INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com
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CEPHALOMETRIC ANALYSIS
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ANALYSIS UTILIZING THE CEPHALOMETRIC TRACING 1) Describe the subject’s dento-facial morphology 2) Quantitative description of morphological deviations 3) Make diagnostic and treatment planing decisions 2) Evaluate change over time - treatment induced and growth process
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Morphological Description Skeletal - horizontal and vertical Dental - horizontal and vertical Comparing individual subject’s tracing to the “ideal” Reference sample Cross-sectional Longitudinal - growth studies eg. Bolton-Brush, Ann Arbor and Burlington www.indiandenatalacademy.com
Cephalometric Analyses Down’s Steiner’s Tweed’s McNamara’s OSU
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Cephalometric Evaluation Identification of anatomic landmarks Landmarks: stable reference structures and maxillary and mandibular skeletal and dental Graphically relating the dento-facial elements to these reference structures Angular and or linear measurements www.indiandenatalacademy.com
METHODS OF CEPHALOMETRIC ANALYSIS Two basic approaches Metric approach - use of selected linear and angular measures Graphic approach - “overlay” of individual’s tracing on a reference template and visual inspection of degree of variation www.indiandenatalacademy.com
Metric Method - Use of selected linear and angular measures
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Graphic Method - Use of a Composite Template
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GOALS OF CEPHALOMETRIC ANLYSIS Evaluating relationships, both horizontal and vertical of 5 major functional components of the face: the cranial base; the maxilla; the mandible, the maxillary and mandibular dentoalveolus www.indiandenatalacademy.com
REFERENCE LINES Frankfort’s Horizontal (porion to orbitale) Sella - Nasion line True horizontal plane True vertical plane
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Reference Lines
sella porion
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nasion orbitale
SNA SNA82 82±±22deg deg NA NATO TOFH FH90 90±±33 deg deg
SKELETAL HORIZONTAL MAXILLA
s
n
FH a
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SNB SNB80 80±±22deg deg N-PG N-PGTO TOFH FH 88 88±±66deg deg
SKELETAL HORIZONTAL MANDIBLE
n
s FH
b Pg www.indiandenatalacademy.com
ANB ANB22±±22deg deg
SKELETAL HORIZONTAL MAXILLA TO MANDIBLE
N
A B www.indiandenatalacademy.com
FH FHTO TOGOGN GOGN22 22 ±±55deg deg YYAXIS AXIS59 59±±66 deg deg
SKELETAL VERTICAL
LFH LFH55% 55%OF OFTFH TFH
S FH
GO ME www.indiandenatalacademy.com
GN
INTERINCISAL INTERINCISAL 130 130±±55deg deg
DENTAL - UPPER TO LOWER INCISOR
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U1 U1TO TOFH FH110 110±± 55deg deg U1 U1TO TONA NA22deg 22deg U1 U1TO TONA NA4mm 4mm
DENTAL - MAXILLARY INCISOR
N FH A
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L1 L1TO TONB NB25deg 25deg L1 L1TO TONB NB4mm 4mm L1 L1TO TOGOGN GOGN91 91 ±±6deg 6deg
DENTAL - MANDIBULAR ANTERIOR
N
GO
B GN
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NASOLABIAL NASOLABIAL ANGLE ANGLE102 102±±88 deg deg L.LIP L.LIPTO TOEE PLANE PLANE-2 -2±2mm ±2mm
SOFT TISSUE
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Limitations of the Metric Method Stable reference structures are only relatively stable Validity of landmarks Error in landmark identification
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Graphic Method Template Changes between 2 time points
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Superimposition Method - on the cranial base
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Maxillary and mandibular superimposition
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Limitations of Cephalometric Analysis Individual variability Ethnic variability Gender variability
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www.indiandentalacademy.com Leader in continuing dental education
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