What is the primary X-ray production mechanism in dental X-ray tubes?

• A. Bremsstrahlung radiation
• B. Characteristic radiation from tungsten
• C. Compton scattering
• D. Pair production

Answer: (A)

When the high-speed electrons slam into the heavy tungsten target, they are constantly deflected and slowed by the strong electric field of the nuclei. That rapid deceleration causes the electrons to emit photons, producing X-rays through Bremsstrahlung radiation. This deceleration-based emission creates a broad, continuous spectrum of X-ray energies, which is the dominant source in dental X-ray tubes.

There is also a separate process where electrons eject inner-shell electrons and the atom relaxes by emitting characteristic line radiation. That component exists but is a smaller portion of the total X-ray output in dental systems. Pair production requires energies well above typical dental tube voltages and is not a practical mechanism here, and Compton scattering describes photon interactions after emission rather than how the photons are produced.