This folder contains the stereolithography (STL) files of micro-CT scans required to 3D print illustrative models for a new suggested classification system for complex root canal configurations. Each STL file represents a configuration type within a group. The system consists of 12 basic categories or groups (A-D) each with 3 types (1-3). The folder also contains the STL files for rare types of root and canal morphologies: a C-shaped root canal system found in a maxillary first molar and a radix entomolaris tooth found on a mandibular first molar.