radiograph

A radiograph is an image produced by radiography, a medical, dental, or industrial imaging technique that uses ionizing radiation to visualize internal structures. The radiograph is created when radiation passes through an object and is captured by a detector such as photographic film or a digital sensor. Areas that strongly attenuate the radiation, such as dense bone, appear lighter on the image, while less attenuating areas like soft tissue or air appear darker. Radiographs are two-dimensional projections of three-dimensional structures, and their interpretation relies on patterns of attenuation and relative contrast.

In medicine and dentistry, radiography is a fundamental diagnostic tool. Common medical applications include chest radiography to assess the lungs and heart, and radiographs of the limbs, skull, or abdomen. Dental radiography, including bite-wing and panoramic techniques, helps evaluate teeth and supporting structures. In industry, radiography is used for non-destructive testing of welds, castings, and complex components to detect internal defects.

Digital radiography has largely supplanted traditional film in many settings, using flat-panel detectors or computed radiography plates to acquire images that can be processed, stored, and transmitted more efficiently. Safety considerations are central to radiography; exposure to ionizing radiation is minimized through justification of exams, shielding, and dose optimization, following the ALARA principle.

Historically, radiographs date to 1895 with Wilhelm Röntgen’s discovery of X-rays, leading to rapid adoption in medical diagnostics and beyond.