Particle size determines cutting efficiency, surface roughness, and precision.
Typical ranges for dental or industrial air abrasion:
25–27 μm – fine, for delicate enamel prep and minimal tissue removal
50 μm – medium, most commonly used for general prep
75–110 μm – coarse, for fast cutting or tough surfaces
Fine particles are smoother but slower; coarse particles are aggressive but roughen surfaces.
2. Purity
High purity is preferred to prevent contamination and ensure consistent abrasion:
≥99% Al₂O₃ for dental/medical applications
Industrial applications may tolerate slightly lower purity (95–98%)
3. Shape
Angular or irregular shapes – produce more aggressive cutting
Rounded particles – smoother, less cutting, used when gentler abrasion is needed
4. Hardness
Mohs hardness: ~9 (just below diamond)
High hardness makes it effective at cutting, cleaning, or etching surfaces like enamel, ceramics, metals, or composites.
5. Moisture Content
Must be dry and free-flowing; moisture can clog nozzles and reduce efficiency.
Often packaged with desiccants or vacuum-sealed.
6. Application Pressure / Settings
Air pressure settings depend on particle size and material:
25–50 μm: 40–60 psi (2.8–4.1 bar) for delicate enamel
50–110 μm: 60–90 psi (4.1–6.2 bar) for faster cutting
Always follow manufacturer specs; too high pressure can damage surfaces or pulp tissue in dental applications.
7. Safety Considerations
Use proper PPE: mask, eye protection, and suction.
Avoid inhalation of fine particles.
Ensure air abrasion units have HEPA or microfiltration to capture residual Al₂O₃.
