Introduction: Thin, non-retentive, monolithic restorations fabricated from novel translucent zirconia ceramics are widely used in contemporary dentistry. Because of zirconia's chemical inertness, debonding such restorations remains the main clinical complication. Airborne- particle abrasion (APA) is a currently clinically accepted zirconia pretreatment method. However, APA can lead to zirconia strength degradation and premature failures, therefore, non-invasive pretreatment with a nanostructured alumina coating (NAC) has recently been proposed. NAC is an additive pretreatment method and does not impair the mechanical nor optical properties of zirconia. Limited evidence on the bonding performance of novel translucent zirconia exists. Purpose: Therefore, the present study aimed to in vitro evaluate the shear-bond strength (SBS) of translucent zirconia, materials containing 3, 4, or 5 mol.% of yttria modified with NAC and compare it SBS to airborne-particle abraded (APA) zirconia surfaces.
Methodes: Scanning electron microscopy was performed to qualitatively evaluate the resin- zirconia bond. Results: NAC provided higher resin-zirconia SBS compared to APA, while SEM analysis has shown a predominant cohesive failure in all NAC groups, where the NAC stayed firmly attached to the zirconia surface. Discussion and conclusion: NAC does not impair the mechanical or optical properties of translucent zirconia materials and should be regarded as a zirconia pretreatment alternative to APA. In the second part of the diploma work, a translation of NAC from the laboratory to clinical application was done. A 17-year- old patient was rehabilitated with a resin-bonded fixed dental prosthesis. The retainer wing of the RBFDP was coated with NAC to achieve optimal bonding and to avoid damaging the novel translucent zirconia ceramic.
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