When planning for guided surgery in edentulous patients, it is important to have the final vertical dimension and tooth position determined. Ideally, a denture duplicate should be used with proper radiographic markers.
The traditional way was to embed radio-opaque material in the denture dupe, CT scan the patient with the denture dupes, and then CT scan the denture dupes themselves. Alternatively, you can scan the denture duplicates with a digital impression system. Here we used flowable composite and spread them through the wax set up and take a 3D X-ray of the patient. We then use those landmarks to merge the data sets between the digitize denture and the markers on the CT Scan
Once the dentures are digitized and merged with the CT data, the cases is analyzed to make sure there are no gaps in between the intaglio of the denture and the soft tissue of the palate and the lower / mandibular ridge
An important concept to keep in mind for these edentulous cases is that you actually need 2 models for each arch. One model is used for tooth positioning and implant design, and the other model is used for stent design. Essentially, you design the stent on the ridge, not the denture dupe