RESUMO
The success of endodontic surgery has been shown to depend partly on the apical seal. Grey mineral trioxide aggregate [GMTA] produces hydroxyapatite twice as often as white mineral trioxide aggregate [WMTA] when suspended in a phosphate buffered saline [PBS] solution. The aim of this in vitro study was to compare the microleakage phenomenon of gray and white mineral trioxide aggregates as root-end filling materials after immersion in synthetic tissue fluid [STF]. 55 single-rooted extracted maxillary anterior human teeth were divided into two experimental groups of 20 teeth each, plus 3 groups of 5 teeth each as two negative and one positive control groups. The root canals were cleaned, shaped, and laterally compacted with gutta-percha. The root ends were resected and 3 mm deep cavities were prepared. The root-end preparations were filled with GMTA or WMTA in the experimental groups. Leakage was determined using a dye penetration method. Data were analysed using analysis of variance [ANOVA] at the 0.05 level of significance. Results: The mean dye leakage was 0.40 +/- 0.1 mm for GMTA and 0.50 +/- 0.1 mm for WMTA groups, respectively. There was no significant difference between the two experimental groups [P = 0.14]. Despite the different properties and behaviours of GMTA and WMTA in STF, there were no significant differences in microleakage when using GMTA or WMTA