Ortho Part II

Paul K. Chu, DDS St. Barnabas Hospital November 21, 2010

REVIEW FROM LAST LECTURE

1 What kinds of steps are the following?

Distal Mesial

Distal Mesial

Moyer’s Analysis Review

1) Take an impression of a child’s MANDIBULAR arch 2) Measure the mesial distal widths of ALL permanent incisors 3) Take the number you get and look at the black row 4) The corresponding number is the mesial distal width you need for the permanent canine- 1st premolar- 2nd premolar i .e . the 3 - 4 -5 ***(Black row) ----this is the distance you measure****

2 Moyer’s Analysis Review

 #1) measure the mesial distal incisal edge width of EACH permanent incisor and add them up

**Let’s say in this case we measured 21mm.** Step 1

Moyer’s Analysis Review

Maxilla  Look at the chart Mandibular Since  The resulting number measured should give you needed 21mm we look widths of the or here. mandibular space needed for permanent canines and 1st and 2nd premolars.

Step 2

3 Moyer’s Analysis Review

Maxilla  You also use the added Mandibular measurements of the mandibular incisors to get predicted MAXILLARY measurements as well!

Step 2

The Dreaded Measurements Lecture

4 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?

Why? Why? Why?

 Why does this patient have increased overjet?  Is it maxilla too far forward? Is it too far back?  Are the maxillary incisors flared too far forward? Are the mandibular incisors retlid?troclined?  Why does this patient have a deep bite?  Is it skeletal? Is it dental?

5 Whatever you do- do NOT memorize now..just try to reason and make sense of these numbers!!!

Structures to Trace

6 Structures to Trace

• #1 - Facial Profile

7 Structures to Trace

•Sella Turcica •Nasal •

8 Structures to Trace

 Ear rod  PTM, - the projected contour on the lateral film; anterior wall represents outline, and the posterior, the anterior curve of the pterygoid process.

9 Structures to Trace

 Maxilla  Upper 1

10 Structures to Trace

 Mandible  Permanent 1st molars  Lower 1

11 12 Facial Outline Sella Turcica Orbit PTM Ear Rod Maxilla Upper 1 Lower 1 Mandible

Now that we have the structures, we can find points!

13 Standard Cephalometric Landmarks

Sella

Porion Orbitale

Articulare ANS A Point B Point Gonion Pogonion PNS Menton Gnathion

Standard Cephalometric Landmarks

Sella Nasion

Porio Orbital n e Articulare ANS A Point B Point Gonion Pogonion PNS Mento Gnathion n  N, nasion - most anterior point of the nasofrontal suture  A, SubspinaleSubspinale--deepest midline point below the  B, Supramentale - most posterior point on the outer contour of the mandibular

14 Nasion

 Can be difficult to see  Very important landmark  Inward notch, or sideways “v”

A & B Point

 A: Most posterior point on the outer contour of the maxillary alveolar process

 B: Most posterior point on the outer contour of the mandibular alveolar process

15 Standard Cephalometric Landmarks

Sella Nasio n Porio Orbital e nArticulare ANS A Point B Point Gonion Pogonion PNS Menton Gnathion

 ANS, anterior nasal spine - tip of the anterior nasal spine  PNS, - tip of the posterior spine of the palate  Pog, pogonion - most anterior point of the bony  Gn, gnathion - midpoint between the most anterior and inferior points on the bony chin  Me, menton - most inferior point on the outline of the symphysis

Standard Cephalometric Landmarks

Sella Nasion

Porion Orbitale ANS A Point B Point Gonion Pogonion PNS Menton Gnathion  Go, gonion - point midway between the most inferior and most posterior points in the  P, porion - uppermost point on the outline of tthehe ear rods of the cephalostat  Or, orbitale - lowermost point on the orbit  PTM, pterygomaxillary fissure - the projected contour on the lateral film; anterior wall represents maxillary tuberosity outline, and the posterior, the anterior curve of the pterygoid process.

16 Nasion

Sella

A Point

B Point

Orbitale PiPorion ANS PNS

17 * Pog, pogonion - most anterior point of the bony chin * Go, gonion - point midway between the most inferior and most posterior points in the angle of the mandible *G* Gn, gnathion --mmidpoi nt b et ween th e mos t an teri or and inferior points on the bony chin * Me, menton - most inferior point on the outline of the symphysis

Gonion Pogonion Menton Gnathion

18 Frequently Used Planes

 The board exam will test you on angles that these points form...it’s from these angles we can determine possible growth patterns.

Frequently Used Planes SN Plane

Frankfort Plane

Palatal Plane

Occlusal Plane

Mandibular Plane

19 Frequently Used Planes SN Plane

Frankfort Plane

Palatal Plane

Occlusal Plane

Mandibular Plane

20 S - N Plane

 From sella to nasion

Frankfort Plane

 Line connecting the superior border of the external auditory meatus with the infraorbital rim. (Po to Or)

21 Palatal Plane

 Line connecting the ANS to PNS.

Occlusal Plane

 The intersection of the upper and lower incisors to the occlusal contact of the upper and lower first molars .

22 Mandibular Plane

 a tangent to the lower border of the mandible  Go to Gn

SN Plane

Frankfort Plane Palatal Plane

Occlusal Plane

Mandibular Plane

23 Cephlhalometric Assessment

Cephalometric Measurements

••ManyMany different analyses 2 MAINMAIN-- STEINERS & DOWNS ••Remember….thisRemember….this is NOT an exact science ••CombineCombine information from ceph with other clinical information to make a diagnosis and treatment plan.

24 DOWNS ANALYSIS

STEINERS ANALYSIS

Reference Measurements are norms

25 Skeletal Measurements

Anteroposterior measurements  SNA (maxilla)  SNB (mandible)  ANB  Wits Vertical measurements  Y axis  Mandibular plane angle

Skeletal AssessmentAssessment--SNASNA

82 Where? Sella to Nasion to A Point SNA: Evaluates maxilla to cranium Norm= 82o

Antero-posterior maxillary assessment

26 Skeletal Assessment -SNB- SNB

Where? Sella to Nasion 80 to B Point SNB: Evaluates mandible to cranium Norm= 80o

Antero-posterior mandibular assessment

Skeletal Assessment -ANB- ANB

2

Where? A point to Nasion to B Point ANB: Evaluates maxilla to mandible. Norm= 2o

Antero-posterior bimaxillary assessment

27 Skeletal Assessment Wits (AO-(AO-BO)BO)

Where? Draw a PERPENDICULAR line from A point to occlusal plane; B point to occlusal plane Wits Measures? saggpyittal discrepancy between the upper and lower Similar to what? Norm: -1, 0, +1 A- N - B

AO BO

28 Skeletal Assessment Y Axis (to Frankfort Horizontal)

Vertical Skeletal Assessment

Where? Sella to Gn; intersect with Frankfort 59 horizontal YAxis Measures? Growth potential

Skeletal Assessment Frankfort Mandibular Plane Angle (FMA)

Vertical Skeletal Assessment

Cephalometric landmarks used in FMA determination: Gonion (Go), point on angle of jaw that is most inferiorly, posteriorly, and outwardly directed Menton (Me), lowest point of contour of mandible symphysis Orbitale (Or), lowest point on margin of orbit Porion (P), midpoint on upper edge of external auditory meatus Frankfort horizontal plane, plane intersecting right and left poria and left orbitale.

29 FMIA; IMPA

FMIA = (()62) An gle between Frankfurt Horizontal and long axis of lower incisor. IMPA = (93) Angle between long axis of lower incisor and Mandibular Plane. FMA = (22 +/ - 3) Angíe between Frankfurt Horizontal and Mandibular Plane.

30 Growth

 Cranial vault: Intramembranous Formation  Intramembranous- No cartilaginous precursors. nvolves the replacemIent of sheet-like connective tissue membranes with bony tissue.

Growth

 Cranial Base: Endochondral  Endochondral ossification involves the replacement of hyaline cartilage with bony tissue. Most of the of the skeleton are formed in this manner.

31 Growth

 Maxilla: Intramembranous  Intramembranous- No cartilaginous precursors, occurs in area of tension- not pressure. Intramembranous ossification involves the replacement of sheet-like connective tissue membranes with bony tissue.

32 Growth

 Mandible: Intramembranous & Endochondral!!!!! -condylar growth is appositonal - other areas apposition & remodelling

ReviewReview-- Frankfort Mandibular Plane Angle

Angle between Frankfurt Horizontal and Mandibular Plane. Norm: 25o

33 High or Low FMA? High or Low FMA?

Clockwise? Counterclockwise?

34 Long Face Syndrome i.e. Dolichocephaly i.e. Vertical Grower i.e. Clockwise Growth

Short Face Syndrome i.e. Brachiocephaly i.e. Horizontal Grower i.e. Counterclockwise GGorowt h

35 Dental Measurements

Dental Measurements

 Now we measure angles TEETH make  Maxillary incisor measurements  Mandibular incisor measurements

36 Dental Assessment U1U1--SNSN Incisal Angulation Assessment

104 Known also as Upper 1 to SN Norm= 104

Dental Assessment L1L1--GoGnGoGn (Man 1 - GoGn)

Incisor Angulation Assessment

Known also as lower 82o 1 to GoGn Norm= 95

9 5

37 Dental Assessment U1U1--L1L1 (Max 1 - Man 1)

Inter-Incisal Angulation Assessment

Known also as Upper 1 to Lower 1 Norm= 130 Smaller Angle= incisor PROCUMBENCY (usually in class I or II 130 patients) Larger Angle= incisor RETROCLINATION (class III patients)

SOFT TISSUE ASSESSMENT

 E Plane

38 Soft Tissue Assessment E Plane CHANGES WITH AGE! A Line drawn from the soft tissue chin to the tip of the nose

-2 mm

Patient One

Standard Patient SNA 82 81 ••ClassClass I/II/III skeletal? SNB 80 75 ANB 2 6 ••Retrusive/Normal/ProtrRetrusive/Normal/Protr Wits -1 3 Y Axis (Steiner) 66 74 usive profile? SN-GoGn 33 41

••GrowthGrowth pattern? Max 1 - SN 104 110 Max 1 – NA (degrees) 22 29 Max 1 – NA (mm) 4 8 Man 1 - GoGn 92 94 Man 1 – NB (degrees) 25 24 Man 1 – NB (mm) 4 5 Max 1 – Man 1 135 129

E Plane -2 4 Adenoids >4 10

39 Answers: Patient One

 Class II skeletal Standard Patient SNA 82 81 SNB 80 75  Protrusive profile ANB 2 6 Wits -1 3  Vertical Growth Y Axis (Steiner) 66 74 SN-GoGn 33 41 Pattern Max 1 - SN 104 110 Max 1 – NA (degrees) 22 29 Max 1 – NA (mm) 4 8 Man 1 - GoGn 92 94 Man 1 – NB (degrees) 25 24 Man 1 – NB (mm) 4 5 Max 1 – Man 1 135 129

E Plane -2 4 Adenoids >4 10

Friday Dec 10th 6:30 P.M.

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