Clin Oral Implants Res. 2025 Apr 29. doi: 10.1111/clr.14443. Online ahead of print.
ABSTRACT
OBJECTIVES: This study compares the cumulative survival and technical complications of screw-retained implant-supported lithium disilicate crowns (SICs) on polyether ketone ketone (PEKK) base abutments and zirconia implants with those of titanium base abutments and titanium implants.
MATERIALS AND METHODS: Sixty participants were randomly and evenly assigned to receive zirconia or titanium implants. Survival and technical complications were assessed at 6 weeks after crown placement (baseline) up to 36 months. The cumulative survival of the SICs was analysed as a non-inferiority design, assuming that the difference between the titanium group and the zirconia group is not more than 10%. Technical complications were assessed based on modified USPHS criteria and Pink Aesthetic Score (PES).
RESULTS: In the zirconia group, three early implant failures occurred; all of them were successfully revised. After baseline, three implants in the zirconia group were lost due to insufficient osseointegration, and therefore the SICs have to be categorised as failures even though none of the SICs failed. The non-inferiority of the zirconia group could not be confirmed, as the cumulative survival was 10.7% lower compared to the titanium group (100%). The technical complication rate was low, with no statistically significant difference between the groups. The PESs improved significantly compared to baseline, with no significant difference between the groups at 12 months.
CONCLUSION: Hybrid abutment SICs with PEKK base abutments on two-piece zirconia implants could be an alternative to hybrid abutments SICs with titanium base on titanium implants. However, the lower osseointegration rate of the zirconia implants has to be considered.
TRIAL REGISTRATION: This study was registered in the German Clinical Trial Register (Deutsches Register Klinischer Studien) (number: DRKS00014866).
PMID:40297919 | DOI:10.1111/clr.14443
