Many dentists use air-driven handpieces (the dental term for dental “drills”). While acceptable for many procedures, these “whiney sounding” air-powered handpieces all have a degree of non-concentricity: they do not rotate perfectly smoothly.
For the most precise aspects of restorative procedures, we use electric handpieces. This results in extraordinarily precise interfaces between your tooth and your new restoration (crown, veneer or filling). This will bring more comfort to you as well. With a more precise tool, there is less vibration and less noise.