Air abrasion (sandblasting) involves cleaning the tooth surface with 27 micron or 50 micron alumna oxide particles. Air abrasion units are an essential component of adhesive dentistry. Sandblasting can be used as an adjunct for composite restorations and for bonding adhesively retained restorations, such as lithium disilicate onlays (e-Max). As explained by Van Meerbeek et al 2003, sandblasting significantly improves the bond strength with self etching adhesives to dentine. When placing composites, prior to etching, treating the tooth surface with air abrasion helps remove the surface pellicle layer and creates a clean and optimal surface ready for bonding. The pictures below, show the difference in appearance before and after air abrading the teeth.
Sandblaster
Onlay prep before sandblasting
Tooth after sandblasting
Onlay fit