Summary: The target of the thestudy was to compare the reliability of adhesive systems of Vth. and VIth generation by thermocycling according to method ISO/TS 11405:2003 (E). For comparison there were chosen two representatives from each group - from the Vth generation materials Single Bond Adper and Prime&Bond NT and from the VIth generation materials Prompt-L Pop Adper and Xeno III. The materials of the Vth generation were combined with advised etching gels and by all adhesives the directions for use were strictly followed. Adhesive systems were combined with materiál Spectrum TPH. Each adhesive systém was tested on 10 samples of intact third molars. The results showed extensive variability among reliability single adhesives without dependence to generations, that means self-etch or conventional total-etch. While measuring microleakage according to ISO/TS 11405:2003 (E) was the most reliable Prime&Bond NT, with score 12, than Xeno III with score 26. Between reliability of Single Bond Adper (score 37) and Prompt L-Pop Adper (score 38) there was no significant difference. The results demonstrated no significant difference between single generations of adhesive systems and proved that the quality of each product is the most important, whether it belongs to self-etch or conventional total-etch generations.

        Key words: adhesive systems - thermocycling