RETENTIVE STRENGTH OF CEMENTRETAINED IMPLANT-SUPPORTED FIXED DENTAL PROSTHESES ACCORDING TO DIFFERENT CEMENT TYPES AND CEMENTATION PROTOCOLS: AN IN VITRO STUDY.

Purpose: To develop the most compatible cementation protocol for ensuring minimal residual cement and optimal retention of cement-retained implant-supported fixed dental prostheses.

Materials and methods: A total of 30 custom implant abutments and zirconia crowns with bilateral wings were prepared. Three cement types were used for cementation: noneugenol resin cement (Premier Implant Cement; Group IC), dual-polymerizing self-adhesive resin cement (SmartCem2; Group SC), and zinc oxide eugenol cement (Temp-Bond; Group TB; n = 30 per group). Three cementation methods were applied for each cement type, and the samples were divided into subgroups: (1) cement was injected using a graduated syringe (ICN, SC-N, and TB-N); (2) a cementa/on jig made with a silicone impression material and temporary resin material was used (IC-CJ, SC-CJ, and TB-CJ); (3) 3D-printed abutments were used as replicas for cementation (IC-3DP, SC-3DP, and TB-3DP). The amount of cement injected, surface area of the residual cement, and retentive strength were measured. Kruskal- Wallis and post-hoc Mann-Whitney tests were used for statistical analyses.

Results: Excess cement was not observed when cementa/on jig or 3D-printed replicas were used. For IC and SC subgroups, non-use of these auxiliary tools resulted in significantly higher amounts of injected cement. The retentive strength differed significantly among the IC subgroups but not among the SC subgroups. The retentive strength of subgroups TB-N and TB-CJ was significantly higher than that of subgroup TB-3DP.

Conclusions: To prolong the main purpose of each cement type, a cementation jig or 3D-printed replica is highly recommended regardless of the cement type.