Influência do tratamento com MTA na resistência de união de pino de fibra

Abstract

The literature indicates that there is a good interaction between biomaterials such as tooth, Mineral Trioxide Aggregate - MTA, resin cement and fiberglass posts, however, the question about the resistance and type of union as well as the type of failure between MTA and resin cements remains. Due to the risk of root perforations, an existent alternative is the restoration with MTA, which must integrate with the post / cement system. The aim of this study was to evaluate the influence of root perforation restored with MTA on the bond strength of fiberglass posts luted with a self-etch resin cement. Twenty inferior bovine teeth were selected and had their crowns removed, remaining 16mm of radicular remnant followed by endodontic root treatment; Division of the specimens into two groups, being: group I - without perforation, group II - perforation of 1mm restored with MTA in the apical, middle and cervical thirds. Soon after, the preparation and the luting of the posts was performed; The specimens were kept in a dye solution (2% methylene blue) for 1 day in a conservatory. After that, section of the roots was performed in order to obtain the specimens; Test of resistance to shear "push-out" was executed and finally the microscopy aiming to quantify infiltration. Statistical analysis was performed by ANOVA test (p <0.05), the results were not statistically significant. The resistance means (kgf) of group I-68.58 (cervical), 66.94 (middle) 54.56 (apical), and group II- 74,26; 66.67 and 69.59 respectively. The percolation data indicates good sealing in the passage of humidity, showing good interaction between the biomaterials in cases of perforations.