Ionic liquid-loaded microcapsules doped into dental resin infiltrants

Marla Cuppini; Isadora Martini Garcia; Virgínia Serra de Souza; Kelly Cristine Zatta; Fernanda Visioli; Vicente Castelo Branco Leitune; Sílvia Stanisçuazki Guterres; Jackson Damiani Scholten; Fabrício Mezzomo Collares

doi:10.1016/j.bioactmat.2021.02.002

Ionic liquid-loaded microcapsules doped into dental resin infiltrants

Bioact Mater. 2021 Feb 12;6(9):2667-2675. doi: 10.1016/j.bioactmat.2021.02.002. eCollection 2021 Sep.

Authors

Marla Cuppini¹, Isadora Martini Garcia¹, Virgínia Serra de Souza², Kelly Cristine Zatta³, Fernanda Visioli⁴, Vicente Castelo Branco Leitune¹, Sílvia Stanisçuazki Guterres⁵, Jackson Damiani Scholten², Fabrício Mezzomo Collares¹

Affiliations

¹ Department of Dental Materials, School of Dentistry, Federal University of Rio Grande do Sul, Ramiro Barcelos Street, 2492, Rio Branco, 90035-003, Porto Alegre, RS, Brazil.
² Laboratory of Molecular Catalysis, Institute of Chemistry, Federal University of Rio Grande do Sul, Bento Gonçalves Avenue, 9500, Agronomia, 91501-970, Porto Alegre, RS, Brazil.
³ Cosmetology and Pharmaceutical Nanotechnology Laboratory, School of Pharmaceutical Sciences, Universidade Federal do Rio Grande do Sul, Av. Ipiranga 2752, 90610-000, Porto Alegre, RS, Brazil.
⁴ Oral Pathology Department, School of Dentistry, Federal University of Rio Grande do Sul, Rua Ramiro Barcelos, 2492, Rio Branco, 90035-003, Porto Alegre, RS, Brazil.
⁵ Cosmetology Laboratory, School of Pharmaceutical Sciences, Universidade Federal do Rio Grande do Sul, Av. Ipiranga 2752, 90610-000, Porto Alegre, RS, Brazil.

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.NTf₂) was synthesized. BMI.NTf₂ 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.

Keywords: Dental caries; Drug delivery systems; Mechanical; Polymers; Stress; Surface properties.