A process for creating a dental model to avoid periodontal defects during planned dental work includes obtaining CT scan data and optical scan data of a patients dentition and integrating the CT scan data and the optical scan data by at least one of surface to surface registration, registration of radiographic markers, and registration of optical markers of known dimensions, to produce a dental model that includes the dentition and underlying bone and root structures. The process then segments anatomic sites of the tooth roots and underlying bone. A plan for the dental work is then generated based on the segmented anatomic sites, whereby the plan avoids periodontal defects based on the knowledge of the anatomic sites of the roots and underlying cortical bones in the dental model.