Abstract
OBJECTIVE: The study focused on drawing a comparative evaluation amongst four commercially available implant luting cements used to retain implant-supported zirconia restorations fabricated using a Computer-Aided Design-Computer-Aided Manufacturing (CAD-CAM) system. MATERIALS AND METHODS: A heat-activated polymethyl methacrylate (PMMA) model was fabricated to mount four implant abutment-analogue complexes. These complexes were scanned using a digital laboratory scanner to mill 60 zirconia copings using CAD-CAM software. The copings were divided into four groups depending on the type of implant luting cement used (n = 15). The zirconia copings were then cemented over titanium abutments and a tensile load at a crosshead speed of 1 mm/min was applied to the samples to perform a pull-out test using Universal Testing Machine. Thereafter, the load required to de-cement each coping was obtained, thus the retention for each coping was measured. STATISTICAL ANALYSIS: One-way analysis of variance (ANOVA) was advocated to statistically analyse the results and the post hoc Bonferroni test was used for multiple comparison using Statistical Package for the Social Sciences (SPSS) software. RESULTS: Multilink implant showed highest tensile strength (2.24 ± 1.01 kgf/mm(2)) being statistically significantly different from the other three cements (p < 0.001). This was followed by TgImplaCem (0.82 ± 0.32 kgf/mm(2)) and Temp-Bond NE (0.71 ± 0.13 kgf/mm(2)). The lowest tensile strength was exhibited by ImplaLute (0.31 ± 0.10 kgf/mm(2)). Intergroup comparison between TgImplaCem, Temp-Bond NE, and ImplaLute cements did not show statistically significant difference in tensile strength values (p < 0.001). CONCLUSION: It was concluded that both non-eugenol zinc oxide provisional luting cement (TgImplaCem) and dual-curing resin-based implant cement (Temp-Bond NE) can be advocated to cement implant-supported prostheses since they both permit adequate retention with ease of retrievability.