Dental materials and radiology basics: thalassaemia skull radiograph: practice question

A Dentistry question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

Try it

Dentistry · Dental materials and radiology basics: thalassaemia skull radiograph

Sample item

A child with chronic severe haemolytic anaemia has a skull radiograph with vertical trabeculae like hair standing on end. What is the mechanism?

AFibro-osseous tissue replacing the medullary cavityBFailure of osteoclast function causing dense marrow-free boneCMarrow hyperplasia that widens the diploe and thins the outer tableDSubperiosteal new bone laid down at right angles to the cortex by a tumour

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

C. Marrow hyperplasia that widens the diploe and thins the outer table

In thalassaemia and other chronic haemolytic anaemias, expansion of the erythroid marrow widens the diploic space and thins the outer table, giving the hair-on-end appearance. Jaw changes include enlarged marrow spaces, a coarse trabecular pattern and maxillary overgrowth.

Option by option

A. Fibro-osseous tissue replacing the medullary cavity
Fibro-osseous replacement is seen in fibrous dysplasia, with ground-glass bone.
B. Failure of osteoclast function causing dense marrow-free bone
Defective osteoclast function causes osteopetrosis, which gives dense sclerotic bones.
C. Marrow hyperplasia that widens the diploe and thins the outer table (correct)
Correct. Expanded marrow thickens the diploe and pushes up radiating trabeculae.
D. Subperiosteal new bone laid down at right angles to the cortex by a tumour
Radiating new bone from a tumour describes the sunray pattern of osteosarcoma.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

Questions about this Dentistry question

What is the answer to this Dentistry question?

The best answer is C, Marrow hyperplasia that widens the diploe and thins the outer table. In thalassaemia and other chronic haemolytic anaemias, expansion of the erythroid marrow widens the diploic space and thins the outer table, giving the hair-on-end appearance.

Why is "Fibro-osseous tissue replacing the medullary cavity" not the answer?

Fibro-osseous replacement is seen in fibrous dysplasia, with ground-glass bone.

Why is "Failure of osteoclast function causing dense marrow-free bone" not the answer?

Defective osteoclast function causes osteopetrosis, which gives dense sclerotic bones.

Why is "Subperiosteal new bone laid down at right angles to the cortex by a t…" not the answer?

Radiating new bone from a tumour describes the sunray pattern of osteosarcoma.

What concept does this question test?

It tests Dental materials and radiology basics: thalassaemia skull radiograph in Dentistry. Jaw changes include enlarged marrow spaces, a coarse trabecular pattern and maxillary overgrowth.

How hard is this question?

We tag it as an application question: it asks you to use a fact on a patient or a finding. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Dental materials and radiology basics: thalassaemia skull radiograph?

Learn the dental formula, eruption ages and tooth structure once, as tables. Then use the flashcards and the other Dentistry questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.