The evaluation of interfaces between MTA and two types of GIC (conventional and resin modified) under an SEM: An in vitro study

CONTEXT: Mineral trioxide aggregate (MTA) is a biocompatible repair material that is often used along with glass ionomer cement (GIC) in many clinical situations. AIMS: In this study, the interface of GIC and MTA was examined, and the effect of time on this interface was tested. MATERIALS AND METHODS: Forty 9-mm hollow cylindrical glass molds were filled with MTA and then according to the group either conventional GIC or resin-modified GIC (RMGIC) is filled immediately or after 45 min. The specimens were then sectioned, carbon coated, and examined using a scanning electron microscope (SEM) and the elemental analysis was done. STATISTICAL ANALYSIS: Observational study, no statistical analysis done. RESULTS: The SEM showed that both the groups underwent adhesive separation and gap formation at the interface. The specimens in which GIC was condensed over freshly mixed MTA (group IIA and group IIB) also showed cohesive separation in MTA; however, it was more in the GIC condensed after 45 min over MTA groups (group IA and group IB). The results were better for conventional GIC than RMGIC. CONCLUSIONS: GIC can be applied over freshly mixed MTA with minimal effects on the MTA, but this effect decreases with time.