(2) A multilocular radiolucency

Question 1

Is a slow-growing lesion (e.g. over 6 months) likely to be benign or malignant?

Answer 1

Benign

Question 2

What are the three most common odontogenic cysts?

Answer 2

• Radicular cyst
• Dentigerous cyst
  
  • Unerupted teeth
• Odontogenic keratocyst

Question 3

Which radiograph views are indicated?

Answer 3

• Panoramic radiograph/oblique lateral
• Posterior-anterior of the jaws
  
  • Extent of mediolateral expansion of the posterior body, angle, or ramus
• Lower true (90 deg) occlusal
  
  • Lingual expansion
• PA of teeth in region of the lesion
  
  • Assess bone support
  • Possible root resorption

Question 4

Why may there be differences in root length between two radiographs?

Answer 4

• Foreshortening/elongation of tooth due to receptor placement

Question 5

Parameters for features of lesion

Answer 5

• Site
• Size
• Shape
• Outline/edge
• Relative radiodensity
• Effects on adjacent structures

Question 6

What are features of ameloblastoma?

Answer 6

• Expanding multilocular radiolucency at angle of mandible (classic)
• Common in African racial group
• Cystic spaces separated by bony septa
• Root resorption
• Tooth displacement
• Marked expansion

Question 7

What are features of giant cell granuloma?

Answer 7

• Expansion and a honeycomb/multilocular radiolucency
• No root resorption
• Solid tissue (not cystic neoplasm)
• Wispy osteoid or fine bone septa
• Honeycomb-like pattern

Question 8

Is a biopsy required? If so, what precautions must be taken?

Answer 8

• Yes
• Obtain sample of solid lesion
  
  • Cyst lining not always sufficiently characterstic histologically to make diagnosis

Question 9

What other imaging investigations would be appropriate? Describe their purpose.

Answer 9

• CBCT (cone beam computed tomography)
  
  • Show extent of the lesion in bone
• MRI (magnetic resonance imaging)
  
  • Show surrounding soft tissue