2. Cephalometrics is a technique employing
oriented radiographs for the purpose of
making head measurements.
Purpose of Cephalometrics
• Study craniofacial growth
• Diagnosis
• Planning orthodontic treatment
• Evaluation of treated cases
3. 15"15"60"60"
Source PlaneSource Plane
X-ray SourceX-ray Source
Patient in Head
Positioning Device
Patient in Head
Positioning Device
Mid-saggital PlaneMid-saggital Plane
Film PlaneFilm Plane
X-ray Film in
Cassette
X-ray Film in
Cassette
Cephalostat
6. White Black Israeli Chinese Japanese
SNA 82 85 82 82 81
SNB 80 81 78 79 77
ANB 2 4 4 3 4
U1-NA 4 mm, 22 7 mm, 23 5 mm, 24 5 mm, 24 6 mm, 24
L1-NB 4 mm, 25 10 mm, 34 6 mm, 29 6 mm, 27 8 mm, 31
U1-L1 131 119 124 126 120
GoGn-SN 32 32 35 32 34
L1-MnPl 93 100 93 93 96
L1-FH 62 51 57 57 57
Y axis 61 63 61 61 62
from Proffit,Contemporary Orthodontics, 1992
Cephalometric Values for
Selected Groups
7. What Are We Trying to
Accomplish?
• Find out skeletal classification
– anteroposterior
– vertical
• Find out angulation of incisors
• Consider soft tissue
– facial profile
– airway considerations
8. What Are We Trying to
Accomplish? (In other words)
• Is the patient Class I, II, III skeletal?
• Does the patient have a skeletal open bite
growth pattern, or a deep bite growth
pattern, or a normal growth pattern?
• Are the maxillary/mandibular incisors
proclined, retroclined or normal?
• Is the facial profile protrusive, retrusive, or
straight; can the patient breathe normally?
31. Children with airway obstruction, when
compared to normal controls, show:
Nasorespiratory Considerations
• Increased total and lower face heights
• More retrognathic mandibles
• Steeper (increased) mandibular plane
angles
• Spontaneous improvement after
reestablishment of normal respiration