cephalometric1

Lecture one

Definition: Cephalometric radiography is a standardized method of production of skull radiographs, which are useful in making measurements of the cranium and the orofacial complex. The radiograph thus obtained is called a cephalogram.

Cephalometric radiographs is divided in to: Lateral view. Frontal view. (PA)

Lateral Cephalogram
First introduced in 1931 by: Hofran (Germany) and Broadbent (USA)

Advantages of lateral cephalogram

Assess facial and dento-skeletal relationships as an aid for treatment planningEvaluation of changes due to growthEvaluation of changes due to treatmentCould be useful in detection of pathology in the cervical spine, skull, cranial base, jaws, …etc.

15"
60"
Source Plane
X-ray Source
Patient in Head Positioning Device
Mid-saggital Plane
Film Plane
X-ray Film in Cassette
Cephalostat

Cephalostat

Head position in the cephalostat
Ear rods in the external auditory canals+ fixation at the bridge of the nose and the forehead Frankfort plane: Horizontal OR Natural head position Teeth: In centric occlusion Lips: In habitual position

Cephalometric landmarks

Cephalometric landmarks are divided into: Unilateral landmarks. These landmarks identify structures in the mid-sagittal plane. Bilateral landmarks. These landmarks identify structures in the right & left side of the head.

Sella (S): The midpoint of the sella turcica

Sella
Porion
Gonion
PNS
Menton
Gnathion
Pogonion
ANS
Nasion
Articulare
Unilateral Cephalometric landmarks

Nasion (N): The most anterior point of the frontonasal suture

Sella
Porion
Gonion
PNS
Menton
Gnathion
Pogonion
ANS
Nasion
Articulare
Unilateral Cephalometric landmarks

Anterior nasal spine (ANS): The tip of the anterior nasal spine

Sella
Porion
Gonion
PNS
Menton
Gnathion
Pogonion
ANS
Nasion
Articulare
Unilateral Cephalometric landmarks

Posterior nasal spine (PNS): The tip of the posterior nasal spine

Sella
Porion
Gonion
PNS
Menton
Gnathion
Pogonion
ANS
Nasion
Articulare
Unilateral Cephalometric landmarks


Point A: subspinale The most posterior point on the profile of the maxilla between the anterior nasal spine and the alveolar crest
Sella
Porion
Gonion
PNS
Menton
Gnathion
Pogonion
ANS
Nasion
Articulare
Unilateral Cephalometric landmarks
A
B



Point B: supramentale The most posterior point on the profile of the mandible between the chin point and the alveolar crest
Sella
Porion
Gonion
PNS
Menton
Gnathion
Pogonion
ANS
Nasion
Articulare
Unilateral Cephalometric landmarks
A
B

Pogonion (Pog): The most anterior point of the bony chin

Sella
Porion
Gonion
PNS
Menton
Gnathion
Pogonion
ANS
Nasion
Articulare
Unilateral Cephalometric landmarks

Gnathion (Gn): The most inferior anterior point on the mandibular symphysis in the midline

Sella
Porion
Gonion
PNS
Menton
Gnathion
Pogonion
ANS
Nasion
Articulare
Unilateral Cephalometric landmarks

Menton (Me): The lowermost point of the mandibular symphysis in the midline

Sella
Porion
Gonion
PNS
Menton
Gnathion
Pogonion
ANS
Nasion
Articulare
Unilateral Cephalometric landmarks

Incision superius (IS): The tip of the crown of the most prominent upper central incisor

Sella
Porion
Gonion
PNS
Menton
Gnathion
Pogonion
ANS
Nasion
Articulare
Unilateral Cephalometric landmarks

Incision inferius (II): The tip of the crown of the most prominent lower central incisor

Sella
Porion
Gonion
PNS
Menton
Gnathion
Pogonion
ANS
Nasion
Articulare
Unilateral Cephalometric landmarks



Superior Prosthion (SPr or PR) Also termed supradentale. The most anterior Inferior point on the maxillary alveolar process.
Sella
Porion
Gonion
PNS
Menton
Gnathion
Pogonion
ANS
Nasion
Articulare
Unilateral Cephalometric landmarks

Unilateral Cephalometric landmarks

Sella
Porion
Gonion
PNS
Menton
Gnathion
Pogonion
ANS
Nasion
Articulare
Infradentale (Id) The most anterosuperior point on the mandibular alveolar process.



Basion (Ba) The most infero-posterior point in the sagittal plane on the anterior rim of the foramen magnum (the tip of the posterior cranial base).
Unilateral Cephalometric landmarks

Gonion (Go): The most posterior inferior point on the angle of the mandible

Sella
Porion
Gonion
PNS
Menton
Gnathion
Pogonion
ANS
Nasion
Articulare
Bilateral Cephalometric landmarks

Orbitale (Or): The most inferior anterior point of the orbit

Sella
Porion
Gonion
PNS
Menton
Gnathion
Pogonion
ANS
Nasion
Articulare
Bilateral Cephalometric landmarks

Porion (Po): The uppermost, outermost point on the bony external auditory meatus

Sella
Porion
Gonion
PNS
Menton
Gnathion
Pogonion
ANS
Nasion
Articulare
Bilateral Cephalometric landmarks


Articulare (Ar) The intersection of the posterior border of the neck of the condyle and the lower margin of the posterior cranial base
Sella
Porion
Gonion
PNS
Menton
Gnathion
Pogonion
ANS
Nasion
Articulare
Bilateral Cephalometric landmarks



Pterygomaxillary Fissure (Ptm) A bilateral teardrop-shaped area of radiolucency, the anterior shadow of which is the posterior surfaces of the tuberosities of the maxilla.
Bilateral Cephalometric landmarks
Sella
Porion
Gonion
PNS
Menton
Gnathion
Pogonion
ANS
Nasion
Articulare

Bolton Point (BO) The highest point in the upward curvature of the retrocondylar fossa.

Bilateral Cephalometric landmarks