This document provides an overview of cephalometric analysis techniques including Steiner's analysis, Tweed's analysis, and Down's analysis. It discusses the skeletal, dental, and soft tissue measurements used in each analysis and provides the normal values. Common landmarks are defined along with the angles and linear measurements used to evaluate skeletal and dental relationships. Sources of error in cephalometry are addressed. The applicability of various analyses to different populations is also reviewed based on studies of cephalometric norms in Indian and other ethnic groups.

1. CEPHALOMETRY-2
DR KOMAL GHIYA
MDS PEDODONTICS AND
PREVENTIVE DENTISTRY
1

2. INDEX
CEPHALOMETRIC ANALYSIS
STEINER’S ANALYSIS
TWEED’S ANLAYSIS
DOWN’S ANALYSIS
ERRORS IN CEPHALOMETRY
RECENT ADVANCES
2

3. STEINER’S ANALYSIS
SKELETAL ANALYSIS:
SNA ANGLE:
INDICATES THE RELATIVE
ANTEROPOSTERIOR POSITIONING OF
MAXILLA IN RELATION TO THE CRANIAL
BASE
MEAN VALUE:82
3
WILLIAM R. PROFFIT, HENRY W. FIELDS JR., DAVID M.
SARVER,CONTEMORARY ORTHODONTICS, 2006

4. SNB ANGLE:
INDICATES THE ANTEROPOSTERIOR POSITIONING OF MANDIBLE IN
RELATION TO CRANIAL BASE
AVERAGE ANGLE:80
4
WILLIAM R. PROFFIT, HENRY W. FIELDS JR., DAVID M.
SARVER,CONTEMORARY ORTHODONTICS, 2006

5. ANB ANGLE:
RELATIVE POSITION OF MAXILLA AND MANDIBLE TO EACH OTHER
MEAN VALUE:2
5
WILLIAM R. PROFFIT, HENRY W. FIELDS JR., DAVID M.
SARVER,CONTEMORARY ORTHODONTICS, 2006

6. MANDIBULAR PLANE
ANGLE:AVERAGE VALUE :32
ANGLE INDICATES THE
GROWTH PATTERN OF AN
INDIVIDUAL
A LOWER ANGLE INDICATES
HORIZONTAL GROWING FACE
INCREASED ANGLE SUGGESTS
VERTICAL GROWING
INDIVIDUAL
6
WILLIAM R. PROFFIT, HENRY W. FIELDS JR., DAVID M.
SARVER,CONTEMORARY ORTHODONTICS, 2006

7. OCCLUSAL PLANE ANGLE:
MEAN VALUE:15.5
ANGLE INDICATES THE RELATION OF OCCLUSAL PLANE TO CRANIUM
AND FACE
INDICATES GROWTH PATTERN OF AN INDIVIDUAL
7
WILLIAM R. PROFFIT, HENRY W. FIELDS JR., DAVID M.
SARVER,CONTEMORARY ORTHODONTICS, 2006

8. DENTAL ANALYSIS
UPPER INCISOR TO N-A
(ANGLE): NORMAL ANGLE:22
INDICATES RELATIVE
INCLINATION OF UPPER
INCISOR
INCREASED ANGLE INDICATES
PROCLINED UPPER INCISOR IN
CL 2 ,DIV 1 MALOCCLUSION
UPPER INCISOR TO N-A
(LINEAR): NORMAL
ANGLE:4mm
UPPER INCISOR POSITION
8
WILLIAM R. PROFFIT, HENRY W. FIELDS JR., DAVID M.
SARVER,CONTEMORARY ORTHODONTICS, 2006

9. LOWER INCISOR TO N-B ANGLE: INCLINATION OF LOWER CENTRAL
INCISOR
MEAN VALUE:25
INDICATES PROCLINATION OF LOWER INCISORS
DECREASED VALUE INDICATES UPRIGHT OR RETROCLINED LOWER
INCISORS
9
LOWER INCISOR TO N-B (LINEAR): ASSESSING THE
LOWER INCISOR INCLINATION
INCREASED MEASUREMENT INDICATES PROCLINED
LOWER INCISOR
4 mm
WILLIAM R. PROFFIT, HENRY W. FIELDS JR., DAVID M.
SARVER,CONTEMORARY ORTHODONTICS, 2006

10. INTERINCISOR ANGLE: REDUCED
INTERINCISOR ANGLE :CL2 DIV
1/CL1 BIMAX
A LARGER THAN NORMAL
ANGLE IS SEEN IN CL 2,DIV2
MALOCCLUSION
MEAN VALUE:-130-131
10
WILLIAM R. PROFFIT, HENRY W. FIELDS JR., DAVID M.
SARVER,CONTEMORARY ORTHODONTICS, 2006

11. SOFT TISSUE ANALYSIS
S LINE:
LIPS LOCATED BEYOND THIS LINE ARE BELIEVED TO BE PROTRUSIVE
LIPS BEHIND THIS LINE ARE SAID TO BE RETRUSIVE AND THE PATIENT
MAY HAVE CONCAVE PROFILE
11
WILLIAM R. PROFFIT, HENRY W. FIELDS JR., DAVID M.
SARVER,CONTEMORARY ORTHODONTICS, 2006

12. 12
ORTHODONTICS
:KHARBANDA
,DIAGNOSIS AND
MANAGEMENT OF
MALOCCLUSION AND
DENTOFACIAL
DEFORMITIES,2009

13. APPLICABITY
KHARBANDA(1989),SIDHU(1970),KERALA POPULATION BY VALATHAIN
AND JOHN(1976)
INDIANS HAVE SLIGHTLY LARGER VALUE OF ANGLES ANBSUGGESTING
THAT INDIANS POSSESS SLIGHTLY RETRUSIVE MANDIBLE
INCREASED VALUES OF ANGULAR AND LINEAR MEASUREMENTS OF
MAXILLARY INCISOR OF NA AND MANDIBULAR INCISOR TO NB LINE
SUGGEST PROCLINED INCISORS AND FORWARD PLACEMENT OF
INCISORS IN RELATION TO NA NB LINE.THESE FINDINGS ARE MORE
PROMINENT AMONG POPULATION GROUP FROM KERALA
13
ORTHODONTICS:KHARBANDA ,DIAGNOSIS AND
MANAGEMENT OF MALOCCLUSION AND
DENTOFACIAL DEFORMITIES,2009

14. CEPHALOMETRIC NORMS FOR MEWARI CHILDREN USING STEINER'S ANALYSIS.
SINGH RATHORE A1, DHAR V2, ARORA R3, DIWANJI A4, INT J CLIN PEDIATR
DENT. 2012 SEP;5(3):173-7.
The result of this study showed that the Mewari children had
retrusion of mandible relative to cranial base, proclined
maxillary and mandibular teeth, with greater convexity of face.
They also showed anteriorly placed occlusal plane to cranium
and Less prominent chin. In conclusion, these ethnic differences
should be considered during orthodontic treatment.
14

15. TWEED’S ANALYSIS
MAKES USE OF THREE PLANES THAT FORMS DIAGNOSTIC TRIANGLE
A) FRANKFORT HORIZONTAL PLANE
B)MANDIBULAR PLANE
C)LONG AXIS OF LOWER INCISOR
FRANKFORT MANDIBULAR PLANE ANGLE:
FORMED BY INTERSECTIONOF FRANKFORT HORIZONTAL PLANE WITH
THE MANDIBULAR PLANE
MEAN VALUE:25
15
WILLIAM R. PROFFIT, HENRY W. FIELDS JR., DAVID M.
SARVER,CONTEMORARY ORTHODONTICS, 2006

16. 16
WILLIAM R. PROFFIT, HENRY W. FIELDS JR., DAVID M.
SARVER,CONTEMORARY ORTHODONTICS, 2006

17. INCISOR MANDIBULAR PLANE(IMPA)
ANGLE FORMED BY INTERSECTION OF LONG AXIS OF LOWER INCISOR
WITH MANDIBULAR PLANE
INCLINATION OF LOWER INCISOR
MEAN VALUE:90
17
WILLIAM R. PROFFIT, HENRY W. FIELDS JR., DAVID M.
SARVER,CONTEMORARY ORTHODONTICS, 2006

18. FRANKFORT MANDIBULAR INCISOR ANGLE(FMIA)
ANGLE FORMED BY INTERSECTION OF LONG AXIS OF LOWER INCISOR
WITH F.H PLANE
MEAN VALUE:65
18
WILLIAM R. PROFFIT, HENRY W. FIELDS JR., DAVID M.
SARVER,CONTEMORARY ORTHODONTICS, 2006

19. KHARBANDA et al:SAMLPLE OF NORTH INDIAN ADULTS :CLASS 1
OCCLUSION+BALANCED FACIAL PROFILE:FMA CLOSE TO
TWEED’S NORM
REPORTED MEAN FMA OF 23.94,IMPA VALUES RANGED FROM
81-117 WITH A MEAN OF 101.77
FMIA :56-74
19
ORTHODONTICS:KHARBANDA ,DIAGNOSIS AND
MANAGEMENT OF MALOCCLUSION AND
DENTOFACIAL DEFORMITIES,2009

20. APPLICABILITY
Sleep-disordered breathing: choosing the
right cephalometric analysis.
Vezina JP, Blumen M, Buchet I, Chabolle F.
J Oral Maxillofac Surg. 2012 Jun;70(6)
Comparative cephalometric study between nasal and predominantly
mouth breathers.
Frasson JM, Magnani MB, Nouer DF, de Siqueira VC, Lunardi N.
Braz J Otorhinolaryngol. 2006 Jan-Feb;72(1):72-81.
20

21. DOWN’S ANALYSIS
SKELETAL PARAMETERS
FACIAL ANGLE: AVERAGE
VALUE:87.8
RANGE INDICATES 82-95
ANGLE INDICATES ANTERO
POSTERIOR POSITIONING OF
MANDIBLE IN RELATION TO UPPER
FACE
VALUE INCREASES IN CASES OF
SKELETAL CL 3 WITH PROMINENT
CHIN WHILE DECREASE IN SKELETAL
CL 2 CASES
21
T RAKOSI,AN ATLAS AND MANUAL OF
CEPHALOMETRIC RADIOGRAPHY,2 ND ED

22. ANGLE OF CONVEXITY:
AVERAGE VALUE:0
RANGE :-8.5-10
POSITIVE ANGLE OR INCREASED
ANGLE:PROMINENT MAXILLARY
DENTURE BASE RELATIVE TO MANDIBLE
DECREASED:NEGATIVE ANGLE IS
INDICATVE OF A PROGNATHIC PROFILE
22
T RAKOSI,AN ATLAS AND MANUAL OF
CEPHALOMETRIC RADIOGRAPHY,2 ND ED

23. A-B PLANE ANGLE: MEAN VALUE:-4.6
RANGE:-9-0
ANGLE IS INDICATIVE OF MAXILLO-
MANDIBULAR RELATIONSHIP IN RELATION
TO FACIAL PLANE
USUALLY NEGATIVE IN VALUE SINCE POINT
B IS POSITIONED BEHIND POINT A
CL 3 MALOCCLUSION A POSITIVE ANGLE
MAY BE FOUND
23
T RAKOSI,AN ATLAS AND MANUAL OF
CEPHALOMETRIC RADIOGRAPHY,2 ND ED

24. Y-AXIS:
MEAN VALUE:59
RANGE :53-66
ANGLE IS LARGER IN CL 2FACIAL
PATTERNS THAN IN CL 3
PATTERNS
INDICATES GROWTH PATTERN IN
INDIVIDUAL
ANGLE IS SMALLER THAN
NORMAL ,GREATER
HORIZONTAL GROWTH OF
MANDIBLE
24
T RAKOSI,AN ATLAS AND MANUAL OF
CEPHALOMETRIC RADIOGRAPHY,2 ND ED

25. DENTAL PARAMETERS
CANT OF OCCLUSAL PLANE: ANGLE
IS FORMED BETWEEN THE
OCCLUSAL PLANE AND F.H PLANE
DOWNS CONSTRUCTED THE
OCCLUSAL PLANE BY BISECTING
THE OCCLUSION OF 1 ST
PERMANENT MOLARS AND INCISOR
OVERBITE
MEAN VALUE:9.3
RANGE:1.5-14
ANGLE GIVES US A MEASURE OF
THE SLOPE OFOCCLUSAL PLANE AN
F.H PLANE
25
T RAKOSI,AN ATLAS AND MANUAL OF
CEPHALOMETRIC RADIOGRAPHY,2 ND ED

26. INTER INCISAL ANGLE: AVERAGE
READING:135.4
RANGE:130-150.5
ANGLE IS DECREASED IN CL 1
BIMAXILLARY PROTRUSION,CL 2 DIV
1 MALOCCLUSION
INCREASED IN CL 2 DIV 2 CASE
26
T RAKOSI,AN ATLAS AND MANUAL OF
CEPHALOMETRIC RADIOGRAPHY,2 ND ED

27. INCISOR OCCLUSAL PLANE ANGLE:
AVERAGE VALUE:14.5
RANGE :3.5-20
INCREASE IN THIS ANGLE IS SUGGESTIVE OF INCREASED LOWER
INCISOR PROCLINATION
27
T RAKOSI,AN ATLAS AND MANUAL OF
CEPHALOMETRIC RADIOGRAPHY,2 ND ED

28. INCISOR MANDIBULAR PLANE
ANGLE:
MEAN ANGULATION:1.4
RANGE:-8.5-7
INCREASE IN THIS ANGLE IS
INDICATIVE OF LOWER INCISOR
PROCLINATION
28
T RAKOSI,AN ATLAS AND MANUAL OF
CEPHALOMETRIC RADIOGRAPHY,2 ND ED

29. UPPER INCISOR TO A-POG
DISTANCE IS ON AN AVERAGE 2.7mm (RANGE -1 TO 5mm)
MEASUREMENT IS MORE IN PATIENTS PRESENTING WITH UPPER
INCISOR PROCLINATION
29
T RAKOSI,AN ATLAS AND MANUAL OF
CEPHALOMETRIC RADIOGRAPHY,2 ND ED

30. 30
ORTHODONTICS:KHARBANDA ,DIAGNOSIS AND MANAGEMENT OF
MALOCCLUSION AND DENTOFACIAL DEFORMITIES,2009

31. APPLICABILTY
31
DOWN’S NORMS FOR INDIANS WERE INVESTIGATED BY KOTAK(1964),RAVI
NANDA(1969),SIDHU(1970),VALIATHAN(1975),KHARBANDA(1989,1990)
ALL OBSERVED INDIAN FACES POSSESS RACIAL CHARACTERISITICS IN DENTAL
PATTERN
POPULATION GROUP:
NORTH INDIANS:FACIAL SKELETON HAVE A SLIGHTLY HIGHER VALUE FOR Y AXIS
AND ANGLE OF CONVEXITY
KERALITES:SKELETAL PATTERN WHICH IS DIFFERENT FROM NORTH INDIANS AND
CERTAINLY SHOWS GREATER DIFFERENCES FROM CAUCASIANS
KERALITES:MORE VERTICAL FACIAL PATTERN
AB PLANE=N-POG ANGLE IS MORE FOR THEM WHICH ISS CONTRIBUTED BY A
RETRUSIVE MANDIBLE DUE TO VERTICAL PATTERN AND SUPERIOR PROTRUSION
ORTHODONTICS:KHARBANDA ,DIAGNOSIS AND MANAGEMENT OF MALOCCLUSION AND
DENTOFACIAL DEFORMITIES,2009

32. ERRORS IN CEPHALOMETRY
RADIOGRAPHIC PROJECTIONS ERRORS:
MAGNIFICATION: A CERTAIN AMOUNT OF ENLARGEMENT IS SEEN IN
CEPHALOMETRIC RADIOGRAPHS
DISTORTIONS: THE HEAD BEING 3 DIMENSIONAL CAUSES DIFFERENT
MAGNIFICATION AT DIFFERENT DEPTHS OF FIELD .THIS MAY RESULT IN
DISTORTIONS
CAUSES OF ERRORS:
MAGNIFIACTION ERRORS ARE BECAUSE THE XRAY BEAMS ARE NOT PARALLEL
WITH ALL POINTS OF THE OBJECT
LANDMARKS AND STRUCTURES ARE NOT SITUATED IN MIDSAGITTAL PLANE ARE
USUALLY BILATERAL AND MAY CAUSE DUAL IMAGES IN RADIOGRAPHS
ROTATION OF THE PATIENT’S HEAD IN ANY PLANE OF SPACE IN THE
CEPHALOSTATS MAY PRODUCE LINEAR AND ANGULAR DISTORTIONS
32
REF:GRABER,VANARSDALL,VIG,ORTHODONTICS,PRINCIPLES AND PRACTICE,4th ed

33. HOW TO MINIMIZE ERRORS:
BY USING A LONG FOCUS –OBJECT DISTANCE AND A SHORT OBJECT FILM –
DISTANCE
BY USE OF ANGULAR RATHER THAN LINEAR MEASUREMENTS
THIS ERROR MAY BE OVERCOME BY RECORDING THE MIDPOINT OF TWO
IMAGES
BY STANDARDIZED HEAD ORIGINATING USING EAR RODS ,ORBITAL POINTER
AND FOREHEAD REST
ERRORS WITHIN THE MEASURING SYSTEM
ERRORS MAY OCCUR IN THE MEASUREMNET OF VARIOUS LINEAR AND
ANGULAR MEASUREMENTS
HUMAN ERROR MAY CREEP IN DURING THE TRACING AND MEASUREMENTS
THE USE OF COMPUTERIZED PLOTTERS AND DIGITIZE THE LANDMARKS AND
TO CARRY OUT THE VARIOUS LINEAR AND ANGULAR MEASUREMENTS HAS
PROVED TO BE MORE ACCURATE AND CONSISTENT
33
REF:GRABER,VANARSDAL,VIG,ORTHODONTICS,PRINCIPLES AND PRACTICE,4th ed

34. ERRORS IN LANDMARK IDENTIFICATION
QUALITY OF RADIOGRAPHIC IMAGES:POOR DEFINITION OF RADIOGRAPHS MAY OCCUR
DUE TO FAST FILMS AND INTENSIFYING SCREENS ALTHOUGH THE RADIATION DOSE IS
REDUCED
BLURRING OF RADIOGRAPH MAY OCCUR AS A RESULT OF SCATTERED RADIATION THAT
FOGS THE FILM
POOR CONTRAST OF FILM MAY MAKE DIFFERENTIATION BETWEEN ADJACENT
STRUCTURES IS DIFFICULT
HOW TO MINIMIZE:
RECOMMENDED FILMS SHOULD BE USED TO AVOID POOR DEFINITIONS RADIOGRAPHS
THIS AVOIDED BY STABILIZATION OF THE OBJECT ,TUBE,AND FILM
BY INCREASING THE CURRENT ,THE EXPOSURE TIME IS REDUCED ,THUS MINIMIZING THE
POSSIBILTY OF MOTION BUR
THIS CAN BE REDUCED BY USE OF GRIDS
GOOD CONTRAST IS OBTAINED BY USING GOOD FILMS AND USE OF ADEQUATE KV
LEVEL
TOO HIGH KV RESULTS IN POOR CONTRAST
34
REF:GRABER,VANARSDALL,VIG,ORTHODONTICS,PRINCIPLES AND PRACTICE,4th ed

35. PRECISION OF LANDMARK DEFINITION AND REPRODUCIBILITY OF
LANDMARK LOCATION
ERRORS MAY OCCUR IF THE LANDMARK IS NOT DEFINED ACCURATELY
THIS CAUSES CONFUSION IN IDENTIFICATION OF A LANDMARK
IN GENERAL CERTAIN LANDMARKS ARE DIFFICULT TO IDENTIFY
HOW TO MINIMIZE:
LANDMARKS HAVE TO BE ACCURATELY DEFINED
CERTAIN LANDMARKS MAY REQUIRE SPECIAL CONDITIONS TO IDENTIFY
WHICH SHOULD BE STRICTLY FOLLOWED
GOOD QUALITY RADIOGRAPHS AND USE OF AVERAGE VALUES FROM
MULTIPLE IDENTIFICATION OF THE SAME LANDMARKS
OPERATOR BIAS:
VARIATIONS HAVE BEEN OBSERVED IN LANDMARK IDENTIFICATION
BETWEEN OPERATORS
THE OPERATORS EXPECTATIONS CAN RESULT IN BIAS OF VALUES
35
REF:GRABER,VANARSDALL,VIG,ORTHODONTICS,PRINCIPLES AND PRACTICE,4th ed

36. IT IS ADVISABLE FOR THE SAME PERSON TO DENTIFY AND TRACE IN
PATIENTS WHO ARE SUBJECT TO SERIAL CEPHALOMETRIC STUDIES
THIS CAN BE OVERCOME BY RANDOMIZING THE RECORDED
MEASUREMENTS AND BY ADOPTING A DOUBLE BLIND STUDY PATTERN
36
REF:GRABER,VANARSDAL,VIG,ORTHODONTICS,PRINCIPLES AND PRACTICE,4th ed

37. RECENT ADVANCES IN
CEPHALOMETRY
COMPUTER AIDED CEPHALOMETRY: streamline the laborious
manual measurement of dimensions and angular relationships
on patient cephalograms and also have made it much easier to
create and use VTOs
THREE DIMENSIONAL CEPHALOMETRY:
spiral multi-slice (MS) computed tomography (CT)
is innovative 3D virtual approach is a bridge between
conventional cephalometry and modern craniofacial imaging
techniques and provides high-quality, accurate, and reliable
quantitative 3D data.
37
GRABER,VANARSDAL,VIG,ORTHODONTICS,PRINCIPLES AND PRACTICE,4th ed
Swennen GR, schutyser f,three-dimensional cephalometry: spiral multi-slice vs cone-beam
computed tomography, am J orthod dentofacial orthop 2006 sep;130(3):410-6

38. CONCLUSION
THUS KNOWING THE CEPHALOMETRIC ANALYSIS IS AN IMPORTANT
ASPECT OF DIAGNOSING MALOCCLUSIONS AND DESIGNING
TREATMENT PLAN ALONG WITH COMPARISON OF THE PRE OPERATIVE
CONDITIONS AND POST OPERATIVE RESULTS
38

39. REFERENCES
Sleep-disordered breathing: choosing the right ,.Vezina JP, blumen M,
buchet I, chabolle F.,J oral maxillofac surg. 2012 jun;70(6)
Comparative cephalometric study between nasal and predominantly
mouth breathers.,Frasson JM, magnani MB, nouer DF, de siqueira VC,
lunardi N.,Braz J otorhinolaryngol. 2006 jan-feb;72(1):72-81.
Orthodontics:kharbanda ,diagnosis and management of malocclusion
and dentofacial deformities,2009
39

40. GRABER,VANARSDAL,VIG,ORTHODONTICS,PRINCIPLES AND
practice,4th ed
Cephalometric norms for mewari children using steiner's analysis.
Singh rathore A, dhar V, arora R diwanji A, int J clin pediatr
dent. 2012 sep;5(3):173-7.
T rakosi,an atlas and manual of cephalometric radiography,2 nd ed
William r. Proffit, henry w. Fields jr., David m. Sarver,contemorary
orthodontics, 2006
40