Radiology · single question
According to the ALARA principle, what is the BEST radiographic method to diagnose caries in a patient who only has caries visible on X-rays?
Show answer and explanation
Correct answer: A. Bitewing radiographs (BW)
ALARA = As Low As Reasonably Achievable. For caries detection, bitewing radiographs provide the BEST image of interproximal and occlusal caries with the LOWEST radiation dose. They are the standard of care for caries diagnosis. CBCT delivers 10-100x more radiation than a full mouth series and is NOT indicated solely for caries diagnosis. The principle of ALARA dictates using the minimum radiation necessary — BWs accomplish this perfectly for caries.
- A. CORRECT. Bitewing radiographs are the gold standard for caries detection with minimal radiation exposure — perfectly aligned with the ALARA principle.
- B. Incorrect. CBCT delivers significantly higher radiation doses and is NOT indicated for routine caries diagnosis. Using CBCT for simple caries violates ALARA.
- C. Incorrect. Panoramic radiographs provide an overview but have poor resolution for detecting early interproximal caries compared to bitewings.
- D. Incorrect. While a full mouth series provides complete dental information, it delivers more radiation than BWs. For caries-specific diagnosis, BWs suffice and minimize dose.