Air abrasion is defined as bombardment of the tooth surface with high velocity particles of which material carried in a stream of high pressure air?

• A. Bombarding with high velocity aluminum oxide particles carried in a stream of high pressure air
• B. Using diamond particles and laser pulses
• C. Hydrogen peroxide and heat
• D. Cryogenic nitrogen jet blasting

Answer: (A)

Air abrasion removes tooth structure by blasting the surface with tiny abrasive particles carried in a stream of high‑pressure air. The material used for these particles is aluminum oxide. Aluminum oxide is chosen because it is very hard and inert, and it can be manufactured into small, uniform particles that effectively abrade enamel and dentin with minimal heat generation or damage to adjacent tissues. The other options involve different technologies or chemicals (diamond particles with lasers, hydrogen peroxide with heat, or cryogenic nitrogen jets) and do not describe the air‑abrasion mechanism.