CAD0111

Fig. 1_The panorama image shows the situation prior to insertion of the XiVE S implants. Fig. 2_Two weeks after being uncovered, an open pick-up impression is made at implant level with an individual tray. Fig. 3_In order to check the accuracy of transfer, a bar made from autopolymerisate is manufactured on a screwed-in Friadent MP abutment and split into segments. Fig. 4_The individual tray for the pick-up impression with fixed pick-up screws. 24 I I industry report _ CAD/CAM bar restoration _Conventional or CAD/CAM? Today, dental technicians and implantologists ponder this ques- tion more frequently than ever. More and more often, they tend towards CAD/CAM. Owing to their tension-free fit, CAD/CAM-fabricated solutions are particularly well suited for the restoration of larger jaw sections. Deciding in favour of or against a CAD/CAMrestorationshouldthusalwaysbeateam decision. With his expertise and training, the dental technician is able to contribute considerably to an aesthetic and technically perfect result. To ensure successful prosthetic restorations, all the steps of a procedure—from planning through impressiontoinsertion—needtobeperformedwith utmost care. This is equally true for both conven- tionally cast work and CAD/CAM-fabricated struc- tures. With both methods, only a precise transfer of the oral situation to the model guarantees success. Precision is vital for both methods, particularly whenrestoringlargerjawsections.Outstandingre- sults can also be obtained with conventional cast- ing technology if the work is done accurately and withsufficientexperience.However,theriskofanill fit is substantially higher compared with modern CAD/CAMprocedures.Furthermore,wide-spanning and solid frameworks in particular enable cavities to arise and the framework to warp. Also, (partial) overheating of the melt, another potential quality flaw, is often observed with large volumes. These problems do not occur with CAD/CAM technology. _Therapy decision Our patient wished to regain a firm bite and unimpaired speech. She had already been wearing mucosa-supportedcompletedenturesfor20years, but was comfortable only with the maxillary den- ture. The grip of the mandibular prosthesis was inadequate owing to the resorbed alveolar ridge (Fig. 1) and obstructed eating and speaking. There were no general medical findings ruling out an im- plantation.Afterdetailedconsultation,weoptedfor a bar denture on four implants placed inter-foram- inally in the mandible. A fixed restoration was not possible owing to cost considerations. A prosthesis CAD/CAM 1_2011 Fig. 1 Fig. 2 Fig. 3 Fig. 4 For a perfect fit—CAD/CAM bar restoration on XiVE implants Authors_ Björn Roland & Dr Peter Gehrke, Germany