• Chalita Tanasamanchoke
• Chairat Wiwatwarrapan B.Sc, M.S

Objective The interface between denture base and hard reline resin can be improved with chemical
surface treatment, methyl formate-methyl acetate (MF-MA) solution, by dissolving the relined
surface.This study evaluated the effect of various MF-MA wetting times on the tensile bond strength
between a non-methyl methacrylate (MMA) based reline material and denture base.

Materials and Methods One hundred plates of heat-cured denture base resin (Meliodent^®) were
prepared according to ISO 10139-2 and randomly divided into five groups: control and four experimental
groups treated with CU Acrylic Bond, MF-MA at a ratio of 25:75 by volume, for 15, 30, 60,
and 180 s, respectively. The groups were applied with a non MMA-based hard reline material (Kooliner^®)
between two plates of denture base resin. The tensile bond strength tests were performed using a
universal testing machine. Denture base specimens were analyzed by scanning electron microscopy
(SEM) to determine the surface morphology. The data were analyzed using one-way ANOVA and
post hoc Tukeyûs analysis at p<0.05.

Results The tensile bond strength of the experimental groups were significantly higher than that of
the control group (p<0.05). There were no significant differences between the experimental groups
(p>0.05). The SEM images of the denture base groups indicated that the denture base specimens
treated with MF-MA demonstrated a porous appearance compared to the control group.

Conclusion Surface treatment with MF-MA increased the bond strength between denture base resin
and hard reline material. However, the length of time of treatment had no effect on bond strength.

(CU Dent J. 2015;38(Suppl):75-72)