From Pro/Help 2001:
About Pro/SCAN-TOOLS Capabilities
Pro/SCAN-TOOLS provides you with a set of tools to transform imported surfaces, quilts, triangulation data, or raw data into manufacturable models.
Pro/SCAN-TOOLS lets you perform the following tasks:
Import, generate, and filter raw data
Import geometry, including curves, surfaces, and faceted data
Create and modify curves
Heal geometry manually or automatically (with a license for only DataDoctor)
Collapse geometry from later features into the Style feature (with a license for DataDoctor)
Note: When you redefine an Import feature in the Pro/SCAN-TOOLS environment, you can use Pro/SCAN-TOOLS functionality in addition to the standard Redefine Import tools.
Recommended Usage
While the Style application is the recommended environment for parametric styling operations, Pro/SCAN-TOOLS is recommended when creating shapes from nonparametric data (raw data and imported geometry).
Pro/SCAN-TOOLS Objects
In Pro/SCAN-TOOLS you work with quilts, surfaces, curves, and raw data. You can modify only a limited set of non-analytical geometry. You can also use Pro/SCAN-TOOLS to copy and convert any existing curve or surface into a modifiable entity. For example, to be able to modify a cylinder, you must first convert it into a spline surface by using Geometry > Surface > From Surface.
If you have a license for DataDoctor, you can bring old Pro/SCAN-TOOLS objects, such as curves and surfaces, into the Pro/SCAN-TOOLS geometry by collapsing them.
Hope this helps