Air abrasion is a modern technology which allows a dentist to address cavities at their earliest stages as a gentle alternative to a dental drill. Small cavities can be detected with a diagnostic laser and then treated with air abrasion before the cavity becomes large enough to require a larger filling. These restorations are very conservative and rarely require anesthetic to complete the process.
For more information on air abrasion see: http://www.agd.org/consumer/topics/air_abrasion/