Comparison of the compressive and diametral tensile strengths of currently used luting agents – an in-vitro study

This in-vitro study evaluated the Compressive and Diametral tensile strengths of currently used luting agents, compared and analyzed the strength properties of various brands of luting agents and recommended the most effective luting agent based upon the observations of the study.

The mechanical properties namely compressive strength and diametral tensile strength of four routinely used luting agents namely Zinc Phosphate, Zinc Polycarboxylate, Glass Ionomer and Resin Modified Glass Ionomer cement were evaluated. To accomplish the study, cylindrical samples measuring 5 mm in diameter 7.5 mm in height were made, stored in distilled water at room temperature for 24 hours and then subjected to load tests with the help of a Hounsfield tensometer.

Resin modified Glass Ionomer cements had the highest compressive strength followed by Zinc Phosphate, while Glass ionomer cement and Zinc Polycarboxylate had the least. Resin Modified Glass Ionomer cement was again found to have the highest Diametral tensile strength followed by Glass ionomer cement, while Zinc Polycarboxylate and Zinc Phosphate had the least.

Statistical analysis showed highly significant results for all the cement groups. Resin modified Glass Ionomer cement being the most superior in comparison to the other three groups.