ceph tracing techniques Flashcards
How are american and european cephs different
american looks to the right
European looks to the left
american magnified (closer x-ray tube)
why trace cephs
eliminate most of detail to focus on areas of important
what is bolton’s template
showed the average proportion at each year of 16 males and 16 females seen to have ideal face proportions
- used as a stanrard
pros of cone beam
produced 3D images
cons of cone beam
too much info and needed to be reduced
how to do the standard cephalometric technique
Puttting patient into a headholder with ear rods
getting the head level
where is the frankfot plane
superior portion of external auditory meatus to inferior margin of the orbit
how ro set up the frankfort plane in a ceph
parallel to the floor
how do we see the natural head
uses a hanging chain to show a true horizontal perpendicular to it
how do we pick landmarks
Identified accurately on a ceph
represent a known part of 1 of the 5 major functional units
what are the landmarks for the cranial base
Sella
Nasion
what does the sella indicate
Postition of the posterior end of the anteior cranial base
- located in the center of the sella turcica
what does the nasion indicate
Front end of the anterior cranial base
- located in the junction b/t nasal and frontal bones
what are the land marks for the maxilla
Anterior nasal spine
Point A
Posterior Nasal spine
what does the anterior nasal spine indicate
Front end of maxilla
what does point a indicate
Innermost point of the contour of the premaxilla between the anterior nasal spine and incisor teeth
what does the posterior nasal spine indicate
Posterior end of the maxilla at the tip of the palatine bone
what are the landmark positions for the mandible
point b Pogonion Menton Gnathion Gonion
where is point b
innermost point of the contour of the mandible betwen the incisor tooth and bony chin
what does point bindicate
anterior part of the bony base of the mandibular dentision
what is pogonion
Most anterio point on the contour of the chin
what is the menton
most inferior point of the mondibular symphysis
what is the gnathion
Center of the inferior contour of the chin (halfway between pogonion and menton)
what is the Gonion
Angle of the mandible
what are the landmarks for max and mandibular dentition
max central incisor tip
Mandibular central insicor tip
max 1st molar, mesial cusp tip
mand 1st molar mesial cust tip
what are the horizontal reference lines
S-N True horizontal ANS-PNS Functional occlusal GO-Gn
what does the S-N line indicate
Anterior cranial base inclinaction
where is the true horizontal found
perpendicular to true verticle
what does the ANS-PNS go
Palatal plane
what is the functional occlusal plane drawn through
Occluding surface of the posterior teeth
what does the Go-Gn plane specifiy
The mandibular plane
