1. CEPHALOMETRIC ANALYSIS DENT 657

2. 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

3. Morphological Description u Skeletal - horizontal and vertical u Dental - horizontal and vertical u Comparing individual subject’s tracing to the “ideal” u Reference sample Cross-sectional Longitudinal - growth studies eg. Bolton-Brush, Ann Arbor and Burlington

4. Cephalometric Analyses u Down’s u Steiner’s u Tweed’s u McNamara’s u OSU

5. Cephalometric Evaluation u Identification of anatomic landmarks u Landmarks: stable reference structures and maxillary and mandibular skeletal and dental u Graphically relating the dento-facial elements to these reference structures u Angular and or linear measurements

6. METHODS OF CEPHALOMETRIC ANALYSIS u Two basic approaches u Metric approach - use of selected linear and angular measures u Graphic approach - “overlay” of individual’s tracing on a reference template and visual inspection of degree of variation

7. Metric Method - Use of selected linear and angular measures

8. Graphic Method - Use of a Composite Template

9. GOALS OF CEPHALOMETRIC ANLYSIS u Evaluating relationships, both horizontal and vertical of 5 major functional components of the face: u the cranial base; u the maxilla; the mandible, u the maxillary and mandibular dento- alveolus

10. REFERENCE LINES u Frankfort’s Horizontal (porion to orbitale) u Sella - Nasion line u True horizontal plane u True vertical plane

11. sella nasion porionorbitale Reference Lines

12. SKELETAL HORIZONTAL - MAXILLA SNA 82 ± 2 deg NA TO FH 90 ± 3 deg SNA 82 ± 2 deg NA TO FH 90 ± 3 deg s n a F H

13. SKELETAL HORIZONTAL - MANDIBLE s n b P g F H SNB 80 ± 2 deg N-PG TO FH 88 ± 6 deg SNB 80 ± 2 deg N-PG TO FH 88 ± 6 deg

14. SKELETAL HORIZONTAL - MAXILLA TO MANDIBLE N A B ANB 2 ± 2 deg

15. SKELETAL VERTICAL F H S G N M E G O FH TO GOGN 22 ± 5 deg Y AXIS 59 ± 6 deg LFH 55% OF TFH FH TO GOGN 22 ± 5 deg Y AXIS 59 ± 6 deg LFH 55% OF TFH

16. DENTAL - UPPER TO LOWER INCISOR INTERINCISAL 130 ± 5 deg

17. DENTAL - MAXILLARY INCISOR F H N A U1 TO FH 110 ± 5 deg U1 TO NA 22deg U1 TO NA 4mm U1 TO FH 110 ± 5 deg U1 TO NA 22deg U1 TO NA 4mm

18. DENTAL - MANDIBULAR ANTERIOR GO GN B N L1 TO NB 25deg L1 TO NB 4mm L1 TO GOGN 91 ± 6deg L1 TO NB 25deg L1 TO NB 4mm L1 TO GOGN 91 ± 6deg

19. SOFT TISSUE NASOLABIAL ANGLE 102 ± 8 deg L.LIP TO E PLANE -2 ±2mm NASOLABIAL ANGLE 102 ± 8 deg L.LIP TO E PLANE -2 ±2mm

20. Limitations of the Metric Method u Stable reference structures are only relatively stable u Validity of landmarks u Error in landmark identification

21. Graphic Method u Template u Changes between 2 time points

22. Superimposition Method - on the cranial base

23. Maxillary and mandibular superimposition

24. Limitations of Cephalometric Analysis u Individual variability u Ethnic variability u Gender variability