Extra Oral Radiography Flashcards
what does extra oral radiography allow for
visualisation of teeth, jaws and facial bones
what are the purposes of extra oral radiography
imaging larger sections of dentition
alternative when patient unable to tolerate intra orals
imaging non-dentoalveolar regions
what are the common types of extra oral radiographs
panoramic
cephalometric
oblique lateral radiographs
skull radiographs
what is cephalometry
measurement and study of the head
what are the clinical applications of cephalometry
orthodontics and orthognathic surgery
monitor changes over time
what must cephalograms be
standardised and reproducible
what are the two types of cephalograms
lateral and postero-anterior
what does a lateral ceph look at
teeth, facial bones and soft tissues
paranasal sinuses
pharyngeal soft tissue
cervical vertebrae
what are lateral cephs used for in orthodontics
assessing skeletal discrepancy
aiding location and assessment of unerupted, malformed or misplaced teeth
giving an indication of upper incisor root length
when are lateral cephs used in orthodontics
diagnosis
treatment planning
monitoring progress
appraisal of treatment results
what do all cephalogram units have
cephalostat
what does a cephalostat ensure
standardised positioning of equipment and patients head
what are the functions of the cephalostat
holds head at correct angle, stabilises head to prevent movement, establishes correct distances between x-ray focal spot and patient and receptor
how far away from the focal spot should the receptor be
1.5 to 1.8m
what is the problem with soft tissues on cephs
they show up poorly when exposure settings are optimised for hard tissues
