The pull-out retention strength of different cements used in implant-supported fixed restorations

Aims: This study aims to compare the pull-out retention strengths of various luting cements used in implant-supported fixed prostheses.Methods: A total of 50 newly fabricated cobalt-chromium (CoCr) crowns and 50 standard abutments were used in the study. The specimens were divided into five groups based on the cement type, with ten unique specimens per group (n=10, N=50). Standard abutments with 2 mm gingival height (Nucleoss, Şanlılar Ltd. Şti. İzmir, Turkiye) and analogs with 3.8 mm diameter and 12 mm height were torqued to 30 N. Screw access holes were sealed using Teflon and light-cured composite (G-Aenial Achord, GC, Tokyo, Japan). Analogs were embedded in auto-polymerizing acrylic (Integra; BG Dental, Mersin, Turkiye). Abutments were scanned (Medit T510, Medit Corp., Seoul, South Korea), and CoCr crowns fitting to the abutments, with rings on the occlusal surface for pull-out tests and a 50 µm cement space, were designed using CAD software (Exocad GmbH). Crowns were fabricated additively via laser melting (Mysint 100 Dual Laser, Sisma S.p.A., Piovene Rocchette, Italy). Five different types of cements were used for cementation: zinc polycarboxylate (Adhesor Carbofine, PENTRON SpofaDental a.s., Jičín, Czech Republic), glass ionomer (Kavitan CEM, PENTRON SpofaDental a.s., Jičín, Czech Republic), zinc phosphate (Adhesor, PENTRON SpofaDental a.s., Jičín, Czech Republic), self-adhesive resin (G-CEM ONE, GC Corporation, Tokyo, Japan), and resin-reinforced glass ionomer (Meron Plus QM, VOCO GmbH, Cuxhaven, Germany). Specimens were stored in water at 37°C for 24 hours. Pull-out tests were conducted using a universal testing machine (SHIMADZU AGS-X, Shimadzu Corp., Kyoto, Japan). Data analysis was conducted using one-way ANOVA followed by Tukey's HSD post hoc test (SPSS).Results: Self-adhesive resin cement exhibited significantly higher pull-out retention strength than all other groups (p0.001).Conclusion: Self-adhesive resin cement demonstrated superior pull-out retention strength, suggesting a higher retentive potential compared to the other cements tested under these specific experimental conditions.