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Burstone Analysis /certified fixed orthodontic courses by Indian dental academy
1. BURSTONE ANALYSIS
INDIAN DENTAL ACADEMY
Leader in continuing dental education
www.indiandentalacademy.com
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2. Burstone
Analysis
Guided By:Dr. (Mrs.) P.V. Hazarey
Prof. and Head
Presented By:Dr. V.S. Kohli
Achint Chachada
Prof. and Guide
P.G. Student
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3. introduction
☺Charles J. Burstone et al (1978, 1980) developed an
analysis specially designed for patients requiring
Orthognathic surgery.
☺They used the landmarks and the measurements
that can be altered by common surgical
procedures.
☺This analysis is also called as Cephalometrics for
Orthognathic Surgery (COGS)
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4. introduction
☺COGS system describes the horizontal and vertical
positions of the facial bones by the use of constant
coordinate systems as follows:
☺Size of the bone are represented by direct linear
measurements.
☺Shape of the bones are represented by the angular
measurements.
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5. characteristics
☺Chosen landmarks and measurements can be
altered by various surgical procedures.
☺This analysis includes all the facial bones and a
cranial base reference.
☺Critical facial skeletal components are measured.
☺Measurements used, can be readily transferred to
mock surgery.
☺This systemized approach to measurements can be
computerized.
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6. sKeLetaL and dentaL
anaLysis
☺Landmarks
☺Sella (S) - The center of Pituitary
Fossa
☺Nasion (N) – The most anterior
point of the nasofrontal suture in
the midsagittal plane
☺Anterior Nasal Spine (ANS) – The
anterior most midsagittal point on
the tip of sharp bony process of
maxilla
☺Subspinale (A) – The deepest
midsagittal point on the concavity
between Anterior Nasal Spine and
Prosthion
☺Supramentale (B) – The deepest
point in mid sagittal plane on the
concavity between infradentale and
pogonion
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7. sKeLetaL and dentaL
anaLysis
☺Landmarks
☺Pogonion (Pg) – Most anterior mid
sagittal point on the contour of the
chin
☺Gnathion (Gn) – Constructed by
bisecting the Facial plane and
tangent to lower border of mandible
☺Menton (Me) – Most inferior point
on the inferior contour of the chin
☺Pterygomaxillary fissure (Ptm) –
The most posterior point on the
anterior contour of the maxillary
tuberosity
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8. sKeLetaL and dentaL
anaLysis
☺Landmarks
☺Posterior Nasal Spine (PNS) – The
most posterior point on the contour
of the palate.
☺Articulare (Ar) – The intersection of
basisphenoid and the posterior
border of the condyle
☺Gonion (Go) – constructed by
bisecting the posterior ramal plane
and mandibular plane.
☺Mandibular Plane (MP) – It is the
line joining Gonion and Gnathion
☺Nasal Floor (NF) – A plane
constructed by joining ANS and
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PNS
9. sKeLetaL and dentaL
anaLysis
☺Reference plane
☺The base line used for comparison
of most of the data in this analysis is
a constructed plane called as
Horizontal Plane (HP)
☺Most measurements in this analysis
will be made either parallel to or
perpendicular to this Horizontal
Plane.
☺It is constructed by drawing a line 70
from SN, intersecting at N
HP
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13. sKeLetaL and dentaL
anaLysis
☺Cranial Base Length
☺Cranial base length is measured by
measuring the distance between Ar
and N
☺It is measured parallel to HP
☺This measurement should not be
considered as an absolute value
☺The measurement Ar to N is a
relatively stable anatomical plane,
however it can be changed by
cranial surgery
HP
☺Le Forte II and Le Forte III surgery
changes position of N
☺Autorotation of Mandible changes
position of Ar www.indiandentalacademy.com
14. sKeLetaL and dentaL
anaLysis
☺Cranial Base Length
☺Two measurements are considered
in Cranial Base length – Ar-Ptm and
Ptm-N
☺Ar-Ptm is the distance between Ar
and Ptm which is measured parallel
to HP
☺Standard Value
☺MALES
37.1 + 2.8 mm
☺FEMALES 32.8 + 1.9 mm
☺Ar-Ptm indicates the position of
mandible in relation to posterior
surface of maxilla
HP
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15. SKELETAL And dEnTAL
AnALySiS
☺Cranial Base Length
☺Ptm-N is the distance between Ptm
and N which is measured parallel to
HP
HP
☺Standard Value
☺MALES
52.8 + 4.1 mm
☺FEMALES 50.9 + 3 mm
☺Ptm-N indicates the position of
posterior border of maxilla in
relation to Nasion
☺If this value increases it indicates
more posterior position of maxilla
in relation to N and if it decreases it
indicates anterior position of
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maxilla in relation to N
16. SKELETAL And dEnTAL
AnALySiS
☺Horizontal Skeletal Profile Analysis
☺A few simple measurements should be made on
the skeletal profile to assess the amount of
discrepancy in anteroposterior direction.
☺It is called as Horizontal Skeletal Profile analysis
because all the measurements in this set of analysis
are made parallel to HP
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17. SKELETAL And dEnTAL
AnALySiS
☺Horizontal Skeletal Profile
Analysis
☺ANGLE OF SKELETAL
CONVEXITY
☺It is the angle formed between N-A
and A-Pg
☺Standard Value
☺MALES
3.90 + 6.40
☺FEMALES 2.60 + 5.10
☺A positive angle indicates convex
profile while negative angle
indicates concave profile
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18. SKELETAL And dEnTAL
AnALySiS
☺Horizontal Skeletal Profile
Analysis
☺N Perpendicular to A, parallel
to HP
☺A perpendicular to HP is dropped
from N (N perpendicular) and
horizontal distance parallel to HP is
measured from point A
☺Standard Value
☺MALES
0 + 3.7 mm
☺FEMALES -2 + 3.7 mm
☺This measurement describes the
position of apical base of maxilla in
relation to nasion www.indiandentalacademy.com
19. SKELETAL And dEnTAL
AnALySiS
☺Horizontal Skeletal Profile
Analysis
☺N Perpendicular to B, parallel
to HP
☺It is obtained by measuring the
distance between Point B and
Nasion perpendicular (N
perpendicular)
☺Standard Value
☺MALES
-5.3 + 6.7 mm
☺FEMALES -6.9 + 4.3 mm
☺This measurement describes the
position of apical base of mandible
w
in relation to nasionww.indiandentalacademy.com
20. SKELETAL And dEnTAL
AnALySiS
☺Horizontal Skeletal Profile
Analysis
☺N Perpendicular to Pg, parallel
to HP
☺It is obtained by measuring the
distance between Pogonion and
Nasion perpendicular (N
perpendicular)
☺Standard Value
☺MALES
-4.3 + 8.5 mm
☺FEMALES -6.5 + 5.1 mm
☺This measurement describes the
position of mandibular chin in
relation to nasion www.indiandentalacademy.com
21. SKELETAL And dEnTAL
AnALySiS
☺Vertical Skeletal Analysis
☺A Vertical skeletal discrepancy may reflect an
anterior, posterior or complex dysplasia of the face
☺It is divided into two components
☺Anterior component
☺Posterior component
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22. SKELETAL And dEnTAL
AnALySiS
☺Vertical Skeletal Analysis
☺N-ANS perpendicular to HP
☺Distance between N and ANS
measured perpendicular to HP gives
us the Middle third facial height.
☺Standard Value
☺MALES
54.7 + 3.2 mm
☺FEMALES 50 + 2.4 mm
☺Any increase or decrease in this
value indicates increased or
decreased middle third facial height
respectively
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23. SKELETAL And dEnTAL
AnALySiS
☺Vertical Skeletal Analysis
☺ANS-Gn perpendicular to HP
☺Distance between ANS and Gn
measured perpendicular to HP gives
us the Lower third facial height.
☺Standard Value
☺MALES
68.6 + 3.8 mm
☺FEMALES 61.3 + 3.3 mm
☺Any increase or decrease in this
value indicates increased or
decreased lower third facial height
respectively
HP ||
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24. SKELETAL And dEnTAL
AnALySiS
☺Vertical Skeletal Analysis
☺PNS-N, perpendicular to HP
☺Distance between PNS and HP
gives us the posterior maxillary
height.
☺Standard Value
☺MALES
53.9 + 1.7 mm
☺FEMALES 50.6 + 2.2 mm
☺Any increase or decrease in this
value indicates increased or
decreased posterior maxillary
height respectively
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HP
HP ||
25. SKELETAL And dEnTAL
AnALySiS
☺Vertical Skeletal Analysis
☺MP – HP Angle
☺Mandibular plane angle in relation
to Horizontal plane intersecting at
Gn gives us posterior divergence of
mandible
☺Standard Value
☺MALES
230 + 5.90
☺FEMALES 24.20 + 50
☺This angle relates posterior facial
divergence with respect to anterior
HP ||
facial height
☺Any increase or decrease in value
suggests increasedwww.indiandentalacademy.com
or decreased
posterior facial divergence
26. SKELETAL And dEnTAL
AnALySiS
☺Vertical Dental Analysis
☺Upper 1 to NF
☺To obtain upper anterior dental
height, perpendicular distance from
incisal edge of upper incisor to NF is
measured
☺Standard Value
☺MALES
30.5 + 2.1 mm
☺FEMALES 27.5 + 1.7 mm
☺Any increase or decrease in this
value indicates increased or
decreased upper anterior dental
height respectively
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27. SKELETAL And dEnTAL
AnALySiS
☺Vertical Dental Analysis
☺Lower 1 to MP
☺To obtain lower anterior dental
height, perpendicular distance
between incisal edge of lower
incisor to MP is measured
☺Standard Value
☺MALES
45 + 2.1 mm
☺FEMALES 40.8 + 1.8 mm
☺Any increase or decrease in this
value indicates increased or
decreased lower anterior dental
height respectively
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28. SKELETAL And dEnTAL
AnALySiS
☺Vertical Dental Analysis
☺Upper 6 to NF
☺To measure upper posterior dental
height a perpendicular line is
dropped from the tip of mesiobuccal
cusp of upper first molar to NF
☺Standard Value
☺MALES
26.2 + 2.0 mm
☺FEMALES 23 + 1.3 mm
☺Any increase or decrease in this
value indicates increased or
decreased upper posterior dental
height respectively
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29. SKELETAL And dEnTAL
AnALySiS
☺Vertical Dental Analysis
☺Lower 6 to MP
☺To measure lower posterior dental
height a perpendicular line is
dropped from the mesiobuccal cusp
of lower first molar to MP
☺Standard Value
☺MALES
35.8 + 2.6 mm
☺FEMALES 32.1 + 1.9 mm
☺Any increase or decrease in this
value indicates increased or
decreased lower posterior dental
height respectively
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30. SKELETAL And dEnTAL
AnALySiS
☺Maxilla and Mandible
☺ANS to PNS
☺ANS and PNS are projected on HP
☺Distance between these two points
on HP gives us total effective
maxillary length
☺Standard Value
☺MALES
57.7 + 2.5 mm
☺FEMALES 52.6 + 3.5 mm
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31. SKELETAL And dEnTAL
AnALySiS
☺Maxilla and Mandible
☺Ar to Go
☺Mandibular ramal length is the
linear distance between Articulare
and Gonion
☺Standard Value
☺MALES
52 + 4.2 mm
☺FEMALES 46.8 + 2.5 mm
☺Variation in Ramal length can be a
causative factor for skeletal open
bite or deep bite
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32. SKELETAL And dEnTAL
AnALySiS
☺Maxilla and Mandible
☺Go to Pg
☺Mandibular body length is the
linear distance between Gonion and
Pogonion
☺Standard Value
☺MALES
83.7 + 4.6 mm
☺FEMALES 74.3 + 5.8 mm
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33. SKELETAL And dEnTAL
AnALySiS
☺Maxilla and Mandible
☺Point B to Pg
☺This measurment describes the
prominence of chin in relation to
mandibular apical base
☺It is obtained by measuring the
distance between point B and a
perpendicular to MP passing
through Pg
☺Standard Value
☺MALES
8.9 + 1.7 mm
☺FEMALES 7.2 + 1.9 mm
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34. SKELETAL And dEnTAL
AnALySiS
☺Maxilla and Mandible
☺Ar-Go-Gn Angle (Gonial angle)
☺This measurment represents the
relationship between the ramal
plane and mandibular plane
☺Standard Value
☺MALES
119.10 + 6.50
☺FEMALES 1220 + 6.90
☺Gonial angle also contributes to
skeletal open bite or deep bite
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35. SKELETAL And dEnTAL
AnALySiS
☺Dental parameters
☺OP-HP (Angle)
☺OP is Occlusal Plane constructed
from buccal groove of first
permanent molars through a point
1 mm apical to the incisal edge of
the central incisors
☺When incisors are not in proper
overbite relation, two OP are to be
constructed, upper and lower.
☺Standard Value
☺MALES
6.20 + 5.10
☺FEMALES 7.10 + 2.50
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HP ||
36. SKELETAL And dEnTAL
AnALySiS
☺Dental parameters
☺OP-HP (Angle)
☺An increased OP-HP may be associated with skeletal open
bite, lip incompetence and increased anterior facial height
☺An decreased OP-HP may be associated with skeletal deep
bite, decreased anterior facial height and lip redundancy
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37. SKELETAL And dEnTAL
AnALySiS
☺Dental parameters
☺A-B parallel to OP
☺ This distance is obtained by
measuring the distance between
projection of Point A and Point B on
OP
☺Standard Value
☺MALES
-1.1 + 2.0 mm
☺FEMALES -0.4 + 2.5 mm
☺This distance gives us relationship
between maxillary and mandibular
apical bases in relation to OP
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38. SKELETAL And dEnTAL
AnALySiS
☺Dental parameters
☺Upper 1 to NF (Angle)
☺ This angle is constructed by
intersecting a line passing through
the tip of insical edge through the
root tip of upper incisor and NF line
☺Standard Value
☺MALES
1110 + 4.70
☺FEMALES 112.50 + 5.30
☺This angle gives us the inclination
of upper incisors in relation to
palatal plane (NF)
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39. SKELETAL And dEnTAL
AnALySiS
☺Dental parameters
☺Lower 1 to MP (Angle)
☺ This angle is constructed by
intersecting a line joining the incisal
edge of lower incisor passing
through its root tip and MP
☺Standard Value
☺MALES
95.90 + 5.20
☺FEMALES 95.90 + 5.70
☺This angle gives inclination of lower
incisors in relation to MP
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40. SofT TiSSuE AnALySiS
☺Landmarks
☺Glabella (G) - The most prominent
point in the midsagittal plane of the
forehead
☺Soft tissue nasion (N’)- The point of
greatest concavity in the midline
between the forehead and nose
☺Columella point (Cm) – The most
anterior point on the columella of
the nose
☺Subnasale (Sn) – The point at
which the columella merges with
the upper lip in the midsagittal
plane
☺Labrale superius (Ls) - A point
indicating the mucocutaneous
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border of the upper lip
i
41. SofT TiSSuE AnALySiS
☺Landmarks
☺Stomion superius (Stms)- The
lower most point on the vermilion
border of the upper lip
☺Stomion inferius (Stm )- The upper
i
most point on the vermilion border
of the lower lip
☺Labrale inferius (Li) - A point
indicating the mucocutaneous
border of the lower lip
☺Mentolabial sulcus (Si) – The point
of greatest concavity in the midline
between the Li and Pg’
☺Soft tissue Pogonion (Pog’)- The
most prominent or anterior point
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on the chin in midsagittal plane.
i
42. SofT TiSSuE AnALySiS
☺Landmarks
☺Soft tissue Gnathion (Gn’)- The
constructed midpoint between soft
tissue pogonion and soft tissue
menton
☺Soft tissue Menton (Me’) – lowest
point on the contour of the soft
tissue chin
☺Cervical Point (C) – the innermost
point between the submental area
and neck
i
.
C
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.Gn’
43. Soft tiSSue analySiS
☺Parameters
☺Facial Form
☺Facial Convexity Angle (G-Sn-Pg)
☺Maxillary Prognathism (G-Sn)
☺Mandibular Prognathism (G-Pg)
☺Vertical Height Ratio (G-Sn/Sn-Me)
☺Lower Face Throat Angle (Sn-Gn-C)
☺Lower Vertical height depth ratio (Sn-Gn/C-Gn)
☺Lip position and form
☺Nasolabial Angle (Cm-Sn-Ls)
☺Upper Lip Protrusion (Ls to Sn-Pg)
☺Lower Lip Protrusion (Li to Sn-Pg)
☺Mentolabial Sulcus depth (Si to Sn-Pg)
☺Vertical Lip Chin Ratio (Sn-Stm/Sti-Me)
☺Maxillary Incisor Exposure (Stm U1)
☺Inter labial Gap www.indiandentalacademy.com
44. Soft tiSSue analySiS
☺Facial Form
☺Facial Convexity Angle
☺This angle is formed by intersecting
G-Sn line and Sn-Pg’ line
☺Standard Value
☺120 + 40
☺Any increase or decrease in this
value indicates Convex or Concave
Profile respectively.
☺Maxillary Prognathism
☺Distance between Sn and a line
perpendicular to HP passing
through glabella gives maxillary
prognathism
☺Standard Value
☺6 + 3 mm
☺A negative number suggests
Retrognathism while a large
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positive value suggests Prognathism
45. Soft tiSSue analySiS
☺Facial Form
☺Mandibular Prognathism
☺Distance between Pg and a line
perpendicular to HP passing
through G gives Mandibular
prognathism
☺Standard Value
☺0 + 4 mm
☺A negative number suggests
Retrognathism while a large
positive value suggests Prognathism
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46. Soft tiSSue analySiS
☺Facial Form
☺Vertical Height Ratio
☺It is the ratio between G-Sn (Middle
Facial third) and Sn-Me’ (Lower
Facial third) measured
perpendicular to HP
☺Standard Value
☺1 : 1
☺Increased ratio suggests increased
middle third height and vice versa
☺Lower Face Throat Angle
☺It is the angle formed by
intersection of Sn-Gn’ and Gn’-C
☺Standard Value
☺1000 + 70
☺This angle affects treatment
planning to correct anteroposterior
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facial dysplasia
47. Soft tiSSue analySiS
☺Facial Form
☺Lower face Vertical Height
Depth Ratio
☺It is obtained by dividing Sn-Gn’
distance with C-Gn’ distance
☺Standard Value
☺1.2 : 1
☺A much larger than 1 value
indicates that patient has a
relatively short neck
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48. Soft tiSSue analySiS
☺Lip Position and Form
☺Nasolabial Angle
☺It is the angle formed by
intersection of Cm-Sn line and
Sn-Ls
☺Standard Value
☺1020 + 80
☺Lower than normal Nasolabial
angle suggests proclination of upper
incisors or anterior maxillary base
protrusion or both
☺Higher than normal Nasolabial
angle suggests retroclination of
upper incisors or maxillary base
retrusion or both
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49. Soft tiSSue analySiS
☺Lip Position and Form
☺Upper Lip Protrusion
☺It is perpendicular distance
between Ls to Sn-Pg’ line
☺Standard Value
☺3 + 1 mm
☺Lower Lip Protrusion
☺It is perpendicular distance
between Li to Sn-Pg’ line
☺Standard Value
☺2 + 1 mm
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50. Soft tiSSue analySiS
☺Lip Position and Form
☺Mentolabial Sulcus Depth
☺It is perpendicular distance
between deepest point on the
mentolabial sulcus to Li-Pg’ line
☺Standard Value
☺4 + 2 mm
☺The depth of sulcus is affected by
various factors which are – flared
lower inciors, flaccid lower lip
tone, extruded upper inciors
causing rolling of lower lip, and
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prominence of chin
51. Soft tiSSue analySiS
☺Lip Position and Form
☺Vertical Lip:Chin ratio
☺It is ratio between Sn-Stms and
Stmi-Me’
☺Standard Value
☺0.5 or 1:2
☺Whenever the value decreases
vertical reduction genioplasty
should be considered
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52. Soft tiSSue analySiS
☺Lip Position and Form
☺Maxillary Incisor Exposure
☺It is obtained by measuring the
distance between tip of upper
central incisor and Stms
☺Standard Value
☺2 + 2 mm
☺Increased incisor exposure may be
due to vertical maxillary excess or
short upper lip
☺Decreased incisor exposure may be
due to vertical maxillary deficiency
or larger upper lip www.indiandentalacademy.com
53. Soft tiSSue analySiS
☺Lip Position and Form
☺Inter Labial Gap
☺It is the distance between Stms and
Stmi
☺Standard Value
☺2 + 2 mm
☺Patients with vertical maxillary
excess tend to have large interlabial
gap and lip incompetence
☺Patients with vertical maxillary
deficiency tend to have no Inter
labial gap and Lip redundancy
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54. Summary
This cephalometric analysis is one step
in diagnosis and treatment planning for a
surgical case. It gives the clinician an insight
into the quantitative nature of the skeletodental and also soft tissue dysplasia.
COGS analysis uses linear dimensions to
describe the size and positions of facial bones
and this is practical because surgeon thinks
more in millimeters than in angles for planning
and accomplishing procedures.
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