Methods: Twenty four noncarious superior third molars.The root apex was sealed with amalgam and acrylic resin (Duralay). Cavities of 2,5mm (mesio-distal), 2,0mm (oclusal-gengival) and 2mm of depth were made in the teeth buccal surface. These cavities were conditioned with phosphoric acid 37% for 15 seconds, then were rinsed with water for 10 seconds and were dried with absorbent paper. Adhesive system Scotchbond Multipurpose Plus (3M) was applied to cavities, which were dried for 3s and then cured for 20s. The twenty four cavities were filled once with Charisma (Kulzer) composite, color A 3.5, and were divided in four groups: Group 1 = cured with halogen light KM 200R for 40 seconds, as a control group; Group 2 = cured with LED’s Ultrablue III (DMC) for 40 seconds; Group 3 = cured with Ultraled (Dabi Atlante) for 40 seconds; Group 4 = cured with LED’s Ultrablue II (DMC) for 40 seconds. All the groups were thermo cycled 1.000 times at 5°C and 55°C, and then were included in fuchsine basic solution for 12 hours. After this, teeth were cut at the middle of the restorations, parallel to teeth vertical axis. In order to determine micro leakage levels, each part was observed and analyzed in a stereoscopic Zeiss microscope (100X).
Results: Mann-Whitney and Kruskal-Wallis statistical tests were used in order to analyze microleakage levels. The first one showed a non parametric distribution, and the second one had two degrees of freedom for the four groups. There was no great difference between the four groups evaluated.
Conclusion: For enamel microleakage, there is no difference between any of the curing devices used in this study.