Desenvolvimento de um nanocompósito de resina acrílica autopolimerizável com nanotubos de haloisita carregados com clorexidina: síntese, caracterização e avaliação das propriedades antimicrobiana e físico-mecânica

• Autor(a) principal: Timbó, Isabelle da Costa Goes
• Data de Publicação: 2023
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Ceará (UFC)
• Texto Completo: http://www.repositorio.ufc.br/handle/riufc/71338
• topic: Candida albicans; Resinas acrílicas; Clorexidina; Nanotubos; Liberação Controlada de Fármacos; Streptococcus mutans

The incorporation of antimicrobials in dental materials has been investigated as a strategy for the prevention and treatment of oral conditions such as caries, periodontal diseases, and muco- sitis. The use of nanocarriers, such as halloysite nanotubes (HNT), has the potential to release drugs gradually and directly at the site of action. The aim of this study was to synthesize and characterize HNT loaded with chlorhexidine (CHX) and incorporate them into a self-curing acrylic resin (SAR), verifying the effects on the antimicrobial and physical-mechanical proper- ties of this material. The incorporation efficiency (IE) of CHX in nanotubes was calculated using data obtained by UV/vis spectrophotometer. The characterization of synthesized nano- material was performed by means of morphological evaluations, Fourier transforms infrared spectroscopy and thermal analyses. SAR disks were made with concentrations of 0, 3, 5, and 10% of the nanomaterial. To monitor CHX release, the specimens were immersed in deionized water at 37◦C (n=3) and spectral measurements were performed at predetermined times, ran- ging from 4 hours to 50 days. The antimicrobial activity was verified using the disk diffusion test in agar for Candida albicans (CA) and Streptococcus mutans (SM). The verification of Knoop microhardness and color change (n=9) were performed at baseline and after 30 days of immersion in distilled water. Finally, the surface topography was verified. Data were processed with SPSS software, using ANOVA/Bonferroni and paired t-test. The loading method obtained an IE of 8.15%. Samples with 10% showed gradual release throughout the observed period. Antimicrobial activity was verified for CA and SM, with no statistical differences between test groups. After 30 days of immersion, the 10% group showed a significant increase in surface hardness (p<0.05), and a progressive change in color (p<0.001) was also observed, within ac- ceptable standards, with increasing concentration of the nanomaterial. Modification of the SAR with HNT/CHX seems to be an advantageous approach, with the potential to obtain a sustained antimicrobial effect, without significantly compromising other physical-mechanical properties of the material.