Cephalometric Landmarks

Anterior Nasal Spine

(ANS) • The most anterior point on the maxilla at the level of the palate. • The anterior tip of the sharp bony process of the maxilla at the lower margin of the anterior nasal opening.

Articulare

(Ar) • A point at the junction of the posterior border of the ramus and the inferior border of the posterior cranial base (occipital bone).

Basion

(Ba) • Point at the center of the *anterior border of the foramen magnum* at the base of the occipital bone.

Condylion

(Cd) The most superior point on the mandibular condylar head.

Soft -Tissue Landmarks Soft Tissue Glabella

(G) Most anterior point in the midsagittal plane of the forehead at the level of the superior orbital ridges.

Glabella

(Gl) • The most anterior point of the frontal bone.

Gnathion

(Gn) • The most anterior inferior point in the lateral shadow of the chin. • Ganthion usually is best determined by selecting the midpoint between pogonion and menton on the contour of the chin.

Soft tissue Gnathion

(Gns) Midpoint between the most anterior and inferior points of the soft tissue chin in the midsagittal plane.

Gonion

(Go) • A point on the curvature of the angle of the mandible located by bisecting the angle formed by lines tangent to the posterior ramus and the inferior border of the mandible.

Insision inferius Apicalis

(Iia) • The root apex of the most anterior mandibular central incisor.

Incision inferius Incisalis

(Iii) • Incisal edge of the most prominent/ labial mandibular central incisor.

Incision Superius Apicalis

(Isa) UIA The upper incisor apex is the root apex of the most prominenet upper incisor.

Incision Superius Incisalis

(Isi) • The incisal tip of the most anterior maxillary central incisor.

Lower Incisor

(L1) 1.Incision inferius Incisalis (Iii) 2.Insision inferius Apicalis (Iia)

Mandibular 1st Molar

(L6) The tip of the mesiobuccal cusp of the mandibular first permanent molar.

Labrale Inferius

(Li) Most anterior point on the lower margin of the lower membrane lip.

Labrale Superius

(Ls) Most anterior point on the upper margin of the upper membrane lip.

Menton

(Me) • The lowest point on the symphyseal shadow of the mandible.

Nasion

(N) • The most Anterior point of the Frontonasal suture in the mid-saggital plane.

Orbitale

(Or) • Lowest point in the inferior margin of the orbit. • midpoint between right and left image.

Posterior Nasal Spine

(PNS) • Midpoint of the base of the palatine bone at the posterior margin of the hard palate.

Pterygomaxillary Fissure

(PTM) • Bilateral tear-drop shaped area, the anterior shadow of which represents the posterior surface of the tuberosity of the maxilla.

Pronasale

(Pn) The most prominent or anterior point of the nose.

Porion

(Po) • The most superiorly positioned point of the external auditory meatus • Sometimes located by using the ear-rods of the cephalostat (Machine Porion)

Soft tissue Pogonion

(Pog) Most prominent or anterior point on the soft tissue chin in the midsagittal plane.

Pogonion

(Pog) • The most anterior point on the bony chin.

Prosthion

(Pr) Lower most anterior point of alveolar process of pre-maxilla in the midline between two maxillary central incisors. The most anterior inferior point on the maxillary alveolar process usually found near the CEJ of the maxillary central incisor.

Sub-nasale

(Sn) The point at which the nasal septum merges with the upper lip in the midsagittal plane.

Soft tissue Sub-mentale

(Soft tissue B point) Point of greatest concavity in the midline of the lip between labrale inferius and soft tissue pogonion.

Stomion

(Sto) Median point of the oral embrasure when the lips are closed.

Maxillary Central Incisor:

(U1) The most labial point on the crown of the maxillary central incisor.

Maxillary 1st Molar

(U6) The tip of the mesiobuccal cusp of the maxillary first permanent molar.

Soft tissue Nasion

(n) Most retruded point in the tissue overlying the area of the frontonasal suture.

Sella

- S Midpoint of sella turcica or hypophyseal fossa or pituitary fossa.

The standardized nature of these projections can help to

1.Establish population norms. 2.Measure and evaluate each case by norms. 3.Compare norms to previous projections. 4.Evaluate Anterior-posterior projections.

The cephalostats x-ray apparatus has a standard ______ source-object distance.

5-foot

A point

Sub-spinale • Deepest point on the curved bony outline between the ANS and Prosthion (Pr). • Deepest point on the curve of the bone between the ANS and dental alveolus.

Point B

Supra-mental • The most posterior point of the bony curvature of the mandible below infra-dentale and above Pogonion.

Cephalometric

___________is the study of head-films, called cephalogram.

A ________ is a *two-dimensional* projection of the skull.

cephalogram

Cephalograms films are taken in a ___________

cephalostat

In cephalometric radiography, the patient is placed with the _____ (right/left) side toward the image receptor.

left

In a cephalostat, the image receptor is positioned parallel to the patient's ________ plane.

midsagittal plane.

Most of the important elements in cephalometric analyses rely on

the relatively stable elements in the *cranial base* to serve as reference points and plans. **No certain analysis is considered superior to another.

A wedge filter at the tube head is positioned over the anterior aspect of the beam to absorb some of the radiation and allow ____________ of the face.

visualization of soft tissues

Superimposition

• Accurate tracings may also be superimposed on subsequent or previous films to *reveal growth* or *treatment changes*. Important elements in cephalometric analysis are • Maxillary position. • Mandibular position. • Facial proportions/vertical relationships. • Incisor positions. (maxillary and mandibular)

We study Ceph to

• Evaluate dentofacial proportions. • Clarify the anatomic basis of diagnosis of malocclusion. • Evaluate changes before, during, and after treatment. • Predict future changes. • Observe pathologic change.

Name the various cephalometric analyses exist to describe the craniofacial complex

• Rickets. • Sassouni. • Tweed. • Mc Namara.

Performing a ceph analysis requires you to

• Trace the film onto a piece of frosted *acetate paper* with a pencil. • *Capture* necessary details in the cranial base, maxilla, mandible, dentition, and soft tissue. • *Measure* the various elements. • *Compare* the measurement with norms.