Assessment of a novel antifungal ionic liquid-mediated silicone denture base soft liner

This in vitro study aimed to develop a novel choline-based ionic liquid-incorporated silicone denture base soft liners (SDBSLs) with improved antifungal potential and compliance in standard properties.

Choline borate (CB) ionic liquid was synthesized, characterized, and blended with a silicone liner (Molloplast-B) in concentrations of 1%, 2%, and 5% w/w to form the experimental group, CB, with three subgroups (CB1%, CB2%, and CB5%, respectively). Commercial silicone liners served as the negative control, while silicone liners blended with the antifungal drug itraconazole (1.25% wt/wt) were the positive control. The antifungal potential against Candida albicans was evaluated via a direct-contact assay, with growth inhibition quantified by measuring the culture turbidity (OD600). The tear strength was determined using the type A test and the Shore A hardness was measured using a durometer. A physical parameter, percent mass change (%), was tested using the immersion method (at 1 week and 6 weeks). The Alamar Blue assay was performed to assess the biocompatibility of the samples.

Data were statistically analyzed using SPSS 25, with p = <0.001. The results showed that CB1% had the most significant inhibitory effect on C. albicans growth (83.71%). The drug- incorporated liners gained the most weight (5.00 ± 0.11%). The liners in CB5% were the toughest, with a tear strength of 5.31 ± 1.84 kN/m. The liners in the negative control group (Molloplast-B) were the softest (Shore A = 60.16 ± 1.07), followed by those in CB5% (51.33 ± 1.40). The biocompatibility of the ionic liquid-modified samples was better than that of the positive controls.

The novel choline borate in silicone liners enhanced the antifungal potential and met the standard criteria of physical and mechanical compliance.