Why does CBCT generally have a higher dose than conventional dental radiographs?

Why does CBCT generally have a higher dose than conventional dental radiographs?

• A. Use of three-dimensional imaging and potentially larger field of view.
• B. Faster processing.
• C. Lower energy photons.
• D. Color imaging.

Answer: (C)

Three-dimensional imaging requires collecting many X-ray projections around the patient to build a full volume. This means more exposure overall, especially when the field of view covers a larger area. Conventional dental radiographs capture one or a few two‑dimensional images, so they use less radiation. The total dose rises with the number of projections and the size of the scanned volume, which is why CBCT exams typically have higher patient doses. Processing speed, color imaging, or using lower energy photons don’t drive the higher dose in the same way; the key factor is the need for 3D data and potentially larger field of view, which increases the amount of tissue irradiated and the total exposure.

Three-dimensional imaging requires collecting many X-ray projections around the patient to build a full volume. This means more exposure overall, especially when the field of view covers a larger area. Conventional dental radiographs capture one or a few two‑dimensional images, so they use less radiation. The total dose rises with the number of projections and the size of the scanned volume, which is why CBCT exams typically have higher patient doses. Processing speed, color imaging, or using lower energy photons don’t drive the higher dose in the same way; the key factor is the need for 3D data and potentially larger field of view, which increases the amount of tissue irradiated and the total exposure.