Effect of the addition of functionalized TiO2 nanotubes and nanoparticles on properties of experimental resin composites

Author(s)

de Freitas Guimaraes, Genine Moreira ^[1] ; Bronze-Uhle, Erika Soares ^[1] ; Lisboa-Filho, Paulo Noronha ^[2] ; Piovezan Fugolin, Ana Paula ^[3] ; Sanches Borges, Ana Flavia ^[1] ; Gonzaga, Carla Castiglia ^[4] ; Pfeifer, Carmem Silvia ^[3] ; Furuse, Adilson Yoshio ^[1]

Affiliation

^[1] Univ Sao Paulo, Bauru Sch Dent, Dept Operat Dent Endodont & Dent Mat, Bauru, SP - Brazil

^[2] State Univ Sao Paulo, Fac Sci, Dept Phys, Bauru, SP - Brazil

^[3] Oregon Hlth & Sci Univ, Dept Restorat Dent, Div Biomat & Biomech, Portland, OR 97201 - USA

^[4] Posit Univ Curitiba, Sch Hlth Sci, Grad Program Dent, Curitiba, Parana - Brazil

• Document type: Journal article
• Source: Dental Materials; v. 36, n. 12, p. 1544-1556, DEC 2020.
• Web of Science Citations: 0

Abstract

Objective. To evaluate the influence of the addition of functionalized and non-functionalized TiO2 nanostructures on properties of a resin composite. Methods. TiO2 nanostructures were synthesized and functionalized, using 3(aminopropyl)triethoxysilane (APTMS) and 3-(trimethoxysilyl)propyl methacrylate (TSMPM). Characterizations were performed with XRD, EDS, TEM, and TGA. Resin composites containing Bis-GMA/TEGDMA, CQ, DABE, and barium-aluminum silicate glass were produced according to TiO2 nanostructure (nanotube or nanoparticle), concentration (0.3 or 0.9 wt%), and functionalization (APTMS or TSMPM). The resin composite without nanostructures was used as control. The amount of fillers was kept constant at 78.3 wt% for all materials. The degree of conversion (DC at 0 h and 24 h), maximum polymerization rate (Rp(max)), and Knoop microhardness (KHN before and after ethanol softening) were evaluated. Data were analyzed with two-way ANOVA with repeated measures and Tukey's HSD (a = 0.05). Results. TGA results demonstrated that functionalizations were effective for both nanostructures. For DC, resin composites, time and interaction effect were significant (p < 0.001). Higher DC was found for 0.3-wt%-functionalized-nanotubes at 24 h. For nanoparticles, only 0.9-wt%-non-functionalized and 0.3-wt%-APTMS-functionalized showed DC similar to the control and all other groups showed higher DC (p < 0.05). Rpmax was higher for 0.3-wt%APTMS-nanotubes, which corresponded to higher DC after 24 h. The lowest Rpmax occurred for 0.9-wt%-TSMPM-nanotubes, which showed smaller DC at 0 h. For KHN, resin composites, ethanol softening and interaction effect were significant (p < 0.001). KHN decreased after ethanol softening all groups, except for 0.3-wt%-TSMPM-nanotubes, 0.9-wt%-TSMPMnanotubes, and 0.3-wt%-non-functionalized-nanoparticles. Conclusion. The resin with 0.3-wt%-TSMPM-nanotubes showed higher DC after 24 h, while being the most stable material after the ethanol softening. Significance. The addition of functionalized TiO2 nanostructures in resin-based materials may improve the properties of the material. (C) 2020 The Academy of Dental Materials. Published by Elsevier Inc. All rights reserved. (AU)

• FAPESP's process: 19/05427-9 - Dental adhesives modified by TiO2 nanotubes as carriers of enzyme inhibitors: synthesis, functionalization and incorporation of nanotubes and evaluation of enzymatic activity physico-chemical, mechanical and biological properties
• Grantee: Adilson Yoshio Furuse
• Support Opportunities: Regular Research Grants
• FAPESP's process: 17/23331-3 - Influence of concentration and functionalization of nanotubes and nanoparticles of TiO2 in the properties of experimental resins
• Grantee: Genine Moreira de Freitas Guimarães
• Support Opportunities: Scholarships in Brazil - Master