The investigation of the effects of novel composites applied with different layering techniques on microleakage

Objective: Microleakage is one of the major problems of restorative dentistry. The aim of this in vitro study was to evaluate the microleakage potential of novel composite materials applied with either incremental or bulk fill technique using dye penetration method. Method: Standard Black I cavities were prepared (3mm x 3mm x 4 mm) to 120 freshly extracted molar teeth. A nanohybrid (Filtek™ Z550), a bulk fill (X-tra fil) and a ceramic reinforced bulk fill composite (Admira Fusion X-tra) was tested. Bulk fill and incremental application techniques were used as restoration method. Specimens were randomly separated in 6 group (n=20) and after restorative procedures, samples were thermal cycled for 1000 cycles (5ºC-55ºC). Microleakage test was applied with using %1 methylene blue dye. Sections of the teeth were evaluated under stereo microscope in terms of dye penetration degree. Statistical analyses were conducted with Kruskal-Wallis and Mann-Whitney-U tests (p=0.05). Results: The relationship between composite resin groups and microleakage degrees were statistically significant (p<0.05). The higher microleakage scores were observed in X-tra fil bulk fill group followed by Filtek™ Z550 incremental group (p<0.05). Admira Fusion X-tra with incremental application technique showed least microleakage. With exception of Filtek™ Z550, a significant difference between two layering technique was observed in all composite (p<0.05). Conclusion: Admira Fusion X-tra exhibited the lowest microleakage degree when it was prepared with incremental application techniques.