The Influence of Amine Contents in Experimental Acrylic Resin on The Flexural Strength and Cell Cytotoxicity

Abstract

Background/Objectives: The purpose of this study was to evaluate the influence of benzoyl peroxide(BPO) and amine ratio on the flexural strength and cell cytotoxicity of acrylic resin.

Methods/Statistical analysis: To prepare the specimens, six experimental acrylic resin groups were prepared depending on BPO:amine ratio followed by 1:0.25, 1:0.5, 1:0.75, 1:1, 1:1.25, 1:1.5 mol%. To measure mechanical properties, three point bending test was carried out according to ISO 4049 specification. The cytotoxicity test was carried out according to ISO 10993-5 specification. The residual monomers of fully polymerized resin materials were identified using gas chromatography/mass spectrometry. All data were statistically analyzed by a one-way ANOVA.

Findings: Groups with A0.25 and A0.5 showed significantly lower level of flexural strength that other experimental and control groups (p < 0.05). Flexural strengths were increased according to the increasing proportions of amine. Groups with A0.75, A1, A1.25 and A1.5 had no statistically significant difference compared to control group (p > 0.05). Flexural strengths were increased as the proportion of amine was increased. The cytotoxicity of each group exhibited increasing cell viability as more amine was added (Figure 2). Groups with A0.25, A0.5, and A0.75 had a significantly higher cytotoxicity than other experimental and control groups (p < 0.05).  Groups with A1, A1.25 and A1.5 had no statistically significant difference compared to control group (p > 0.05). The cytotoxicity of each group exhibited increasing cell viability as more amine was added. The residual monomer tended to decrease as the proportion of amine increased. It was considered that the amount of BPO:amine ration should be carefully adjusted in order to minimize the harmful effect of residual monomer.

Improvements/Applications: Based on these results, the distribution of amine content in the liquid should be uniform when used in clinical practice as the amine content affects the properties of acrylic resin.