• Maytinee Vivathanasittiphong D.D.S.
• Napapa Aimjirakul D.D.S., Ph.D.
• Teerachai Limlawan D.D.S., M.S.

Objectives: Compare the push-out bond strength of a dual-cured core build-up resin composite and
dual-cured resin cement using total-etch adhesive for bonding fiber post to root canal dentin.

Materials and Methods: Sixty extracted single-rooted human premolars were sectioned transversely
in mesiodistal direction 2 mm coronal to cementoenamel junction, standard endodontically treated, post
space prepared and randomly divided into two groups (n=30). Group 1 fiber posts were luted with a
total-etch resin cement (Variolink^® II) and group 2 were luted with a composite resin core build-up
material (Luxacore^® Z-Dual) using total-etch adhesive system. All roots were cut transversely into
3 sections (coronal (L1), middle (L3) and apical (L5)) with 1 mm thicknessin each section.
The push-out test was performed at a speed of 0.5 mm/min. Failure modes were evaluated using a
scanning electron microscope (65x). The data were analyzed using ANOVA and post hoc Tukeyûs
test (p < 0.05).

Results: In 3 root canal regions, the mean push-out bond strength of Luxacore^® Z-Dual showed
significantly higher bond strength than Variolink^® II (p < 0.05). Means push out bond strength of both
Luxacore^® Z-Dual and Variolink® II at cervical region were higher than those of middle and apical
regions (p < 0.05). The analysis of failure modes revealed that most of the failures were adhesive
failure.

Conclusion: Regional push-out bond strength of Luxacore^® Z-Dual resulted in significantly higher
bond strength than Variolink^®II and this method could be considered as an alternative technique to
luted fiber post within root canal.

(CU Dent J. 2015;38:111-000)