Cephalometry Flashcards
What is sella (S)?
- Craniofacial reference point
* The mid-point of the cavity of sella turcica
Craniofacial reference points for cephalometric analysis include…
- Sella (S)
- Nasion (N)
- Porion (Po)
- Orbitale (Or)
What is nasion (N)?
- Craniofacial reference point
* Anterior point of the intersection between the nasal and frontal bones
What is porion (Po)?
- Craniofacial reference point
- Midpoint of the upper contour of the external auditory canal (anatomic porion)
- Or, midpoint of the upper contour of the metal ear rod of the cephalometer (machine portion)
What is orbitale (Or)?
- Craniofacial reference point
* Lowest point on the inferior margin of the orbit
Maxillary reference points for cephalometric analysis includes…
- Anterior nasal spine (ANS)
- Posterior nasal spine (PNS)
- Point (A)
- Incision superius (Is)
- Apex superius (As)
What is anterior nasal spine (ANS)?
- Maxillary reference point
* The tip of the anterior nasal spine
What is the posterior nasal spine (PNS)?
- Maxillary reference point
* Tip of the posterior spine of the palatine bone, at the junction of the hard and soft palates
What is point A?
- Maxillary reference point
* Innermost point on the contour of the premaxilla between anterior nasal spine and the incisor tooth
What is the incision superius (Is)?
- Maxillary reference point
* Incisal edge of the maxillary incisor
What is the apex superius (As)?
- Maxillary reference point
* Root tip of maxillary central incisor
Mandibular reference points for cephalometric analysis includes…
- Gonion (Go)
- Pogonion (Pog)
- Gnathion (Gn)
- Menton (Me)
- B (point)
- Incision inferius (Ii)
- Apex inferius (Ai)
What is gonion (Go)?
- Mandibular reference point
* Midpoint of the contour connecting the ramus and body of the mandible
What is pogonion (Pog)?
- Mandibular reference point
* Most anterior point on the contour of the chin
What is gnathion (Gn)?
- Mandibular reference point
* Center of the inferior point on the mandibular symphysis (i.e. the bottom of the chin)
What is menton (Me)?
- Mandibular reference point
* The most inferior point on the mandibular symphysis (i.e. the bottom of the chin)
What is point B?
- Mandibular reference point
* Innermost point on the contour of the mandible between the incisor tooth and the bony chin
What is the incision inferius (Ii)?
- Mandibular reference point
* Incisal edge of the mandibular incisor
What is the apex inferius (Ai)?
- Mandibular reference point
* Root tip of mandibular central incisor
Soft tissue reference points for cephalometric analysis includes…
- Pronasale (Pn)
- Labrale inferior (Li)
- Labrale superior (Ls)
- Sabnasale (Sn)
- Chin (soft)
What is the pronasale (Pn)?
- Soft tissue reference point
* Most forward point of the tip of the nose
What is the labrale inferior (Li)?
- Soft tissue reference point
* Most forward point of the lower lip
What is the labrale superior (Ls)?
- Soft tissue reference point
* Most forward point of the upper lip
What is the sabnasale (Sn)?
- Soft tissue reference point
* Bottom point of nose (on the curve from upper lip to nose)
What is the chin (soft)?
- Soft tissue reference point
* Most forward point of the soft tissue chin
Define: a standardized technique of studying the skull by means of laterally oriented head radiographs. It uses living individuals.
Cephalometry
Goals for cephalometric analysis include…
- Orthodontic and orthognathic diagnosis and treatment planning
- Orthodontic treatment outcomes evaluation
- Study and monitor the growth of dentofacial structures
- Functional study of jaw movement
Cephalometric analysis steps…
- Take cephalometric x-ray film + tracing paper
- Cephalometric film tracing (hard vs. soft tissues)
- Determine reference points and planes
- Measure various variables (angular vs. linear)
- Compare the measures with norms –> diagnosis
The cephalometric equipment consists of…
- Cephalostat (head holder)
* X-ray source