radiology of multilocular lesions

Question 1

which type of lesions are commonly multilocular?

Answer 1

• odontogenic cysts
• odontogenic tumours
• giant cell lesions
• bone cysts

Question 2

name specific odontogenic cysts

what age group do they occur in?

where do they usually occur?

Answer 2

• odontogenic keratocyst
  
  • adults
  • posterior mandible
• botryoid odontogenic cyst
  
  • adults
  • mandibular canine / premolar region & anterior maxilla (lateral aspect of tooth)

Question 3

name specific odontogenic tumours

what age group do they occur in?

where do they usually occur?

Answer 3

• ameloblastoma
  
  • adults
  • posterior mandible
• odontogenic myxoma
  
  • young adults
  • posterior mandible
• ameloblastic fibroma
  
  • children
  • posterior mandible
• calcifying epithelial odontogenic tumour
  
  • adult
  • posterior mandible

Question 4

name specific giant cell lesions

what age group do they occur in?

where do they usually occur?

Answer 4

• central giant cell granuloma
  
  • adolescents
  • anterior mandible
• cherubism
  
  • children
  • posterior jaws, bilateral
• brown tumour of hyperparathyroidism
  
  • primarily adults
  • anywhere
  • also there are generalised bone changes

Question 5

name specific bone cysts

what age group do they occur in?

where do they usually occur?

Answer 5

• aneurysmal bone cyst
  
  • adolescents
  • posterior mandible

Question 6

describe the radiographic appearance of cysts

• margin appearance
• teeth displaced
• teeth resorbed
• effect on the cortex

Answer 6

• margins
  
  • well defined , corticated
• teeth displaced
  
  • yes
    
    • odontogenic keratocyst is an exception
• teeth resorbed
  
  • no
• effect on cortex
  
  • expansion
    
    • odontogenic keratocyst is an exception

Question 7

describe the radiographic appearance of giant cell lesions

• margin appearance
• teeth displaced
• teeth resorbed
• effect on the cortex

Answer 7

• margin appearance
  
  • well defined, corticated
• teeth displaced
  
  • yes
• teeth resorbed
  
  • no
• effect on the cortex
  
  • expansion

Question 8

describe the radiographic appearance of odontogenic tumours

• margin appearance
• teeth displaced
• teeth resorbed
• effect on the cortex

Answer 8

• margin appearance
  
  • well defined , corticated
• teeth displaced
  
  • yes
• teeth resorbed
  
  • yes
• effect on the cortex
  
  • expansion

Question 9

describe the radiographic appearance of malignancy

• margin appearance
• teeth displaced
• teeth resorbed
• effect on the cortex

Answer 9

• margin appearance
  
  • ill defined
  • ‘moth eaten’
• teeth displaced
  
  • variable
• teeth resorbed
  
  • variable
• effect on the cortex
  
  • destruction

Question 10

what is this lesion most likely to be?

how do you know that?

Answer 10

odontogenic tumour

• multilocular lesion
• corticated margins
• not sure if teeth are displaced
• first molar is resorbed
• expansion of the jaw

Question 11

what is this lesion most likely to be?

how do you know that?

this shows an adult patient

Answer 11

ameloblastoma

• multilocular
• corticated margins
• teeth displaced
• teeth resorbed
• expansion
• therefore an odontogenic tumour in an adult patient = most likely ameloblastoma

Question 12

what is this lesion most likely to be?

how do you know that?

Answer 12

ameloblastic fibroma

• lesion in the upper right maxilla
• multilocular
• well defined margins
• displacement of teeth
• teeth resorbed
• expansion
• odontogenic tumour in a child patient = most likely ameloblastic fibroma

Question 13

how can ameloblastoma and odontogenic myxoma be differentiated from each other?

Answer 13

both have very similar features

• odontogenic myxoma septi between the multilocular are usually in right angles to each other in straight lines
• ameloblastoma septi look more ‘soap bubble like’

Question 14

what is this lesion most likely to be?

how do you know that?

this shows an young adult patient

Answer 14

include both ameloblastoma and odontogenic myxoma in the diagnosis

• multilocular lesion
• well defined margins
• expansion on the lower border of the mandible
• resorption of first molar
  
  • = odontogenic tumour
• most likely odontogenic myxoma due to straight septi

Question 15

what is this lesion most likely to be?

how do you know that?

child patient

Answer 15

central giant cell granuloma

• multilocular
• well defined margins
• displacement
• no resorption
• expansion
  
  • = giant cell lesion
    
    • a child patient with lesion in anterior parts of the jaw
    • = most likely central gian cell granuloma

Question 16

what is this lesion most likely to be?

how do you know that?

child patient

Answer 16

cherubism

• multilocular
• displacement
• no resorption
• expansion
  
  • = giant cell lesion
    
    • in a child patient in posterior parts of jaw - also bilateral
    • = most likely cherubism

Question 17

how can brown tumours of hyperparathyroidism be identified on a radiograph?

Answer 17

• multilocular
• displacement of teeth
• no resorption
• expansion
  
  • = giant cell lesion
• granular appearance of bone
• loss of lamina dura around teeth