radiology

Question 1

What are the differences between the frankfort plane and the orbitomeatal line?

Answer 1

FP = lower border of orbit-EAM
OM = outer canthus of eye - EAM
about 10 degrees out

Question 2

What are the indications for taking a lateral skull?

Answer 2

BoS #
AP displacement of facial fracture
skull pathology (Pagets)

Question 3

What view would you take for maxillofacial view - PA or AP?

why?

Answer 3

PA - posterioanterior

(anterior (face) is closer to film, less magnified, low energy photons attenuated before reaching most radiosensitive tissues)

Question 4

what is the difference between an OM 0 and OM30?

Answer 4

patient positioned the same

the angle of the x-ray head to the plat changes

Question 5

list some interactions for OM radiographs

Answer 5

mid 1/3 facial fractures (zygoma, le fort)
coronoid process fractre

but largely being replaced by CBCT

Question 6

When is a PA mandible indicated?

Answer 6

angle, post bosy, ramus of mandible (med/lat displacement)

cysts or tumours

facial deformity

Question 7

what are indications for CBCT?

Answer 7

implant planning
impacted teeth
pathology
orthognathic surgery
hypodontia
CLP
dental abnormalities

Question 8

Midline maxillary radiolucency
well defined
corticated
not associated with apices of 11/21 - PDL space is clear.

what is it?

Answer 8

nasopalatine cyst

Question 9

multiple mandibular radiolucencies in mixed dentition
all assocated with crowns of unerupted teeth. some are deeper, some are superficial.

what are they?

Answer 9

deeper ones are dentigerous cysts and need excision if they delay eruption

superficial ones are eruption cysts and need marsupialisation

Question 10

madibular radiolucency below the IAN canal, what is it?

Answer 10

as below canal cannot be odontogenic in origin

must be stafnes cavvity

Question 11

why is swelling in the palate concerning?

Answer 11

if there is odontogenic pathology of the max teeth, it causes buccal swelling.
palatal can be more sinister and from parotid

Question 12

Pa radiolucency after tooth has had RCT. well defined radiopaque margin. what is it?

Answer 12

periapical granuloma

healing infection from before RCT

Question 13

large, oval distal radiolucency in RHS mandible. 
well defined margin
corticated
salloped
destruction of ID canal

Answer 13

ameloblastoma - destruction suggests aggressive

think odontogenic tumour

Question 14

what is an ameloblastoma like radiographically?

Answer 14

radiolucent
benign
multilocular (uni variant)
30-50ys
will recur if not fully removed
slow growing
locally destructive

Question 15

what is an ameloblastoma like histologically?

Answer 15

infiltrative growth (not expansive)
no fibrous capsule
islands with single layer of columnar epithelium
stellate reticulum

Question 16

if there is a radioluncency around the cron of a tooth, wahat could it be?

Answer 16

dentigerous cyst
adenomatoid odontogenic tumour (ant max, and has patchy calcification)
calcifying epithelial odontogenic tumour (further up tooth than dentigerous cyst, very displaced tooth)

Question 17

how does an odonttogenic myxoma appear?

Answer 17

benign, multilocular soap bubble radiolucency
locally destructive as no capsule
bucco-lingual expansion
gelatinous tissue

Question 18

What are some developmental abnormalities of bone?

Answer 18

• osteogenesis imperfecta
• achondroplasia
• osteopetrosis
• cherubism

Question 19

if a patient presenst with slow growing, asymtomatic bony swelling and precocious puberty - what would you diagnose?

Answer 19

albrights syndrome

Question 20

What are some inflammatory bone diseases?

Answer 20

alveolar osteitis 
osteomyelitis
actinomycosis
periositis
MRONJ
ORNJ

Question 21

What are some giant cell lesions of the jaws and what are some differentials for them?

Answer 21

peripheral giant cell epulis
central giant cell granuloma

differnetial

• osteitis fibrosa cystica
• aneurysmal bone cyst

Question 22

What is the pattern for pagets?

Answer 22

M >40

active increased bone turnover, but burns out

Question 23

What are some different cementum lesions?

Answer 23

cementoblastoma (attached to root)

cemento osseous dysplasias (radiolucency which calcifies)

Question 24

what are you likely to see with a radicular cyst?

Answer 24

commonly sequel to pulpitis/Pa granuloma
well defined radiolucency around apex
continuous with lamina dura
Bx of FNA shows neutrophils, cholestrol clefts,rushton bodies

Question 25

what would you experience with an odontogenic keratocyst?

Answer 25

angle of mand, PA expansion
no clinical symptoms
well defined
thin keratin - no rete pegs
satellite cells in wall
cell nests
contains creamy semi solid material

can be related to gorlin goltz