information and method of steiner analysis for lateral cephalometric analysis

1. Steiners analysis
Dr Nabil Rahman

2.  Cecil c. Steiner(1896-1989)
 One of Edward H.Angle’s first
students in 1921.
 He developed a form of
cephalometric analysis,
presented in 1953,referred to
as the Steiner method of
analysis.

3.  Steiner in his analysis took into account that it may
not be possible to reach ideal proportions and
relationtionships in all cases, but there are ways to
maximize esthetics.
 Steiner devised ways to alter incisor positions to
achieve normal occlusions ever when the ideal ANB
angle couldn’t be achieved. i.e. how much the teeth
needed to be moved to compensate for a skeletal
malocclusion.
 For larger skeletal discrepancies ,the Steiner method
would not be effective for treatment.

4. traditional lateral cephalometric headfilm
landmarks

5. Steiner use SELLA to NASION line as a reference plane for
his analysis. This line represents the anterior cranial base.
Steiner highlighted difficulties in accurate location of the
porion point and its relative variation, which could be
observed in successive radigraphs.This in turn, affected the
orientation of F-H plane.
S and N points have another advantage of being located in
the mid sagittal plane of the head and move minimally with
any any deviation of head from true profile position. The
cranial base undergoes very little change after the age of 6-
7 years.

6.  Skeletal analysis
 Dental analysis
 Soft tissue analysis
Steiner analysis consist of

7. STEINER’S Analysis
SKELETAL DENTAL SOFT
ANALYSIS ANALYSIS TISSUE ANALYSIS
-SNA (Maxilla) -Maxillary incisor position -S line
-SNB (Mandiblar) -Mandibular incisor position
-ANB (Maxillary-Mandibular) -Interincisal angle
-Occlusal plane -Lower incisor to chin
-Mandibular plane

8. Skeletal analysis

9. SNA Angle
-Mean is 82°
-Greater angle indicates
relative forward positioning
of maxilla & lesser angle
indicates recessive location
of maxilla

10. SNB angle
-Mean is 80°
-Angle less than 80
indicates recessive
mandible while greater
angle suggest Prognathic
mandible

11. Relationship of maxilla to
mandible (ANB)
- Angle provides a general idea
of anterioposterior
discrepancy of maxilla to
mandibular apical bases
- Mean is 2°
- Greater than the mean
indicates a class II skeletal
tendency, angle less than 2 &
below zero indicates the
mandible located ahead of
maxilla suggesting class III

12. Relationship of maxilla
to mandible (ANB)
ANB angle tell us only about
“Magnitude of the discrepancy
between the jaws, not the absolute
discrepancy”
If treatment is based on the ideal
ANB angle of 2 degree it may not
necessarily obtain the ideal position
of either the maxilla or the
mandible.
Steiner believed the main interest
should be alleviating the magnitude
of discrepancy.

13. -Occlusal plane drawn through
the region of overlapping cusps of
1st premolars & 1st molars.
-Angle of occlusal plane & S-N is
measured.
-Mean reading is 14°
-The angle is increased in long face
or vertically growing individuals
and also skeletal open bite cases.
- It may be decreased in
horizontally growing individuals
or cases with a skeletal deep bite.
Occlusal plane

14. Mandibular plane (Go-Gn)
- Drawn between gonion & gnathion
- The mandibular plane angle is
formed by joining the mandibular
plane to the anterior cranial base
(S-N plane)
- Mean reading is 32°
- Excessively high or low mandibular
plane angles suggest unfavorable
growth pattern in individuals

15. Dental analysis

16. Dental U1-NA distance
Dental U1-NA angle
 Angle is formed by intersection of
long axis of upper central incisors &
line joining N-A line
 22 degree angle and 4mm distance is
ideal.
 Greater than 22 may be seen in class
II div I .
 Less than 22 degree may be seen in
class II div 2 case.
It is necessary to measure
the distance from the most
labial surface of the
incisor to the NA line.
Measurement >4 mm common in class I bimaxillary protrusion or in class
II div 1 relationship.
Less than 4 mm common in class II div 2 .

17. Incisor angle at 22 degrees but
(a) Retro positioned (-2mm)
(b) Ideally positioned (4mm)
(c) Positioned too far forward (8mm)
Show inadequacy of relating incisor
tip to millimeter reading only.
All three teeth are 4mm from the N-
A line but angled differently

18. LI –NB distance
LI –NB angle
Angle is formed by intersection of long
axis of lower central incisors & line joining
N-AB line
25 degree angle and 4mm distance is ideal
Angle greater than 25 degree may be seen in
class II div 1
Less than 25 degree common in class II div 2
or class III

19. Interincisal angle
 Mean value of 130-131°
 Reduced angle suggest
class II div 1
 Larger angle indicates
class II div 2

20. Lower incisor to chin
(Holdaway ratio)
This measurement is introduced to evaluate the relative prominence
of the mandibular incisors, as compared to the size of the bony chin.
• According to Holdaway distance between
labial surface of Mb incisor to N-B line and
the distance from pogonion to N-B line
should be equal (i.e. 4mm)
• Discrepancy
• If discrepancy is
• 2mm = Acceptable
• 3mm = Less desirable
• 4mm exceeds = Correction indicated

21. Soft tissue analysis
The facial contour line called ‘S’ line of Steiner. A line is drawn on the soft tissue
contour of the chin to the middle of the ‘S’ formed by the lower border of the nose
.In a well balanced face, the lips should touch the line.
If the lips are located beyond this line lips are believed to be
protrusive & interpreted as convex profile
If lip behind this line said to be retrusive with a concave profile.

22. PRINT MASTER

23. What is E line?
In Ricketts analysis E line or estheic
line runs from the tip of the nose to
the soft tissue pogonion.
S line extending from soft tissue contour of the
chin to the middle of an “S” formed by the lower
border of the nose