a single diagnostic criteria but as an additional measurement, which may be included in the existing cephalometric analysis to aid in the assessment of the degree of A-P jaw disharmony . www.indiandentalacademy.com
  15. 15. SASSOUNI’S ANALYSIS • First published in AJO 1955,won first prize in Essay contest sponsored by American Association of Orthodontics. • According to sassouni- “Architecture of skull is result of many forces ,genetic forces,growth forces,muscular,functional,enviornmental forces on the adaptable bony substance.” • At each period of life the skull is the end result of the interaction of these forces. www.indiandentalacademy.com
  16. 16. • Problem – How can we study the architecture ? • What is the significance of this architecture for diagnosis and treatment? • Are disturbances or disproportions in facial architecture possible etiological factors in orthodontics, oral surgery, prosthetics & periodontics ? • Aim – To find some acceptably constant relationships in the architecture of the head & to use them for diagnosis & treatment. • Material – 100 lateral head X-ray films (51 girls,49 boys). White children of Mediterranean racial origin. www.indiandentalacademy.com
  17. 17. Terminology www.indiandentalacademy.com Planes 1 Mandibular plane,OG – Tangent to inferior border. 2 Occlusal plane,OPThrough mesial cusps of permanent 1st molars & incisal edges of incisors. 3 Palatal plane,ON – perpendicular to mid sagittal plane,through ANS-PNS.
  18. 18. • 4 Anterior cranial base plane angle,OS’- parallel to axis of upper contour of anterior cranial base & tangent to inferior border of sella turcica • 5 Ramal plane – Tangent to posterior border of ascending ramus. www.indiandentalacademy.com
  19. 19. • ARCS- • 1 Anterior arc – Between anterior cranial base plane & mandibular plane,with O as center & O – ANS as radius. • 2 Posterior arc – Between anterior cranial base plane & mandibular base plane,O centre, OSp as radius. ( Sp is most posterior point on rear margin of sella turcica ) www.indiandentalacademy.com
  20. 20. • Analysis- Mandible, Palate and Anterior cranial base are examined. • Mandible – 3 types • 1 Curved – Upward traction forces at gonion & downward pulling force at the menton are in equilibrium. • 2 Oblique – Upward traction & downward pulling forces seem to be so strong that we have a notch just anterior to the gonial insertion of masseter. • 3 Horizontal - Upward traction forces at gonion seems to be greater than downward pulling forces at menton. www.indiandentalacademy.com
  21. 21. www.indiandentalacademy.com
  22. 22. Palate • Horizontal – Line connecting ANS-PNS passes through bony structure of the palate. • Convex – Line passes above the bony structure of palate. • Concave – Line passes below the bony structure of palate. www.indiandentalacademy.com
  23. 23. • Relationship – • With curved mandible; horizontal palate. • Oblique mandible; convex palate. • Horizontal mandible; concave palate www.indiandentalacademy.com
  24. 24. Key Ridge • Presents 2 shapes – Vertical & straight ,or Ilike. • Double curved,like a reverse 3 or like a sigma. • Relation- When palate is concave or convex,key ridge is sigma like. • When palate is horizontal;key ridge is I – like. www.indiandentalacademy.com
  25. 25. Relationship between mandibular plane,occlusal plane,palatal plane & anterior cranial base plane • In a well proportioned face, all meet posteriorly at the same point O. • If we draw a circle from O as a center,with O-ANS as radius,it passes through – pogonion,nasion,ANS, incisal edge of upper incisor. • All these points are equidistant from O. www.indiandentalacademy.com
  26. 26. Posterior relationship in a well–proportioned face • • If we draw a circle with O as center,passing through posterior wall of sella turcica (Sp),it also passes through gonion. It can be said that – • A) Gonion & posterior wall of sella turcica are equidistant from O. • B) Anterior cranial base & corpal length of mandible are equal in length & position. www.indiandentalacademy.com
  27. 27. Relationship between anterior & posterior arcs • • • • • • • • Face is delimited by – Above by anterior cranial base plane,OS’. Below by mandibular plane ,OG. Anteriorly by arc passing through ANS. Posteriorly by arc passing through Sp Proportion between anterior & posterior arcs is a function of angle S’O G , ratio of both radii Ra (O-ANS) / Rp (O-SP). Combination of S’OG and Ra/Rp is facial index. www.indiandentalacademy.com
  28. 28. Relationships between angles • Angle S’OG (Mandibular cranial angle) is unique to each individual face. • Angle S’ON (Palatocranial ) = Angle NOG (Palatomandibular) • Angle NOP (Occlusopalatal ) is between 1/1 & 1/2 Angle POG (occlusomandibular) • Angle POG is always larger than angle NOP in a well proportioned face. www.indiandentalacademy.com
  29. 29. Classification of facial types • I – Anterior cranial base plane does not meet three other planes at common point O. • II – Palatal plane does not meet at O. • III – Occlusal plane does not meet at O. • IV – Mandibular plane does not meet at O. • Type A – Plane passes above point O. • Type B – Below point O. www.indiandentalacademy.com
  30. 30. • In the sample studied ,type II facial pattern was most frequent. • Normal occlusion is condition necessary but not sufficient for a well proportioned face. • Among 50 cases with normal occlusion,only 16 had well proportioned faces. www.indiandentalacademy.com
  31. 31. Classification based on vertical Proportions • I Equal – Upper & lower faces are equal. Cranial base plane ANS = ANS – M.P. II Minus – Lower face is smaller than upper face. III Plus – Lower face is larger. www.indiandentalacademy.com
  32. 32. Classification of profile • I Archial – Anterior arc passes through Na,ANS,upper incisor edge,pogonion. www.indiandentalacademy.com
  33. 33. • II Pre archial – ANS,Upper incisor,Pogonion are situated anterior to anterior arc passing through Na. www.indiandentalacademy.com
  34. 34. • III Post archial – Situated posterior to anterior arc. www.indiandentalacademy.com
  35. 35. • Convex – ANS,Upper incisor , are situated anterior to anterior arc passing by Na,Pogonion. www.indiandentalacademy.com
  36. 36. • Concave – ANS & upper incisor are situated posterior to anterior arc passing by Na & pogonion. www.indiandentalacademy.com
  37. 37. Conclusions • A complete well proportioned face as seen on lateral X ray film is one in which – • 1) Four facial planes meet at point O. • 2) Anterior upper & lower faces are equal. • 3) Posterior upper & lower faces are equal. • 4) Profile is archial. • 5) Corpus of mandible is equal in size & position to the anterior cranial base. www.indiandentalacademy.com
  38. 38. • Thus there can be number of well proportioned faces as it is a question of proportion & not of absolute size. • Acc. To Sassouni : “We have to admit that there is no universal normality; there is no norm which can be applied indiscriminately to every body” www.indiandentalacademy.com
  39. 39. The Sassouni cephalometric analysis – A Racial Comparison. Dr. Ashima Valiathan J.I.D.A.1977 • Compared the caucasians,Negro,Indian profiles. Findings – • 1) Majority of caucasians have archial profile, majority of Indians have post archial ( 65%) ,largest number of negroes presented with a post-archial profile. • 2) Both Indians & Negroes showed an overall procumbency of the anterior teeth. • 3) Compared to caucasians who showed equal upper & lower facial heights,in Indians the anterior & posterior lower facial height were more. • 4) Corpus of mandible was found to be longer than the cranial base in Indians as well as Negroes. www.indiandentalacademy.com
  40. 40. JARABAK ANALYSIS • Presented by Joseph R .Jarabak in 1972. • Composite analysis, takes into account the skeletal aspects of growth as described by Bjork. • Analysis can be used in clinical assessment of growth events to follow, shows how to design treatment in anticipation of these growth events. www.indiandentalacademy.com
  41. 41. • Takes into account ,the relationship between anterior & posterior cranial base, face & cranium, cranium & mandible. • Interpret how craniofacial growth will influence the dentition during treatment or post treatment growth period. . www.indiandentalacademy.com
  42. 42. • A feature of analysis is POLYGON, Na – S – Ar – Go - Me to assess anterior & posterior face height relationships & to predict the direction of growth changes in lower face. • Basis of approach is relationship of 3 angles• 1 Saddle angle- Na-S-Ar • 2 Articular angle- S-Ar-Go • 3 Gonial angle- Ar-Go-Me www.indiandentalacademy.com
  43. 43. • At age 11, anterior cranial base ( S-Na) should equal to mandibular body length ( Go-Me). • Ideal ratio of posterior cranial base length ( S-Ar) to ramus height ( Ar-Go) is 3:4. • CLOCKWISE GROWTH CHANGE – If sum of 3 angles is > 396°, ratio of posterior ( S-Go) to anterior face height ( N-Me) is 56% to 64%. • Anterior face height is increasing rapidly, downward & backward growth change at symphysis, & anterior open bite tendency. www.indiandentalacademy.com
  44. 44. www.indiandentalacademy.com
  45. 45. • COUNTERCLOCKWISE CHANGE – • 3 angles sum is < 396°,ratio of posterior to anterior face height 65 to 80 %. • More rapidly increasing posterior face height, forward growth of condyle,anterior deep bite tendency. www.indiandentalacademy.com
  46. 46. • Sample – • Origin – some of the measurments were described & taken . Bjork cephalometric analysis. • Facial growth predictions were made after the age of 10 yrs, using the mean values based on 200 treated cases, 5 yrs after treatment. www.indiandentalacademy.com
  47. 47. MEASUREMENTS • Saddle angle – Cranial base bend formed by joining N-S-Ar. Mean Value – 123 ± 5°. • Among Indians mean value 124 ± 4°. North Indians have a higher saddle angle, indicate a slightly posterior position of mandible. • ( Manish Valiathan ,Ashima Valiathan, V.Ravinder, JIOS 2001). www.indiandentalacademy.com
  48. 48. • Large angle – Mandibular fossa growth will be more posterior for the remaining growth increment. Leads to increase in length of body of mandible , arrangement of ascending ramus if face has to remain orthognathic. • If mandibular body length is same or shorter than anterior cranial base, face will be retrognathic & continue to grow that way. • If angle is small,it tends to increase facial prognathism. • An extremely small angle can be seen in achondroplastic patients. www.indiandentalacademy.com
  49. 49. • Flexure in saddle angle can be either large or small in 3 body types. • Higher angle – ectomorphs, • lower angles – endomorphic & mesomorphic pattern. • Lokar showed in a stastically significant sample that a small saddle angle is one of the most frequently seen characteristics of skeletal class III malocclusions. • Saddle angle is in no way influenced by orthodontic treatment. www.indiandentalacademy.com
  50. 50. • Articular angle – is between S-Ar-Go. • Mean value – 143 ± 6°. • Indian – 141 ± 2°. • Can be changed by orthodontic treatment. • If bite is opened by extrusion of teeth or by driving molars distally, angle will increase. www.indiandentalacademy.com
  51. 51. • If bite is closed by moving posterior teeth anteriorly,articular angle will decrease. • Females have a slightly higher articular angle than males indicating that females have a retrognathic mandibles in comparison with males. www.indiandentalacademy.com
  52. 52. • • • • Gonial angle- between Ar-Go-Gn. Expresses the form of mandible & its growth direction. Mean value – 128 ± 7° Indian – 120 ± 1° Manner in which ascending ramus & mandibular body are related to each other to form gonial angle determines how the mandibular growth will influence facial structure. www.indiandentalacademy.com
  53. 53. • To determine the angular relationship in which the ramus & mandibular body are put together angle is divided into 2 parts – • upper & lower gonial angle by facial depth line through a tangent of lower border of mandible & posterior surface of ascending ramus. www.indiandentalacademy.com
  54. 54. • Upper angle – Slant of ramus . • Mean value – 52° – 55° • Indian value – 51° ,South Indian males show a higher value. • • • • Lower angle – Slant of body of mandible. Mean value – 70 ° – 75 ° Indian value - 69° If upper angle is large, remaining growth increment will be in sagittal direction. • If it is small, remaining increment will be downward or downward & backward. www.indiandentalacademy.com
  55. 55. • Thus on completion of treatment,an allowance for growth must be made, leaving a somewhat greater overjet. • Provides incisive freedom between anterior teeth. • Otherwise either mandibular crowding may follow or anterior teeth may begin to assume a class III relationship. www.indiandentalacademy.com
  56. 56. Ramus height • Distance between Go & Ar. • Mean value – 44 ± 5mm. • Boys – 40 – 46mm. • Girls – 38 – 40 mm. • Indian value; • Males : 51 – 54 mm • Females: 47mm. www.indiandentalacademy.com
  57. 57. • In boys ramus height increases 1 – 2 mm /yr , in girls : ¾ to 1 ¼ mm/ yr. • As long as 3: 4 ratio ( posterior cranial length to ramus height ) prevails children having small faces would show favorable downward mandibular growth. www.indiandentalacademy.com
  58. 58. Mandibular body length • From Go – Me. • Mean value : 71± 5mm. • Increase in mandibular body length contributes little to total facial prognathism, tend to increase mandibular prognathism. • A good incisor relation van go into class III, open bite as a result of increase in ramus & mandibular body length. • Usually happens when – saddle angle is small, mandibular body length to cranial base length is > than 1.1 : 1: ; ramus height is more than 46mm & upper gonial angle is large. www.indiandentalacademy.com
  59. 59. Posterior & Anterior facial height • Ratio of posterior to anterior face height of 56 – 62 % indicates clockwise growing face. • 65 – 82 % - higher posterior facial growth takes place, face grew counter – clockwise. • If posterior face is short , one can expect face to be more retrognathic. www.indiandentalacademy.com
  60. 60. www.indiandentalacademy.com
  61. 61. Facial depth & Facial length • Facial depth – distance from Na to Go. • Facial length – distance from sella to the intersecting lines of facial & mandibular planes www.indiandentalacademy.com
  62. 62. • Facial depth increases with growth in almost all faces. • Increment is greater when both gonial angles are small. • Facial length is a function of horizontal & vertical growth combined, will be greater where growth increments of lower face are more horizontal than vertical. www.indiandentalacademy.com
  63. 63. DENTURE ANALYSIS • Mandibular incisors to facial plane – • Ideally : 2mm in front or behind facial plane. • if posterior to plane,chin are prominent, & lips are withdrawn. ( Dished in). • Anterior to facial plane : lower face has a denture prominence. www.indiandentalacademy.com
  64. 64. • Ideal relation of maxillary teeth to facial plane is 5 ± 2 mm. • In Indians, South Indian show greater maxillary dental protrusion; South Indian females have greater mandibular dental protrusion. • Maxillary incisor to SN plane – Mean angulation : 102 ± 2°. www.indiandentalacademy.com
  65. 65. Relating Mandibular molars to symphysis • Linear measurement of distance from mandibular 1st molar ( crown or mesial root) to posterior border of symphysis. • Indirectly tells abount the degree of overbite that may develop in retention & post retention periods. www.indiandentalacademy.com
  66. 66. • If distance from these 2 points decreases as a result of treatment , it indicates molars were moved forward. • Will result in increased overbite after teeth have settled in function • If roots & crowns moved in different amounts , means molar were tipped during treatment. www.indiandentalacademy.com
  67. 67. SOFT TISSUE PROFILE • Analysis uses Rickett’s E plane because of its simplicity ,reliability & chair side use. • Esthetic E line : straight line from tip of nose to tip of chin. • Desirable relation : Lower lip lightly touches the straight edge & upper lip is 2 – 4 mm behind E line. www.indiandentalacademy.com
  68. 68. www.indiandentalacademy.com
  69. 69. www.indiandentalacademy.com
  70. 70. www.indiandentalacademy.com
  71. 71. • Nose being the most changeable of the 2 reference structures, has a profound influence on relations of lips to the E plane. • Influence is not seen before 14 th yr. • From 14 – 18 yrs it grows considerably in boys. • Generally prominent in malocclusions characterized by forward maxilla. www.indiandentalacademy.com
  72. 72. REFERENCES • 1 Valiathan A : Sassouni’s Cephalometric analysis – A racial comparison. J I D A 1977; 49 : 393 – 95. • 2 Valiathan M, Valiathan A, V.Ravinder: Jarabak analysis reborn. J I O S 2001;34 : 66 -76. • 3 Jarabak, Fizzell: Technique and treatment with light wire edgewise appliance.St. Louis, Mosby , 2nd edtn,Vol I ; Pg- 131 – 166. • 4 Sassouni V. : A roentgenographic cephalometric analysis of cephalo-facial dental relationships. AJO 1955; 735 -61. www.indiandentalacademy.com
  73. 73. • 5 Jacobson: Wits appraisal of jaw disharmony. AJO 1975. • 6 Sherman, Woods, Nanda: Longitudinal effects of growth on wits appraisal. AJO 1988. • 7 Samir E. Bishara, Julie A. Fahl, Larry C. Peterson: Longitudinal changes in ANB angle and wits appraisal – Clinical implications. AJO 1983;84 (2): 133 -39 • 8 Jacobson : Introduction to radiographic cephalometry. Lea & Febgier, Philadelphia; 1985,2nd edtn. Pg-63 – 71. www.indiandentalacademy.com
  74. 74. Thank you www.indiandentalacademy.com Leader in continuing dental education www.indiandentalacademy.com

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