Ionic liquid-loaded microcapsules doped into dental resin infiltrants

Abstract

Resin infiltrants have been effectively applied in dentistry to manage non-cavitated carious lesions in proximal dental surfaces. However, the common formulations are composed of inert methacrylate monomers. In this study, we developed a novel resin infiltrant with microcapsules loaded with an ionic liquid (MC-IL), and analyzed the physical properties and cytotoxicity of the dental resin. First, the ionic liquid 1- n -butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (BMI.NTf 2 ) was synthesized. BMI.NTf 2 has previously shown antibacterial activity in a dental resin. Then, MC-IL were synthesized by the deposition of a preformed polymer. The MC-IL were analyzed for particle size and de-agglomeration effect via laser diffraction analysis and shape via scanning electron microscopy (SEM). The infiltrants were formulated, and the MC-IL were incorporated at 2.5%, 5%, and 10 wt%. A group without MC-IL was used as a control. The infiltrants were evaluated for ultimate tensile strength (UTS), contact angle, surface free energy (SFE), and cytotoxicity. The MC-IL showed a mean particle size of 1.64 (±0.08) μm, shriveled aspect, and a de-agglomeration profile suggestive of nanoparticles' presence in the synthesized powder. There were no differences in UTS among groups (p > 0.05). The incorporation of 10 wt% of MC-IL increased the contact angle (p < 0.05), while the addition from 5 wt% reduced the SFE in comparison to the control group (p < 0.05). The human cell viability was above 90% for all groups (p > 0.05). The incorporation of microcapsules as a drug-delivery system for ionic liquids may be a promising strategy to improve dental restorative materials.

Novel dental resin infiltrant containing smart monomer dodecylmethylaminoethyl methacrylate

“…To give the material antibacterial properties, researchers added antibacterial agents into resin infiltrant. Several studies modified the materials with AgNP ( Kielbassa et al., 2020 ), quaternary ammonium methacrylate ( Yu et al., 2020 ), ionic liquid ( Cuppini et al., 2021 ), etc., which has potential results. But they had the same limitation, that is killing all the bacteria instead of showing an antibacterial effect only during microdysbiosis.…”

“…During the development of caries, oral microbial diversity is decreased, and the acidogenic bacteria can multiply and produce acids, causing the pH to decrease and leading to hard tissue demineralization ( Selwitz et al., 2007 ). Antibacterial agents such as silver nanoparticles (AgNP) ( Kielbassa et al., 2020 ; Li et al., 2020 ), quaternary ammonium methacrylate ( Yu et al., 2020 ), and ionic liquid-loaded microcapsules ( Cuppini et al., 2021 ) were incorporating into dental materials to inhibit the growth of plaque. However, oral commensal microbiome colonizes on dental tissue plays an essential role in oral microecology ( Rosier et al., 2018 ).…”

Resin Infiltration of Non-Cavitated Enamel Lesions in Paediatric Dentistry: A Narrative Review

“…Apart from that, the effects of the incorporation of antibacterial agents as fillers on the mechanical properties and caries arrest ability of the RI also have been reported in the literature [ 97 , 131 , 132 , 133 , 134 , 135 , 136 ]. Kielbassa et al [ 97 ] investigated the effectiveness and penetration ability of silver-enhanced RI.…”

“…Another innovative antibacterial infiltrant was described by Cuppini et al [ 135 ]. They used the ionic liquid 1-n-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (BMI.NTf 2 ) encapsulated with methacrylate-based microcapsules as the RI fillers.…”

Strategies toward development of antimicrobial biomaterials for dental healthcare applications

“…Encapsulation of ILs will be an ideal strategy to gain control over release of antimicrobials over longer periods. Recently, Cuppini et al (2021) incorporated IL 1‐ n ‐butyl‐3‐methylimidazolium bis(trifluoromethanesulfonyl)imide in the form of microcapsule in resin infiltrant. However, ILs are not without disadvantages.…”