Is There a Correlation Between Tensile Strength and Retrievability of Cemented Implant-Retained Crowns Using Artificial Aging?

Purpose: The main goal of this in-vitro study was to evaluate whether tensile strength and retrievability of cemented implant-retained crowns correlate when using artificial aging. Materials and Methods: A total of 128 crowns were fabricated from a cobalt-chromium alloy for 128 tapered titanium abutments (6 degrees taper, 4.3 mm diameter, 4 mm length, Camlog). The crowns were cemented with glass-ionomer (Ketac Cem, 3M) or resin cements (Multilink Implant, Telio CS Cem [Ivoclar Vivadent], Retrieve [Parkell]). Multilink Implant was used without priming. The experimental groups were subjected to either 37,500 thermal cycles between 5°C and 55°C, 1,200,000 chewing cycles, or a combination of both. Control groups were stored for 10 days in deionized water. The crowns were removed with a universal testing machine or a clinically used removal device (Coronaflex, KaVo). Data were statistically analyzed using nonparametrical tests. Results: Retention values were recorded between 31 N and 362 N. Telio CS Cem showed the lowest retention values, followed by Retrieve, Ketac Cem, and Multilink Implant (P ≤ .0001). The number of removal attempts with the Coronaflex were not significantly different between the cements (P > .05). Thermal cycling and chewing simulation significantly influenced the retrieval of Retrieve Telio CS Cem, and Ketac Cem specimens (P ≤ .05). Only for Multilink Implant and Telio CS Cem correlations between removal with the universal testing machine and the Coronaflex could be revealed (P ≤ .0001). Conclusions: Ketac Cem and Multilink Implant (without silane) can be used for a semipermanent cementation. Retrieve and Telio CS Cem are recommendable for a temporary cementation.