Interface between MTA and dental bonding agents: Scanning electron microscope evaluation

Aims and Objectives: Nowadays, the material that offers the best sealing characteristic in the field of endodontic treatment is the mineral trioxide aggregate (MTA), nevertheless, this material necessities an adhesive bonding agent to perfectly join to the dental surface. The aim of this study was to analyze using a scanning electron microscope (SEM) the possible microgap between the adhesive, MTA, and the dental surface. Material and Methods: Fourteen extracted molars were divided into two groups - group A was prepared with MTA-component adhesive and group B was prepared with MTA and composite dual etching. The observations were carried out with a SEM Phenom G2 Pro mode S.E.I. JMP® software was used for statistical analysis, and a t-test was used for evaluating the difference between the two groups. Results: The gap of the areas at higher magnification (1000×) with a size greater than 5 microns in width and 20 microns in length were considered significant, and only group A recorded significant data. Conclusions: The SEM analysis performed in the group A with interposition of adhesive and flow between the dental pulp chamber and MTA demonstrates the presence of a marginal gap of considerable amplitude in the all of the samples investigated.