Adhesive Failure of Lava Ultimate and Lithium Disilicate Crowns Bonded to Zirconia Abutments: A Prospective Within-Patient Comparison

Purpose: To demonstrate the influence of restorative material on the success of clinical bonding to zirconia. Materials and Methods: A total of 50 participants with a single implant received screw-retained restorations; ie, Lava Ultimate (LU) crowns extraorally bonded to zirconia abutments. After 1 year, lithium disilicate (LDS) was used as an alternative restorative material. These restorations were also followed for 1 year. Results: Forty LU restorations (80%) debonded within 1 year of clinical service, whereas no bonding failures occurred with LDS restorations. Conclusion: The choice of restorative material for single crowns luted to zirconia implant abutments strongly influences the incidence of bonding failures.