radiographic interpretation Flashcards
what features of a radiograph do we look at to determine if there is a problem
symmetry
margins
bone consistency
dentition
supporting bone
any other features
summary
proposals
if there is a straight opaque margin in a sinus what would it suggest it is
if it is straight would suggest it is probably a liquid
- if it was curved would expect to have something in sinus that was expanding
what does radiolucent mean
loss of previously opaque material
what does radiopaque mean
increased attenuation
if replacing air with anything how does it look on radiograph
will look more radiopaque than it did before = e.g. soft tissue in a sinus
how can you tell the difference between cortical and cancellous bone
more compact in cortical
how does site of pathology in radiographs help us diagnose
if in the alveolar bone it could have dental origin
if in basal bone unlikely to be dental origin unless it has spread and expanded into the basal bone
how would you describe the shape of a pathology
- circular = means something expanding evenly
- unilocular
- multilocular = scalloped margin or internal divisions
- irregular = most concerning
what can the size of radiographic pathology indciate
length of time it has been there
what margins can a radiographic pathology have
well-defined
ill-defined= irregular shapes, worrying
what two categories of well-defined margins are there
corticated
not corticated
what does corticated bone look like radiographically
has a white line around it
what does a corticated margin tell us
that the bone is still remodelling which means it is slow growing = good sign
if pathology has caused displacement of another structure what does that tell us
indicates it is slow growing because the bone has had to remodel around it as it is growing and has had time to re-model
if pathology has caused expansion of other structure what does that tell us
reasonably slow growing as bone needs to remodel
if pathology has caused resorption of other structures what does that tell us
fast growing as body doesn’t have time to make a response with remodelling before bone is resorbed
what is the radiological sieve of diagnosis
same as surgical but also have artefact
- normal
- developmental
- traumatic
- inflammatory
- cystic
- neoplastic
- osteodystrophy
- metabolic/systemic
- idiopathic
- iatrogenic
- foreign body
- artefact
why can well-defined lesions sometimes lose their corticated margin
- if they become infected
what does a cyst look like radiographically
radiolucent
differences between CBCT and normal CT
x-ray beam produced is a cone shape
one big detector used for CBCT, CT has thin rows of detectors
CBCT only goes round pt once
CBCT designed to only show hard tissue
CBCT uses much lower radiation dose
clinical indications for CBCT
- implant planning
- impacted teeth
- pathology
- orthognathiv surgery
- hypodontia
- cleft palate
- dental abnormalities
- Endodontic problems
- autotransplantation
what are basic principles 6, 9, 9 and 10 ofor use of CBCT
6 = use only when questions cannot be answered adequately with a lower dose method
8 = if evaluation of soft tissues is required = if think pt has cancer go straight to CT
9 = use smallest volume compatible with clinical situation
10 = choose resolution compatible with clinical situation
what is the axial view of cBCT
like standing underneath pt
what is coronal view of CBCT
like standing in front of patient
what is sagittal view of CBCT
like standing side on to patient
what is a useful system of examination of radiographs
symmetry
margins
bone consistency
dentition
supporting bone
any other features
summary
proposals
which is bigger a cyst or granuloma
cyst
acronyms for parallax
SLOB = same lingual opposite buccal
PAL = you’re pal(atal) comes with you
2 types of parallax
vertical - OPT and maxillary occlusal
horizontal - 2 periapicals
what could suggest erosive change to teeth on a radiograph
crown more radiolucent in areas
