Scandinavian approach versus RPI system
My answer: The attached design comparison demonstrates the engineering advantage of the Scandinavian approach when using a dental bar with metal backings in free end saddle protheses (Kennedy Classification I and II) compared to the RPI . The fulcrum of rotation (shown in red) onto the free end saddle for the Scandinavian design system is on the distal of the lower right premolar compared to the mesial of lower right premolar in the RPI system – which theoretically places more force on the distal abutment (premolar). However, the interdental contacts (shown in blue) of the dental bar resists rotation around the fulcrum limiting sinking of the saddle onto the supporting tissues (link at the end of this). This resistance to rotation has practical benefits in terms of comfort during chewing and occluding. This resistance to rotation can be demonstrated when pressing firmly downwards towards the saddle with a finger. There will be no sinking of the free end saddle because the multiple areas of contact from the dental bar on the natural teeth resist this. In my experience of using the Scandinavian approach I have not recorded any losses of the distal abutment support tooth. Another advantage of the Scandinavian design system is that should one of the anterior teeth require extraction an additional prosthetic tooth can be added to the dental bar via welding a metal tag and attaching a tooth as per attached photo.https://www.facebook.com/finlaysuttonremovableprosthodontist/videos/486849342184423/
Please join me for my next webinar 3 tomorrow on Fantastic Complete Dentures Webinar 3 of 5: Finlay’s fantastic complete dentures. The 7 secrets to great function and aesthetics Please click on the date links to go to zoom booking.
Tuesday 21st April 13.00 (GMT+1hour) British Summer Timehttps://us02web.zoom.us/…/u5Mrcu6uqDItpxc1gw3obeHu-SywaZLLqg
Tuesday 21st April 20.00 (GMT+1hour) British Summer Timehttps://us02web.zoom.us/…/uJIlc-qupz8sR2eLfueA_PctYFnM3go1Cg
Webinar 4 of 5: Finlay’s - How to give our patients superb immediate dentures. Please click on the date links to go to zoom booking.
Tuesday 28th April (GMT+1hour) 13.00 British Summer Timehttps://us02web.zoom.us/…/tZItd-6hqTMoyF49nDGRsjCyOhP_JQg2PQ
Tuesday 28th April (GMT+1hour) 20.00 British Summer Timehttps://us02web.zoom.us/…/vp0kcOCuqj0r2H_-0lRoo3oAVndTxoMRGw
Webinar 5 of 5: Finlay’s - Implant supported overdentures – protocols to ensure success Please click on the date links to go to zoom booking.
Tuesday 5th May 13.00 (GMT+1hour) British Summer Timehttps://us02web.zoom.us/…/vpIocOqoqzMiPvdZIgfBV6o-AAIUznalug
Tuesday 5th May 20.00 (GMT+1hour) British Summer Timehttps://us02web.zoom.us/…/vJQtdeytpz4uyA5LbwT0Z-H5f7nPb1Go4Q