for lecture of Undergraduates

1. Contents
 Introduction
 Steiner’s Analysis
 Down’s Analysis
 Tweed’s Analysis
 Wits Apprasial
 Ricketts Analysis
 McNamara Analysis
 Di paolo Quadilateral Analysis
 Holdaway’s Analysis
 Jarabak Analysis
 Arnett Analysis
 Bibliography

2. Introduction :-
 The assessment of craniofacial dimensions is not a new
skill in orthodontics. The earliest method was used to
assess facial proportions from the artistic point of view.
During the Renaissance, Durer analysed the human
face, determined the ideal proportions & divide the face
into four quadrants .
 Many centuries later, his method was applied to the
analysis of cephalometric radiographs by de Coster &
Moorees. Cephalometry (scientific measurement of the
dimensions of the head ) was the first method to prove
of value in orthodontics

3.  The first X-ray picture of the skull in the standard lateral
view were taken by Pacini & Carrera (1922). In the
subsequent years, the various authors also produced the
following type of radiographs for craniofacial
measurements: MacGowen(1923), Simpson(1923),
Comte(1927), Riesner(1929), & others. But none of them
have given the accurate description of the method to
take pictures.
 In 1931, Hofrath & Broadbent simultaneously &
independently developed standarized method for the
production of cephalometric radiographs, using special
holders known as cephalostats.

4.  This technique was developed in 1930s but gained wider
acceptance for practical use during the last 3-4 decades
 The aims of the assessment tended to vary, ranging
from studies on the facial growth, the location of
malformations, aetiological studies to the assesment of
treatment response, as a complement to status analysis
in orthodontics.
 For clinical application, the methods designed to assist
diagnosis are of particular interest. The many different
diagnostic analysis may be differentiated in a number of
ways.

5. RADIOGRAPHIC CEPHALOMETRIC
TECHNIQUE
 The basic components of the equipment
for producing a lateral cephalometric are:
 1. An X-ray apparatus
 2. An image receptor system
 3. A cephalostat.

6. X-ray Apparatus:-
comprises of X-rays tube, transformers, filters, collimators,
and a coolant system, all encased in the machine’s
housing.
 The three basic elements that generate the X- rays
a. a cathode
b. an anode
c. the electrical power supply
a. Cathode:-
is a tungsten filament surrounded by a
molybdenum. And serves as a source of electrons.

8. b. An anode :-
 It consist of a tungsten target embedded in a copper
stem. The purpose of the target in an x ray tube is to
convert the kinetic energy of the electrons generated
from the filament in to x ray photons. Less than 1 % of
the electron kinetic energy is converted to the x rays
photons.
 The size of the focal spot , which determines image
quality. The target face in the x ray tube is oriented at an
angle of 15 to 200 to the cathode .
 The size or area of the effective focal spot created by the
inclined target is between 1x1 mm2 and 1x2 mm2 .

9.  the low- energy photons are filtered out by means of an
aluminium filter
 The divergent x ray beam then passes through a lead
diaphragm that fits over the opening of the machine
housing and determine the beam’s size and shape.
 Only x ray with sufficient penetrating power are allowed
to reach the patient
c. the electric power supply :-
the primary function of the power supply of an x ray
machine are to
1. provide a low voltage current to heat the x ray tube
filament by use of an step- down transformer
2. generate a high potential diff. between the anode
and cathode by use of a high- voltage transformer

10.  Image Receptor system ; Extra oral projection
like lateral ceph. requires a complex image
receptor system that consists of an extra oral
film, intensifying screens, a cassette, a grid and
soft tissue shield.
 Extra oral film is a screen film size ranging from
8x10 inches to 10x12 inches. Basic component
of the film are an emulsion of silver halide
crystals suspected in a gelatin frame work and a
transparent blue- tinted cellulose acetate that
serves as a base.

11. Cephalostat:- As described by Broadbent (1931).
 Patient’s head is fixed by 2 ear rods that are
inserted into the ear holes so that the upper
border of the ear holes rest on the upper part of
the ear rods.
 Head is centered in the cephalostat, is oriented
with the FHP parallel to floor and MSP vertical
and parallel to the cassette.
 Standardized FHP is achieved by placing the
infraorbital pointer at the patient’s orbit and then
adjusting the head until the infra-orbital pointer
and ear rods are at the same level.
 The upper part of face is supported by forehead
clamp positioned at nasion.

12.  The conventional use of 2 ear rods to stabilize the
head in radiograph. Cephalometry is based on the
assumption that the transmeatal axis of human is
perpendicular to mid-sagittal plane.
 Actually, asymmetry is a general characteristic and the
relationship of the left and right ears in their vertical and
horizontal relation to each other which is frequently
asymmetric.
 In these instances the insertion of ear-rods will
obviously result in vertical and/or horizontal rotation of
the head, which introduces a deficient and misleading
image. So only the left ear-rods should be used in
radiographic Cephalometry both for lateral and particular
for the frontal projection.

15. Down’s Analysis
 It was given by William B Down in 1948 at the
university of Illinois.
 Sample size :- 20 living individuals, ranging in age
from 12-17 yrs & equally divided as to sex, & of
Caucasian race.
 The Down’s analysis is divided into two parts:-
1. Skeletal pattern
2. Dental pattern

16. Skeletal pattern
 This include :-
1. Facial angle
2. Angle of convexity
3. A-B plane
4. Mandibular plane angle
5. Y axis

17. 87.80
Facial Angle :-
N
F H Plane
Pog

18. Angle of Convexity :-
N
A
Pog

19. -4.60
A-B Plane Angle:-
N
A
B
Pog
Facial
Plane

20. 21.90
Mandibular Plane Angle:-
F H Plane
O
P
Go
M

21. 59.40
Y-axis:-
F H Plane
S
Gn

22. Dental pattern
 It includes :-
1. Cant of occlusal plane
2. Interincisal angle
3. Incisor-occlusal plane angle
4. Incisor mandibular plane angle
5. Protrusion of maxillary incisor

23. 9.30
F H Plane
Cant of occlusal Plane:-

24. 135.40
Inter-incisal Angle

25. 14.50
Incisor occlusal plane angle:-

26. 1.40
Incisor mandibular plane angle:-

27. 2.7mm
Upper incisor to A-Pog:-
A
Pog

28. The Polygon
 It was developed by Vorhies & Adams in 1951 which is
also called as “wiggle” that represents the large group of
cephalometric readings graphically

30. Steiner Analysis
 In the year 1950s, Cecil C. Steiner developed this
analysis & is considered the first of the modern
cephalometric analyses for two reasons:
i) It displayed measurements in a way that emphasized
not just the individual measurements but there
interrelationship into a pattern .
ii) It offered specific guides for use of cephalometric
measurement in treatment planning
 The Steiner analysis is divided into three parts:-
1. Skeletal analysis
2. Dental analysis
3. Soft tissue analysis

31. Skeletal Analysis
1. S.N.A angle
2. S.N.B angle
3. A.N.B angle
4. Mandibular plane angle
5. Occlusal plane angle

32. 820
SNA Angle:-
N
S
A

33. 800
SNB Angle:- N
S
B

34. 20
ANB Angle:- N
A
B

35. 140
N
S
Occlusal plane:-

36. 320
Mandibular plane angle:-
S
N

37. Shortcomings of ANB

39.  Jenkins in 1955, elected
to use the functional
occlusal plane as a
reference base for the
measurement of the jaw
disharmony.
 He established the “a”
plane drawn through a
point A at right angle to
the occlusal plane, & then
measured from the “a”
plane to point B, gnathion,
& the mandibular incisor
edge.

40.  Betty in 1975, ANB angle is not always an accurate
method of establishing the actual amount of apical base
divergence.
 He devised the AXD angle for measuring the apical base
discrepancy, where point X is formed by projecting point
A onto a perpendicular to SN line, & point D is located in
the bony symphysis.

42. Dental Analysis
 This include:-
1. Upper incisor to N-A angle
2. Upper incisor to N-A linear
3. Lower incisor to N-B angle
4. Lower incisor to N-B linear
5. Inter Incisal angle

43. Upper incisor to N-A line:-
220
A
N

44. Upper incisor to N-A line:-
4 mm
N
A

45. Lower incisor to N-B line :-
250
N
B

46. Lower incisor to N-B line :-
4mm
N
B

47. Inter-incisal angle:-
1300

48. Soft tissue Analysis
 S-line:-
The lips in a well balanced faces, according to
Steiner ,should touch a line extending from the soft
tissue contour of the chin to the middle of an “S” formed
by the lower border of the nose. This line is referred to
as the S-line.

50. Steiner Stick
 It is also called as “chevrons”, a convenient
shorthand for presenting the measurement .
 He calculated that what compromises in incisor
positions would be necessary to achieve normal
occlusion when the ANB angle is not ideal. This
was a major step in applying cephalometric to
routine treatment planning.

51. Steiner stick

52. Ricketts Analysis
 It was given by Robert Murray Ricketts in 1961
 Purpose of analysis:-
 Characterize a particular type of condition
 Compare one individual to other
 Classify certain type of problems
 Communicate

53. Sample
 Size :-1000 consecutive patients
 Origin :-clinical cases with usual orthodontic race problems omitting
surgical class III, traumatic TMJ cases & operated cleft palate
patients
Class I – 399
Class II Div 1- 367
Class II Div 2- 217
Class III – 17
 Race :- white
 Sex :- 546 females ; 454 males of age group,
3-6 yrs – 61
7-10yrs – 497
11-14yrs- 343
15-18 yrs – 217
19-44 yrs – 33

54.  Location of Xi point:-
The location of the Xi point is keyed geometrically to
the Frankfort horizontal & the pterygoid root vertical
planes (PtV). The procedure follows :-
1. Locate FH plane & draw PtV plane perpendicular to
the FH plane
2. Construct four planes tangent to points R1, R2 ,R3 &
R4 on the border of the ramus

55.  R1-deepest point on the anterior border of the ramus
 R2-located on the posterior border of the ramus
 R3-deepest point on the sigmoid notch, halfway
between the superior & inferior curves
 R4-opposite R-3 on the inferior border of the mandible
3. The constructed plane form a rectangle enclosing the
ramus.
4. Xi point is located at the centre of the rectangle at the
intersection of the diagnosis.

57. Chin in Space
 This include :-
1. Facial axis
2. Facial (depth) angle
3. Mandibular plane

58. Facial axis :-
Ba
N
Gn

59. 870
Facial Depth :-
O
Po
Pog
N

60. 260
Mandibular plane angle:-

61. Convexity
 In this ;-
1. Convexity at point A
It is measured from point A to the facial plane .
The clinical norm at 9 yrs age is 2mm & decreases 10
every five yrs .high complexity implies a class II
skeletal pattern. Negative complexity suggests a class
III skeletal pattern .

62. N
Pog
A

63. Teeth
 This include :-
1. Lower incisor to A-Pog
2. Upper molar to PtV
3. Lower incisor inclination

64. 1mm
A
Pog
Lower incisor to A-Pog line:-

65. Upper molar to Ptv:-

66. 280
Lower incisor inclination:-
A
Pog

67. Profile
 Lower lip to E plane

68. Wits Appraisal
Sample :-
 Size- 46
 Race-Caucasian
 Sex 25 males;23 females
 Age – adults

69. AO
BO

70. Tweed’s Triangle
Sample :-
 Size - 95
 The objectives are :-
1. The best balance & harmony of facial lines
2. Stability of denture after treatment
3. Healthy mouth tissues
4. An efficient chewing mechanism

71. 250 650
900
F H Plane

72. McNamara Analysis
 It was given by McNamara JA in the year 1984.
 The composite normative standards used in the
McNamara were derived from 3 sourses:-
Lateral cephalograms of the children
comprising the Bolton standards
Selected values from a group of untreated
children from the Burlington Research Centre,
&
A sample of young adults from Ann Arobar
,Michigan, having good-to-excellent facial &
dental configuration

73.  Size – 111 young adults
 Race – caucasian
 Sex – male & female
 Age – average age of female is 26 yrs ; 8 months &
average age of male is 30 yrs; 9 months

74. Relating the maxilla to the cranial base
1020
Soft tissue Evaluation

75. Hard tissue Evaluation:-
F H Plane
N
A

76. Mandible to maxilla
 Effective length of maxilla (condyle to point A)
 Effective length of mandible (condyle to
gnathion)
 Maxillo-mandibular differential
 Lower anterior facial height (ANS to menton)
 Mandibular plane angle
 Facial axis

78. Facial axis:-
Ba
N
Ptm
Gn

79. Mandible to cranial base
F H Plane
N
Pog

80. Upper incisor to point A vertical

81. Lower incisor to A-Po line

82. Airway Analysis
 Upper pharynx:-the upper pharyngeal wall width is
measured from the posterior outline of the soft palate to
the closest point on the pharyngeal wall.
 Lower pharynx:-it is measured from the intersection
of the posterior border of the tongue & the inferior border
of the mandible to the closest point on the posterior
pharyngeal wall.

84. Di Paolo’s Quadilateral Analysis
 It was given by Di Paolo RJ in 1983.
 His sample size was 245 equal male and female, of 9-
15yr age group who had normal occlusion and were
untreated orthodontic patients.

85. Skeletal Assessment
 This includes :-
1. Maxillary length
2. Mandibular length
3. AUFH (anterior upper facial height)
4. ALFH (anterior lower facial height)
5. PLFH (posterior lower facial height)
6. Facial (angle of facial convexity)

88. Dental Assessment
 This include :-
1. Pogonion line:. This is constructed by drawing a line
tangent to pogonion and parallel to the anterior facial
height. The most anterior point of the mandibular
central incisor is then related perpendicular to the
pogonion line. The average is 2 mm. anterior or
posterior to the pogonion line. This measurement will
indicate whether the chin is excessive or deficient in
size.

89. 2. Point A line:-Maxillary incisor position is determined by
drawing a line through point A parallel to the anterior lower facial
height. A measurement is then made by drawing a perpendicular
from this line to the most anterior point on the maxillary central
incisor. The average measurement is 5 mm. plus or minus 1 mm.
3. Point B line :-Mandibular incisor position is determined by
drawing a line through point B. This line is parallel to the anterior
lower facial height. From this line, a measurement is made by
drawing a perpendicular from this line to the most anterior point
on the mandibular central incisor. The average measurement is 2
mm. plus or minus 1 mm.

91. Bibliography
 Radiographic cephalometry, Alexander jacobson pg no.
65-126, Quintessence publishing company
 Orthodontic cephalometry, Athanasios E Athanasiou pg
no. 241-282, Mosby-Wolfe.
 Cephalometric radiography, Thomas Rakosi pg no. 7,34-
46
 G William Arnett :Soft tissue cephalometric analysis Am
J Ortho 1999;116:239-53.

92.  Cecil C Steiner: Cephalometric for you & me Am J Ortho
1953 ;39 : 729-755
 Charles H Tweed: The Frankfort-Mandibular Incisor
Angle in Orthodontic Diagnosis, Treatment Planning &
Prognosis AO 1954; 3: 121-169
 Robert Murray Ricketts :Cephalometric Analysis &
Synthesis Am J Ortho 1961; 31 :141-156
 Rocco J Di Paolo :The quadrilateral analysis Am J Ortho
1984;86 :470-482
 A Jacobson The Wits apprasial of jaw disharmony :Am J
Ortho 1975;67 :125-138
 Reed A Holdaway A soft-tissue cephalometric analysis &
its use in orthodontic treatment planning Am J Ortho
1983;84:1-28