This study investigated the effect of methyl formate-methyl acetate (MF-MA) wetting times on the tensile bond
strength (TBS) between 3 non-MMA based reline materials and denture base material. Four hundred heat-cured
denture base resin (Meliodent®) were prepared and randomly divided into 3 groups according to hard reline resins
(Kooliner®, Tokuyama® Rebase II and Ufi Gel Hard®). Each group of reline material consisted of 6 or 7 subgroups
(n=10), based on their surface treatment; control, adhesive, MF-MA 15, 30, 60, 180 s and MMA 180 s. The TBS test
was performed using a Universal testing machine. Data were analyzed using one-way ANOVA and post hoc Tukey’s
analysis at p<0.05. The means TBS of the treated groups were significantly higher compared with those of the
control group (p<0.05). In the Kooliner® groups, there were no significant differences in TBS between the MF-MA
and the MMA treatment groups (p>0.05). In the Tokuyama® Rebase II groups, application of MF-MA solutions for
180 s produced the highest TBS compared with the other groups (p<0.05). In the Ufi Gel Hard®, the groups of MF-MA
180 s and MMA 180 s groups demonstrated significantly higher TBS compared with the other groups (p<0.05). Surface
treatment with MF-MA solutions significantly increases the TBS between denture base resin and non-MMA hard
reline resins. This study suggests that an MF-MA wetting time of 15 s for Kooliner® and 180 s for Tokuyama® Rebase
II and Ufi Gel Hard® is adequate for creating a strong bond.