Water-induced Effects on the Hardness and Modulus of Contemporary Sealants Derived from Instrumented Indentation Testing (IIT).

AIM

To compare the mechanical properties of four different types of contemporary fissure sealants before and after water storage employing a modern instrumented indentation testing (IIT) method.

MATERIALS AND METHODS

Four different types of materials used in everyday practice were deliberately selected. Fissurit (FIS) is a highly filled resin, Embrace (EMB) is a bisphenol A (BPA)-free unfilled resin, Helioseal (HEL) is an unfilled resin, and Riva Protect (RIV) is a glass-ionomer material. Six cylindrical specimens from each material were prepared (: 3 mm, : 15 mm), and Martens hardness (HM), elastic modulus (), elastic index (), and Vickers hardness (HV) were determined employing an IIT machine according to International Organization for Standardization (ISO) 14577:2015. Then, the samples were stored in water at 37°C for 48 hours and measured again at the same surface. The mechanical properties tested (HM, , , and HV) were statistically analyzed by two-way repeated measurements analysis of variance (ANOVA) employing materials and conditions as discriminating variables. Statistically significant differences were identified by Tukey's post hoc multiple comparison test. In all cases, a 95% level of significance was set ( = 0.05).

RESULTS

Statistically significant differences in selected mechanical properties were allocated among materials tested. The artificial aging had a detrimental effect on HM, , and HV apart from for FIS, EMB, and HEL. In contrast, no significant differences were identified for RIV before and after water storage for all aforementioned properties apart from .

CONCLUSION

Significant differences were identified in mechanical properties among materials tested and thus differences in their clinical behavior are anticipated.

CLINICAL SIGNIFICANCE

This study contributes to the understanding of the mechanical properties of different dental sealants with respect to water contact, which may influence the choice by the therapist.