Please activate JavaScript!
Please install Adobe Flash Player, click here for download
ePaper created 2016-01-07, 12:59:38 | version 1.38.0
I case report _CAD/CAM is playing an increasing role in the productionofimplant-retainedprostheses.Thesedig- ital technologies constitute a major advancement in termsoffitaccuracyofthesuperstructure.1, 2 Rehabil- itating a fully edentulous upper jaw with an implant- retained overdenture may require delicate treatment becauseofthebiomechanicalandanatomicalconsid- erations associated with severe bone resorption. This article describes the contribution of these new digital technologies to the construction of milled bars for rehabilitation in such cases. _Case presentation A 75-year-old non-smoking female patient, whose rheumatoid polyarthritis has been treated with methotrexate for seven years, presented. This patienthasbeenfullyedentulousintheupperjawfor 30 years. She wore a removable partial denture in the lower jaw and a removable complete denture in the upper jaw. Stability of the latter was very precarious owingtoseverecrestalboneresorption.Thepatient’s motivations were mostly function orientated; she was eager to regain chewing comfort. There are centrifugal forces in the lower and cen- tripetal forces in the upper jaw, and bone resorption reduces the volume of the latter, causing an offset between the upper and lower jaws. This offset, which was to be compensated for by the overdenture, must be taken into account at implant placement. Pre-implantationsurgery DentaScan (GE Healthcare) allows the evaluation, asacomplementtotheinitialpanoramicradiograph, of the residual bone volume available for implant- retained rehabilitation. In the present case, this ex- aminationconfirmedthattheupperjawwasatrophic (Figs.1&2).Therefore,bonereconstructionwasnec- essarypriortoimplanttreatment.Abilateralsinuslift with lateral access was performed. The space under CAD/CAM custom-milled titanium bar for rehabilitation of an atrophic upper jaw Author_ Dr Richard Marcelat, France 26 I implants4_2015 Figs. 1 & 2_Scans showing severe bone resorption and atrophy of the upper jaw. Fig. 1 Fig. 2 Fig. 3a