One-Piece Monolithic Zirconia Single Tooth Implant-Supported Restorations in the Posterior Region: A 1-Year Prospective Case Series Study

OBJECTIVE: To assess the clinical, radiographic and patient-reported outcome measures, and the success of screw-retained one-piece monolithic zirconia implant-supported restorations in the posterior region during a 1-year follow-up.

METHODS: In a prospective case series, 50 single molar sites in the posterior region of 41 patients with a minimum age of 18 years and sufficient bone volume for placing an implant (≥ 8 mm) and space for an anatomical restoration were included. Following prosthetic-driven digital three-dimensional treatment planning, a tissue-level implant with an internal connection was inserted during a one-stage surgical procedure. Three months later, the implant was restored with a screw-retained one-piece monolithic zirconia restoration. Clinical, radiographic and patient-reported outcome measures, and restoration survival and success according to the modified USPHS criteria were assessed at baseline prior to and immediately after implant placement, and 1-month and 1-year after definitive restoration placement.

RESULTS: At the 1-year follow-up, 1 implant had been lost (implant survival rate 98%) hence, 49 restorations were evaluated. The restoration survival and success rates were 100% and 98%, respectively. Plaque, calculus, bleeding and suppuration on probing and peri-implant inflammation were absent in most cases. The mean (SD) marginal bone level change between implant placement and the 1-year follow-up was -0.14 mm (0.27) on the mesial and -0.25 mm (0.31) on the distal side. The mean (SD) patient satisfaction (0-10) was 9.2 (0.8) at the 1-year evaluation.

CONCLUSION: One-piece monolithic zirconia implant-supported restorations exhibited favourable outcomes over 1 year in situ.

TRIAL REGISTRATION: Registered in the National Trial Register (NL9059).