Evaluation of HEMA released from four different adhesive systems by HPLC

Purpose: This study evaluated the elution of 2-hydroxyethyl methacrylate (HEMA) from 4 different adhesives, using highperformance liquid chromatography (HPLC). Materials and methods: The adhesives were applied on a bovine dentin surface and polymerized using an LED curing unit (n=5). After polymerization, specimens were stored in 75% ethanol solution (6 mL). Residual HEMA that was eluted from adhesives (after 10 minutes, 1 hour, 24 hours, 7 days and 30 days) was analyzed using HPLC. Statistical analyses were performed using 1-way ANOVA, Tukey HSD test and paired 2-sample t-test. Results: There were statistically significant differences among adhesive systems for the cumulative released HEMA and among the time periods (p<0.05). Clearfil SE Bond showed the highest amount of HEMA released, while Easy Bond showed the lowest. Among the time periods, the highest eluted HEMA value was detected in 10 minutes for all adhesives, and elution continued for up to 30 days. Conclusions: The HEMA eluted from adhesives was in different amounts, and the elution continued for a long time. The amount of eluted HEMA from adhesives used in this study was not viewed as critical for toxic reactions in biological tissues.