cephalometrics in pediartic dentistry

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CEPHALOMETRICS

CONTENTSINTRODUCTIONHISTORYCEPHALOMETRIC IMAGING SYSTEMUSES OF CEPHALOGRAMGOALS OF CEPHALOGRAMTYPES OF CEPHALOGRAMCEPHELOMETRIC LANDMARKSTRACING TECHNIQUECEPHELOMETRIC PLANEANALYSISCONCLUAIONREFRRENCES

Why cephalometric is imp for pedodontist ????

The American Academy of Pediatric Dentistry (AAPD) recognizes the importance of managing the developing dentition and occlusion and its effect on the well-being of infants, children, and adolescents.

Early diagnosis and successful treatment of developing malocclusions can have both short-term and long-term benefits while achieving the goals of occlusal harmony and function and dentofacial esthetics.AAPD Guideline ,2016

Diagnostic orthodontic records fall into three major categories of evaluation:

(1) health of the teeth and oral structures,

(2) alignment and occlusal relationships of the teeth, &

(3) facial and jaw proportions which includes both cephalometric radiographs and facial photographs.AAPD Guideline ,2016

CMON MAN,I Am Pedodontist. PEDODONTIST

INTRODUCTIONCraniometry measuring skull.

Cephalometry measuring head.

CEPHALOSTAT ?? CEPHALOGRAM ?? CEPHALOMETRICS ??

DEFINATION

The term cephalometric is used to describe the analysis and measurements made on the cephalometric radiograph.

- BHALAJHI (5thedition)

HISTORY The discovery of x-ray in 1895 by ROENTGEN. It is provided a method of obtaining the inner cranio-facial measurements with quite a bit of accuracy and reproducibility.

Roentgen 1st discovered x-ray who was professor at wuerzburg university in Germany.

On December 28, 1895 he submitted a paper On A New Kind of Rays to the Wurzburg.

His first experiment was in 1895 on the film of his wifes hand.

Prof. Wilhem Koening & Dr. Otto Walkhoff made the first dental radiograph in 1896. In 1922, paccini standardized radiographic head images by positioning the subjects against a film cassette at a distance of 2 meters from x-ray tube.

In 1931, Boardbent in U.S.A. and Hofrath in Germany simultaneously presented a standardized cephalometric technique using high powered x-ray machine.

William. B. Downs in 1948 developed the first cephalometric analysis.

Followed by other analyses by Steiner (1930), Tweed (1953), Ricketts (1958), Enlow (1969), Jacobson (1975) etc.

USES OF CEPHALOGRAM

In classification of dental and skeletal abnormalities.

In orthodontic diagnosis & treatment planning.

In evaluation of treatment results.

In predicting growth related changes & changes associated with surgical treatment.

In establishing facial type.

In research work which involves the cranio-dentofacial region.

GOALS OF CEPHALOMETRICS To evaluate the transverse, sagittal & Antero-posterior relationships of the following components of the face:

The Cranium & cranial baseThe Skeletal maxillaThe Skeletal mandibleThe Maxillary dentition & alveolar processThe Mandibular dentition & alveolar processThe Maxilla-Mandibular relationshipThe relation of Maxilla & Mandible to the Cranial base

PROFFIT TEXT BOOK OF ORTHODONTICS,5TH EDITION .

TECHNICAL ASPECTS

The cephalometric radiographs are taken using an apparatus that consists of an x-ray source & a head holding device called cephalostat.

Cephalostat consists of,

2 Ear rods- prevents movement of head in the horizontal plane. Orbital pointer- helps in vertical stabilization of head. This contacts the lower border of the left orbit. Forehead clamp- supports the upper part of face, positioned above the region of the nasal bridge.

BHALAJI TEXT BOOK OF ORTHODONTICS,5TH EDITION ,2012

The distance between the x-ray source & the mid-sagittal plane of the patient is fixed at 5 feet.

Thus, the equipment helps in standardizing the radiographs by use of constant head position and source-film distance, so that serial radiographs can be compared.


CEPHALOGRAM FRONTALLATERALBHALAJI TEXT BOOK OF ORTHODONTICS,5TH EDITION ,2012

Lateral cephalogram :

It provides a lateral view of the skull. and taken with the head in standardized reproducible position at a specified distance from the source of the x-ray.


USES Important in orthodontic growth analysis. Diagnosis and treatment planning. Evaluation of final treatment outcome. Monitoring of therapy.


Frontal cephalogram : It provides the antero-posterior view of the skull.


USES Provide information related to skull width. Skull symmetry Vertical proportions of skull, craniofacial complex and oral structure. For accessing growth abnormalities and trauma.


LANDMARKS

REQUIREMENTS OF LANDMARKS Easily seen in a radiograph. Should be uniform in outline. Should be reproducible. Landmarks should be permit valid quantitative measurements of lines & angles. Lines & planes should have significant relationship to the growth vectors of specific areas.


There are no fixed points in the skull of living person. Depends on age, sex, maturation rate, ethnic background, and other factors.

Landmarks show a range of normal variation. so orthodontist determine whether facial dimensions and relationship fall with in the range of normal variation or not.

Radiographic cephalometry- Alexander Jacobson

CEPHALOMETRIC LANDMARKS A Point on cephalogram that serves as a guide for measurement on construction of planes. LANDMARKSANATOMICDERIVED

CEPHALOMETRIC LANDMARKSHARD TISSUE SOFT TISSUEANATOMICDERIVEDUNILATERALBILATERALBHALAJI TEXT BOOK OF ORTHODONTICS, 5TH EDITION,2012

HARD TISSUE CEPHALOMETRIC LANDMARKSANATOMICDERIVEDNasionAnterior nasal spinePoint A ProsthionInfradentalePoint BPogonionMentonSella

Orbitale

Gonion

Articulare

Gnathion

Anterior point of occlusion

Posterior point of occlusion

Pterygomaxillary fissure

PHULARI TEXT BOOK OF ORTHODONTICS,1st Edition ,2011

Nasion (N) : The most ant. Point midway between the frontal & nasal bone on the fronto-nasal suture.

Orbitale (O) : It is lowest point of the inferior bony margin of the orbit.

Anterior Nasal spine (ANS) : It is ant. Tip of the sharp bony process of maxilla in the midline of the lower margin of ant. Nasal opening.

Posterior nasal spine (PNS) : It is intersection of a continuation of the ant wall of the pterygo-palatine fossa & the floor of the nose, the distal limit of the maxilla.

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Point A : It is the deepest point in the midline between the anterior nasal spine and alveolar crest between two central incisors. Also called subspinale.

Point B : It is the deepest point in the midline between the alveolar crest of mandible & the mental process. Also called supramentale.

Pogonion (Pog) : It is the most ant. Point of the bony chin in the median plane.

Gnathion (Gn) : It is the most Antero-inferior point of the symphysis.

Menton (Me) : It is the most inferior Midline point on the mandibular symphysis.

Sella (S) : The point representing the Midpoint of the pituitary fossa. It is a constructed point in the mid-sagittal plane.

Pterygomaxillary fissure (Ptm) : It is the intersection of the inferior border of the foramen rotundum with the posterior wall of pterygo-maxillary fissure.

Articulare (Ar) : Intersection between the shadow of zygomatic arch and posterior border of ramus.

Basion (B) : It is the median point of anterior margin of the foramen magnum.

Gonion (Go) : It is a constructed point at the junction of ramal plane & mandibular plane.

Condylion (Cd) : The most superior point on the head of the condyle.

Porion (Po) : The highest bony part/point of the upper margin of external auditory meatus.

Bolton point (Bo) : The highest point at the post condylar notch of the occipital bone.


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SOFT TISSUE LANDMARKSGlabellaNasionPronasaleSubnasaleLabial superiusStomion supeperiusStomion inferiusStomionLabial inferiusPogonion soft tissueMenton soft tissue

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Glabella (G) : It is the most prominent point in the midsagittal plane of forhead.

Nasion soft tissue (Ns) : It is the deepest point in the concavity of the soft tissue contour of the root of the nose.

Pronasale (Pn) : The most prominent point of the nose.

Subnasale (Sn) : It is the intersection of the lower border of the nose and the outer contour of upper lip.

Labial superius (Ls) : The median point in the upper margin of the upper membranous lip.

Stomion superius : It is the lowest point of the upper lip.

Stomion inferius : It is the highest point of the lower lip.

Stomion : It is the midpoint between stomion superius and stomion inferius.

Labial inferius : The median point in the lower margin of the lower membranous lip.

Pogonion soft tissue : It is the most prominent point on the soft tissue contour of the chin.

Menton soft tissue : It is a constructed point at the intersection of a vertical co-ordinate from menton and the inferior soft tissue contour of the chin.


A lateral cephalogram.

Acetate matte tracing paper(.003 inches thick, 810 inches).

A sharp 3H drawing pencil or a very fine tipped pen.

tapeRadiographic cephalometry- Alexander Jacobson

Tracing supplies & equipments

A protractor and template. templates for tracing the outlines of ear rods.

Viewbox.

Pencil sharpener and a eraser.Radiographic cephalometry- Alexander Jacobson

General considerations for the tracingStart by placing the cephalogram on the viewbox with the patients image facing towards the right.

Tape the four corners of the radiograph to the viewbox.

Draw three crosses on the radiographs, two within the cranium and one over the area of the cervical vertebrae (registration crosses). Radiographic cephalometry- Alexander Jacobson

Place the matte acetate film over the radiograph and tape it securely.

After that, trace the three registration crosses.

Print the pt name, record number, age in years and months, the date on which the cephalogram was taken and your name on the bottom left corner of the acetate film.

Begin tracing using smooth continuous pressure.Radiographic cephalometry- Alexander Jacobson

CEPHALOMETRIC PLANESVERTICALHORIZONTAL

FRANKFORT Horizontal plane :

F-H Plane is the plane that connects the lowest point of the orbit to the superior point of the external auditory meatus.

It is used to assess horizontal growth during the analysis.

This is the best representation of the basic horizontal plane of the skull.


MANDIBULAR PLANE:

It is the plane that connects the point Menton (Me) to the point Gonion (Go).

For growth pattern assessment.

1. Straight line tangent to the lower most border of the mandible. ( Down) 2. Go Me - Mc Namara - Rakosi - COGS

3. Go Gn - Steinerss

OCCLUSAL PLANE :

This plane is formed by a line connecting anterior point of occlusion to the posterior point of occlusion.

Anatomical occlusal plane

Functional occlusal plane


Se-N PLANE :

It is the plane formed by the line connecting se and Nasion.

It expresses the anteroposterior extent of anterior cranial base.


VERTICAL PLANES

FACIAL Plane :

It is a line from the anterior point of the frontonasal suture (N) to the most anterior point of the mandible (Pog).

Used to record position of chin.And to relate position of maxilla to facial plane.

A-Pog plane: It is a line from point A on the maxilla to pogonion on the mandible.

Also known as Dental plane.

Used in measure position of anterior teeth.

FACIAL AXIS:

A line from ptm point to cephalometric Gnathion.

Direction of growth of the chin. Whether it is horizontal or vertical.

Ar-Go plane:

This plane is formed by the line connecting from Articulare to Gonion.

It is important in the determination of length of ramus.

PALATAL PLANE This plane extends through the ANS to PNS.

The relationship of this plane to FH plane is useful in evaluating treatment changes occurring in the maxilla.Assessment of remaining alveolar bone for implant placement.

E PLANE: (soft tissue)

It is also called as Esthetic plane.

It is also known as RICKETTs esthetic line (By rickett in 1960). Which extends from the tip of the nose to the chin.

The lips should be slightly behind this line for esthetics.

This affects the lips prominency.

MEASUREMENT ANALYSIS DOWNS (1948)STEINERS (1950)WITS APPRAISAL (1952)TWEEDS (1954)COGS (1978)RAKOSIS (1979)Mc NAMARAS (1984) HOLDAWAYS (1984)HARD TISSUE ANALYSISSOFT TISSUE ANALYSIS

DOWNS ANALYSIS (1948)One of the most commonly used analysis.

Downs had based his findings on 20 Caucasian individuals of 12-17 years age group of both sexes.

Downs analysis consists of 10 parameters 5 skeletal and 5 dental.

Radiographic cephalometry- Alexander Jacobson

SKELETAL PARAMETERS Facial angle Angle of convexity A-B Plane Mandibular plane angle Y-axis

F a c i a l A n g l eMean Reading : 87.5oRange : 82o 95oNPogPoOr Facial angle: The intersection of nasion-pogonion plane and the FH plane. This angle gives us an indication of the antero-posterior positioning of the mandible to the cranium. This value increases in cases of skeletal CL-III & it decreases in CL-II casesSkeletal parameter

A n g l e o f C o n v e x i t yMean Reading : 0oRange : -8.5o 10oAngle of convexity: By the intersection of a line from nasion to Point A ,and a line from Point A to pogonion.

This angle gives idea about the convexity or concavity of the skeletal profile. A positive angle or an increased angle shows a prominent maxillary base compared to mandible (retrognathic profile) while a negative or decreased angle shows a prognathic profile.

NAPogSkeletal parameter

A-B PlaneMean Reading : -4.6oRange : -9o - 0o A-B Plane: this angle is formed between a line connecting Point A and Point B ,and a line joining nasion to pogonion.

This angle is indicative of the maxillo-mandibular relationship in relation to the facial plane. In cases of CL-III malocclusions, a positive angle is seen.

NAPogBSkeletal parameter

M a n d i b u l a r P l a n e A n g l eMean Reading : 21.9oRange : 17o 28oFormed by intersection of mandibular plane with FH Plane.

An increased plane is suggestive of a vertical grower.PoOrGoMe

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Y - G r o w t h A x i sMean Reading : 59oRange : 53o 66oThis angle is formed by joining sella-gnathion line with FH plane . This angle is larger in CL-II. It indicates the growth pattern of the individual.If the angle is greater than normal, it indicates greater vertical growth of the mandible. if it is lesser,it indicates horizontal growth of the mandible.PoOrGnSeSkeletal parameter

DENTAL PARAMETERS Cant of occlusion plane Lower incisor to occlusal plane Lower incisor to mandibular plane Interincisal angle Upper incisor to A-point

C a n t o f O c c l u s a l P l a n eMean Reading : 9.3oRange : 1.5o 14o..This angle is formed between occlusal plane and F.H. plane.

This angle gives us a measure of the slope of occlusal plane to F.H. planePoOrOPDental parameter

I n t e r i n c i s a l A n g l eMean reading : 135.4oRange : 130o 150oThis angle is formed between the long axis of upper and lower incisors.

This angle decreases in CL-I bimax.protrusion and CL II Div-I cases.

it increases in CL-II Div-II cases.Deciduous - 151Dental parameter

OPIncisor occlusal plane angleDental parameterMean reading : 14.5oRange : 3.5o 20oThis angle is formed by the long axis of lower central incisor and OP.

This angle Increases is suggestive of increases the lower incisor proclination.

I n c i s o r M a n d i b u l a r P l a n e A n g l eMean reading : 1.4oRange : -8.5o 7oFormed by intersection of long axis of lower incisor and mandibular plane. An increase in this angle is indicative of lower incisor proclination.GoMeDental parameter

This is a measurement between incisal edge of maxillary central incisor and a line joining Point A to pogonion. Average value is 2.7mm range is -1 to 5mm

It is more in patients with upper incisor proclination

Upper incisor to A - Pog lineAPogDental parameter

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TWEEDS ANALYSIS (1954) Tweed used three planes to establish a diagnostic triangle, the three planes used in this analysis are:

Frankfort horizontal planeMandibular planeLong axis of lower incisorRadiographic cephalometry- Alexander Jacobson

FMAFMIAIMPAThe Diagnostic Facial Triangle

Frankfort mandibular incisor angle- 65 (long axis of Lower incisor to FH plane) pedo- 63

Frankfort mandibular plane angle- 25 (FH to MP) pedo 27

Incisor mandibular plane angle-90 (long axis of lower incisor to Mandibular plane) pedo- 90

FMAFMIAIMPA

The value for tweeds analysis :Frankfort mandibular plane angle (FMPA) 25 (16- 35)Incisor mandibular plane angle (IMPA) 90 (85- 95)Frankfort mandibular incisor angle (FMIA) 65 (60-75)

STEINERS ANALYSISDeveloped by Steiner in the 1930s can be considered the first of the modern cephalometric analysis for two reasons:

It displayed measurements in a way that emphasized not just the individual measurements but their interrelationship into a pattern.

Specific guide for use of cephalometric measurements in treatment planning.AJO-1959Radiographic cephalometry- Alexander Jacobson

Steiner analysisSteiner did analysis only on 1 Hollywood starlet. so it is a questionable. But he had very good eye bz recalculation of his original values from larger samples produced only minor changes.

Skeletal analysis Dental analysis Soft tissue analysis

AJO DO-1959

SKELETAL PARAMETERS SNA angle SNB angle ANB angle Mandibular plane angle Occlusal plane angle

S N A A N G L EMean reading : 82o Pedo - 81It is the angle formed by the intersection of SN plane and a line joining from nasion and point A.This angle indicates the relative antero-posterior positioning of maxilla in relation to cranial base.A larger than normal value indicates a prognathic maxilla while a smaller value suggests a retrognathic maxilla.

NASSkeletal parameter

S N B A N G L EMean reading : 80oPedo : 76It is the angle between SN plane and a line joining nasion to Point B. This angle indicates the antero-posterior positioning of the mandible in relation to cranial base.

An increase indicates a prognathic mandible and lesser value suggests retrusive mandible.

NSBSkeletal parameter

ANBA N B A N G L EMean reading : 2oPedo :4This angle is formed by intersection of the lines joining nasion to Point A, and nasion to Point B. It denotes the relative position of maxilla and mandible to each other. An increase is suggestive of CL-II skeletal tendency while lesser than normal suggests CL-III skeletal relationshipSkeletal parameter

Occlusal Plane

Mean reading : 14oFormed between occlusal plane and SN plane.The occlusal plane is represented by a line passing between the overlapping cusps of first premolars and first molars. This angle denotes the relation of occlusal plane to cranium and face.NSOPSkeletal parameter

Mandibular Plane

Mean reading : 32o It is the angle formed between Mandibular plane and SN plane. The mandibular plane is a line connecting gonion and gnathion.

This angle indicates growth pattern; a lower angle suggests a horizontal growing face and increased angle shows a vertical pattern

NSeGoGnSkeletal parameter

DENTAL PARAMETERS Upper incisor to N-A angle Upper incisor to N-A linear Lower incisor to N-A angle Lower incisor to N-B linear Inter-incisor angle

Upper incisor to N-A (angle)- Formed by intersection of long axis of upper centrals and line joining nasion to point A. It indicates the relative inclination of upper incisors; increased angle is seen during proclination.

Upper incisor to N.A (Linear)- It is a linear measurement formed between labial surface of upper central incisor and a line joining nasion to Point A. This value helps in determining upper incisor position. it increases in proclined upper incisors.

Dental parameterPedo-4 mm24

Lower incisor to N.B (angle)- Formed between N-B plane and long axis of lower incisor. It shows us the inclination of lower central incisor; an increased value shows proclined incisor and decreased angle gives retroclined incisor. Lower incisor to N.B (Linear)- It is the linear distance between Labial surface of lower central incisor and a line joining nasion to Point B. It helps us to assess lower incisor inclination; increased value shows proclination and vice-versa

Dental parameterpedo4 mm26

Mean reading : 130o151 - pedoI N T E R I N C I S A L A N G L E Interincisal angle- Formed between long axis of upper central and long axis of lower central incisors. A decreased angle is seen in proclination of incisors and increased in retroclined incisors.Dental parameter

90

Pog Soft tissue analysis

S-line Steiner suggests that in a well balanced face the lips should touch a line extending from soft tissue contour of the chin to the middle of an S formed by lower border of nose

If lips are beyond this line , it indicates protrusive lips and convex profile. and behind the line shows retrusive lips and the patient may have concave. profile

SOFT TISSUE ANALYSIS

STEINERS S-LINEAJO DO-1959

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Mc NAMARA ANALYSIS

Presented by Dr. James Mc Namara in the December 1984 issue of the American Journal of orthodontics.

It divides craniofacial complex into 5 major sections

Maxilla to cranial base Maxilla to mandibleMandible to cranial baseDentition Airway

SOFT TISSUE EVALUATION

NASOLABIAL ANGLEIt is formed by a line tangent to the base of the nose & a line tangent to the upper lip.This angle may be reflection of the dentoalveolar protrusion. MEAN VALUE IS 102 RANGE = 102 8 DEGREES IN BOTH MALE AND FEMALE

CANT OF UPPER LIPBy constructing an angle using a line tangent to the upper lip nd the nasion perpendicular to FH plane. MEAN VALUE IS 14RANGE = MALES 8 8 DEGREES FEMALES 14 8 DEGREES

HARD TISSUE EVALUATION

The distance is measured between NASION PERPENDICULAR- POINT A.

0 mm in the mixed-dentition person and 1 mm in the adult female and the adult male.

MEAN VALUE :- 0 MMRANGE ; MALES 1.1 2.7 MM FEMALES 0.4 2.3 MM

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Maxillary skeletal protrusion, as indicated by the 5 mm distance from point A to the nasion perpendicular.

Maxillary skeletal retrusion, as indicated by the -4 mm distance from point A to the nasion perpendicular.

PROTRUSIVE MAXILLA

RETRUDED MAXILLA

MAXILLA TO MANDIBLEA LINEAR RELATIONSHIP EXISTS BETWEEN EFFECTIVE LENGTH OF MID FACE AND THAT OF THE MANDIBLE.

EFFECTIVE LENGTH OF MAXILLA CONDYLION TO POINT A.MEAN RANGE 91mmMALES 99.8 6.0 MMFEMALES 91 4.3 MM

EFFECTIVE LENGTH OF MANDIBLE CONDYLION TO GNATHION.MEAN RANGE 117 mmMALES 134.3 6.8 MMFEMALES 120.2 5.3 MM

Terms = small (mixed dentition), medium (adult F), large (adult M).

Maxillo-mandibular differential:

it is the difference between the effective mandibular length and effective mid face length. for small sized individuals such as mixed dentition the difference is 20-23mm. In medium sized individuals difference is 26-29mm. In large individuals difference is 29-33mm.

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In small sized person, such as in mixed-dentition effective mid-facial length maxilla :85 mm mandible : 105 to 108 mm. maxillo-mandibular differential : 20 to 23 mm.

In medium-sized person, such as an adult female:effective mid-facial length: 94 mm effective length of the mandible : 120 to 123 mm.Maxillo-mandibular differential: 26 to 29 mm.

In large person, such as an adult male:effective mid-facial length: 100 mm and that of the mandible 130 to 133 mm, with a differential of 30 to 33 mm.

MANDIBLE TO CRANIAL BASE=

POGONION TO NA PERPENDICULAR.

MALES -0.3 +/- 3.8 MMFEMALES -1.8 +/- 4.5 MM

Both point A nd Pog are located on N perpendicular, indicating normal maxilla and mandible.

MEAN VALUE SEVERELY RETRUDED MANDIBLE = -31mm Mildly retrusive maxilla = -3mm

DENTITIONFOR UPPER INCISOR= VERTICAL LINE THROUGH POINT A PARALLEL TO N-PERPENDICULAR. The distance from point A to Facial surface of maxillary incisor. And this value is between 4-6 mm.

FOR LOWER INCISOR = The distance Measured b/w edge of the incisor & line drawn from point A to Pog. This value is 0. Normal : 1 mm to 3 mm

AIRWAY MEASUREMENT

UPPER PHARYNX :MEASURED FROM POSTERIOR PHARYNGEAL WALL TO THE ANT. HALF OF SOFT PALATE.

AVERAGE IS 15 -20 mm IN WIDTH.

2 mm or Less indicate airway impairment.

LOWER PHARYNX :

Lower pharyngeal width is measuredfrom the intersection of the posterior border of the tongue and the inferior border of the mandible to the closest point on the posterior pharyngeal wall. lower pharyngeal width- 22 mm. The average measurement is 11-14mm

Higher value suggests Patient with enlarged tonsils and a forward tongue position.

the effective length of the mid-face will increase approximately 1 to 2 mm per year.

the effective length of the mandible will increase approximately 2 to 3 mm per year.

anterior facial height will increase approximately 1 mm per year.

Cephalometric tracing of ideal 9-year-old. Cephalometric tracing of the same ideal patient 2 years later.

A

RADIATION PROTECTION PRINCIPLES For patients

No radiograph taken unless prescribedALARA (As Low As Reasonably Achievable).Use of high speed films.Use of lead aprons or Thyroid collar.

For radiologistNo person below age of 19 yrs.Operator must stand 6 feet away from X-Ray source.Use of lead shields.Maximum permissible dose -20mSv/year.

Cephalometric basics and errors

Digital Cephalometry and 3D Imaging

DOLPHIN IMAGING PLUSSnap your photos in sequence and Dolphin will automatically arranged the images into a standard layout, such as composite of extraoral, intraoral and occlusal photos.

Preview, crop, rotate, enhance and align photos in a single screen.

Enhancements include brightness, contrast, hue, saturation, and red eye reduction.

Drag and drop images from your file folders into Dolphin.

Option to automatically preserve the original, un-retouched image.

Demonstrate how the patient might look with braces on, with straight teeth, or after completing the procedure.

CLASS I

Normal skeletal and dental & soft tissue profile.

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CLASS II DIV I

Reason of this may be skeletal, dental or in combination.

Excessive overjet .

Vertical growth.(clockwise growth pattern)

Facial type- Dolicofacial.

CLAAS II DIV II

horizontal growth. (Counterclockwise pattern)

deep bite.

Facial type- Brachyfacial.

CLASS III

Negative overjet.

Obtuse gonion angle.(vertical, excessive Mandible growth.

Concave profile.

MAXILLA SNA () 81 3 82 2A-Na Perpendibular (mm) 0 2 1 2Mx. Length : Co-A (mm) 87 6 (m) 99 6 (m) 85 6 (f) 91 4 (f) 9 Year Adult

Maxillary length measured from cd to point A.Pedo patient 85mm

Increases 1 mm per year until the adult size. (95 to 100mm)

Maxillary DepthThe angle formed by the intersection of the FH and N-A plane.

It is 90 3.

It indicates horizontal position of maxilla. Class II skeletal malocclusion caused by prognathic maxilla show more than 90.

Chrnic thumb suckers have also large value.

Maxillary incisor angulationThe angle formed by SN and the INCISOR long axis.

Value is 102 3.

Relates the upper incisor angulation to the upper face. Increase in value shows incisor protrusion.

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BASAL RELATIONSHIP : MAXILLA TO MANDIBLEANB() 9 Year 4 2 2 2 Adult Difference between SNA and SNB

Indicates horizontal relationship between maxilla and mandible.

Positive value indicates maxilaa is forward to mandible.

Negative value class III

MANDIBLESNB () 76 2 80 2Pg-Na Perpendicular (mm) -6 3 -2 2Md. Length : Co-Gn (mm) 117 6 (m) 134 6 (m) 105 6 (f) 120 6 (f)

9 Year Adult

Mandibular incisor protrusionThe horizontal distance between tip of the mandibular incisor to A point-Pog line.It defines the AP position of the mandibular dental unitValue is 2 mm.

FACIAL TYPE/GROWTH PATTERN FMA() 29 5 26 4

This angle formed by the intersection of the FH and MP.It decrease 1 degree every 4 years during normal growth.Value is excess of 31 degree may indicate clockwise growth. Nd value less than 21 degree indicates horizontal growth.

9 Year Adult

Facial HeightThe vertical relationship between upper and lower facial height.For upper facial height = N-ANSFor lower facial height = ANS- MUPPER= 53 mmLOWER = 65 mm

MANDIBULAR DENTITIONIMPA () 95 5 93 5

The inner angle between the long axis of the mandibular incisor and MP.It gives evaluation of the angular position of the incisor to the mandibular basal bone.Value is 90 degree.

9 Year Adult

FACIAL / SOFT TISSUE PROFILE

Upper lip- E line (mm) -1 2 -4 2Lower lip- E line (mm) 0 2 -2 2

9 Year Adult

CONCLUSIONCephalogram is 2D representation of 3D object.

The treatment of skeletal disharmonies presents better results when performed during the growth period. The physical changes that occur in every individual express growth, which is ruled by genetic, general and environmental factors. In order to identify such disharmonies and hence concentrate the clinical actions during treatment and influence facial growth, cephalometrics appears as a useful diagnostic tool for identifying facial growth patterns or growth direction.

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REFERENCES1. AA. Jacobson. Radiographic cephalometry: from basics to 3D imaging .2nd edition.2. Mc Namara JA Jr, Brudon WL. Orthodontics and dentofacial orthopedics. Needham Press. 2nd Ed. 2002.3. ORTHODONTIC CEPHALOMETRY ATHANASIOS E ATHANASIOU4. RADIOGRAPHIC CEPHALOMETRY- ALEXANDER JACOBSON5. CEPHALOMETRIC RADIOGRAPHY THOMAS RAKOSI6. CEPHALOMETRICS FOR ORTHOGNTHIC SURGERY. JOURNAL OF ORAL SURGERY, VOLUME 36.APRIL 1978 - CHARLES J BURNSTONE

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Johnston LE Jr: An objective evaluation of the pitchfork analysis (PFA), EJO 2002 vol 24 page 121- 123. J.A Salzmann. Practice of orthodontics. volume one:538-542Athanasio E Athanasiou: Orthodontic Cephalometry, 1995 pg 269Thomas Rakosi. An atlas and manual of cephalometric radiography.Jarabak and Fizzell. Technique and treatment with light wire edgewise appliances. 2nd edition.Mannchen R. A critical evaluation of pitchforks analysis. Ejo.2001;23(1):1-14.

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