Nulty-Waith CAD Implant Scan Ladder

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The Nulty-Waith CAD Implant Scan LadderDigital Intraoral Scanners (regardless of brand of scanner technology) have an inherent loss of accuracy when scanning large edentulous areas due to the method of capturing and stitching hundreds of small images based on surface morphology. In some cases where there are very flat or featureless areas this can affect cross arch accuracy and passivity in large restorations. Chris Waith came up with the idea to link scan bodies in some way. I suggested to make an extendable ladder connecting the scan bodies in a way that doesn't impact or impede the scan body features required for the CAD software recognition. (I've put the development pics here too to see ;-) ). I have designed this in Meshmixer and the download to this STL will be FREE for both Free and Premium International Digital Dental Academy members on the Resource page.You can print it on any 3D printer to aid your full arch scanning. The beauty of full arch implant scanning with this using DIOS scanners is you can scan, remove the aids, then "just" scan the scan bodies again in those sections to get a better image and the software automatically removes most of the bridge.I have then used CloudCompare to compare the reference STL to the scan with the bridge and without the bridge. The scan with the Nulty-Waith ladder is pretty much perfect (less bright green), the scan without the ladder has a deviation to the buccal and vertical as the scan has proceeded around the arch.As Phil Reddington has discussed on the DDA group previously, the accuracy of chair side digitally scanned full arch cases requires checks, sectioning and verification for full passivity unless pickups are done so anything to improve this will help, hence making this free to use.This is free to download and share but please credit the sourcewww.idda.org