Principles of Radiographic Differential Dx

Question 1

What is radiolucent?

Answer 1

Allows the passage of x-rays. Appears black. Destruction of bone.

Question 2

What is radiopaque?

Answer 2

Blocks the passage of x-rays. Appears white. Formation of bone or other mineralized material.

Question 3

What are the DD options for a periapical lucency?

Answer 3

– Periapical abscess
– Periapical Granuloma/Cyst/Scar
– Odontogenic Keratocyst (OKC)
– Early Periapical/Focal Cemento-Osseous Dysplasia (BFOLs)
– Ameloblastoma
– Nasopalatine duct cyst/Median palatal cyst
– Artifact- Mental foramen, nasal foramen
– Dentin dysplasia-Type1
– Vitamin D resistant rickets (hypophosphatemia)

Question 4

What are the DD options for a pericoronal unilocular radiolucency in an adult?

Answer 4

– Hyperplastic Follicle
– Dentigerous Cyst
– OKC (small, early)
– Ameloblastoma (unicystic)

Question 5

What are the DD options for a “floating teeth”?

Answer 5

• Langerhans Cell Histiocytosis – scooped out radiolucency
• Burkitt Lymphoma
• Melanotic neuroectodermal tumor of infancy
• Leukemia– especially if destroying follicle

Question 6

What is ALWAYS an ominous sign?

Answer 6

“floating teeth”