Zirconia ceramic inlay-retained fixed dental prostheses - first clinical results with a new design

ObjectivesThe purpose of this prospective study was to evaluate the clinical outcome of inlay-retained fixed dental prostheses (IRFDPs) with a new design made from a zirconia ceramic.MethodsTwenty-three 3-unit IRFDPs were placed in 23 patients, restoring five second premolars and 18 first molars. Preparations were performed in accordance with general principles for ceramic inlay restorations and modified with a retainer-wing bevel preparation in the enamel at the buccal and oral sides. The frameworks were scanned and milled out of zirconia ceramic, using the InLab CAD/CAM-system and the pontics were veneered with feldspathic ceramic. All IRFDPs were luted adhesively with composite resin. Clinical follow-up examinations were performed annually. Statistical analysis was performed using descriptive statistics and Kaplan-Meier survival analysis.ResultsAll patients with their 23 IRFDPs could be examined clinically after a mean observation time of 20 months. None of the IRFDPs failed. Two ceramic veneers fractured, both of them needed repair. One restoration debonded, but was recemented immediately. However, these technical complications did not affect the clinical function of the IRFDPs involved.ConclusionsThe clinical outcome of zirconia ceramic IRFDPs with the modified design seems promising.