Nanogel termorresponsivo carregado com ibuprofeno aplicado como agente anti-inflamatório no clareamento dental: um estudo in vivo

Abstract

The in vivo ability of thermosensitive nanogel containing ibuprofen for bioadhesion on the surface of teeth submitted to bleaching and drug delivery through dentinal tubules to the dental pulp were evaluated in Wistar rats. Drug-loaded selfassembled oil in water nanoemulsions presented droplet size < 150 nm and negative zeta potential. Nanoemulsions containing poloxamer 407 in the aqueous phase exhibited reduced droplet size, improved physical stability, controlled the thermosensitive viscosity, and slow drug release. Different treated animals’ groups included a control group (CTRL); bleached animals (BLE) (37.5% H2O2, Pola Office Plus®, SDI); bleached animals treated with a conventional ibuprofen-loaded hydrogel (BLE+IBF-GEL), and bleached animals treated with thermosensitive ibuprofenloaded nanogel (BLE+IBF-NEG). Compared to the BLE+IBF-GEL group, scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) images showed the superior ability of BLE+IBF-NEG group to offer a physical barrier on the tooth surface, pores occlusion, and transport the fluorescent dye rhodamine B to dental pulp. Morphological analysis revealed the lowest inflammatory infiltrate scores and absence of necrosis for BLE+IBF-NEG group after 24 hours and 14 days. Immunohistochemical studies reinforced this hypothesis. The experimental data presented in this study confirm the incredible potential for topical and easy application of a novel and smart nanogel, as analgesic and anti-inflammatory treatment for bleaching procedure. The multidisciplinary nature of the study enabled its development and improvement of the results obtained.