Radiography and Imaging
Core Concepts
Radiography is integral to diagnosis and treatment planning. Candidates must understand radiation physics, image formation, and interpretation. Key concepts include intraoral (periapical, bitewing, occlusal) and extraoral (panoramic, CBCT) imaging, indications, and limitations. Also, knowledge of radiation safety (ALARA principle, shielding, collimation) and quality assurance is essential.
Common Traps
Questions often test the choice of imaging modality: bitewings for interproximal caries, periapicals for periapical pathology, panoramic for overview, CBCT for 3D assessment. Another trap is the interpretation of common radiolucencies and radiopacities. Also, be clear on the risks of radiation and the importance of justification and optimization.
Worked Example / Rule of Thumb
A patient with suspected impacted third molar requires a panoramic radiograph to assess position and relation to adjacent structures. If further detail is needed, CBCT may be indicated. Rule of thumb: always use the lowest radiation dose that provides the necessary diagnostic information (ALARA).