NBDE Oral Pathology and Radiology 2 — Questions and Answers
Question 1: A radiolucent lesion with a 'soap bubble' multilocular appearance at the posterior mandible in a young adult is most consistent with:
- Dentigerous cyst
- Ameloblastoma (Correct answer)
- Odontogenic keratocyst
- Central giant cell granuloma
Correct answer: Ameloblastoma
Ameloblastoma classically presents as a multilocular 'soap bubble' or 'honeycomb' radiolucency, most often in the posterior mandible of adults.
Question 2: Koilocytes found on cytologic smear are pathognomonic for infection with:
- Herpes simplex virus
- Candida albicans
- Human papillomavirus (Correct answer)
- Epstein-Barr virus
Correct answer: Human papillomavirus
Koilocytes are HPV-infected epithelial cells showing perinuclear clearing (halo) and nuclear enlargement, serving as a hallmark of HPV infection.
Question 3: On a periapical radiograph, the lamina dura appears as a thin radiopaque line because it represents:
- Cortical bone lining the alveolar socket (Correct answer)
- The periodontal ligament space
- Cementum covering the root surface
- Cancellous trabeculae adjacent to the tooth
Correct answer: Cortical bone lining the alveolar socket
The lamina dura is dense cortical bone lining the tooth socket, appearing radiopaque due to its compact nature compared to surrounding cancellous bone.
Question 4: Pindborg tumor (calcifying epithelial odontogenic tumor) characteristically shows which radiographic feature?
- Pure radiolucency with sclerotic border
- Diffuse 'driven snow' calcifications within a radiolucency (Correct answer)
- Sunburst periosteal reaction
- Well-corticated unilocular radiolucency
Correct answer: Diffuse 'driven snow' calcifications within a radiolucency
CEOT (Pindborg tumor) contains amyloid-like material that calcifies, producing scattered 'driven snow' or 'snowflake' opacities within a radiolucent lesion.
Question 5: A patient presents with multiple radiopaque masses along the jaw resembling condensed bone fused to tooth roots. This most likely represents:
- Florid cemento-osseous dysplasia (Correct answer)
- Osteosarcoma
- Gardner syndrome osteomas
- Periapical cemento-osseous dysplasia
Correct answer: Florid cemento-osseous dysplasia
Florid cemento-osseous dysplasia presents as multiple bilateral, large lobular cemento-osseous masses replacing normal bone, predominantly in Black women.
Question 6: Erythroplakia of the oral mucosa carries a higher risk of malignant transformation than leukoplakia because:
- It contains more keratin
- It has a higher rate of severe dysplasia or carcinoma in situ at biopsy (Correct answer)
- It is always caused by Candida
- It occurs only on non-keratinized mucosa
Correct answer: It has a higher rate of severe dysplasia or carcinoma in situ at biopsy
Erythroplakia shows severe dysplasia, carcinoma in situ, or invasive carcinoma in up to 90% of biopsied cases, far exceeding the malignant potential of leukoplakia.
Question 7: A panoramic radiograph reveals 'step-ladder' trabecular pattern of the mandible. This pattern is associated with:
- Paget disease of bone
- Sickle cell anemia (Correct answer)
- Osteoporosis
- Hyperparathyroidism
Correct answer: Sickle cell anemia
Sickle cell anemia causes a 'step-ladder' trabecular pattern on panoramic radiographs due to marrow hyperplasia enlarging medullary spaces between horizontal trabeculae.
NBDE Oral Pathology and Radiology 2
A radiolucent lesion with a 'soap bubble' multilocular appearance at the posterior mandible in a young adult is most consistent with: