Method:
The root canals of single-rooted extracted human teeth were prepared by using Protaper Universal rotary files and divided into 3 experimental groups (n =14/group) with respect to the filling technique tested: Group 1, GuttaCore and TopSeal sealer; Group 2, Thermafil and TopSeal sealer; Group 3, System B and TopSeal sealer and into 2 control groups: Group 4, Positive control; Group 5, negative control.
The microleakage of specimens was measured using a nuclear medicine method after 1 week of obturation.
Two coats of nail polish were applied to the external surface of each root except for the 1 mm apical root end, unlike the negative control group, where the root ends were also sealed with nail polish. On the 7th day the apices of the teeth were submersed in a solution of 99mTc-Pertechnetate for 3 hours. The radioactivity was counted using a gamma counter and a gamma camera.
Data were analyzed statistically with R software package (α= 0.05).
Result: The results revealed statistically significant differences between the 2 control groups and the 3 experimental groups with respect to the microleakage (Mann-Whitney test). Within the experimental groups no statistically significant differences were found (Kruskal-Wallis test) between the groups (p= 0.2541).
Conclusion:
The apical sealing efficiency of obturation techniques after 1 week, obtained with nuclear medicine testing in vitro, was similar.
Results show the good sealing ability of both techniques making them appropriate to use in daily endodontic obturations.