Improved mechanical performance of self-adhesive resin cement filled with hybrid nanofibers-embedded with niobium pentoxide

• Published in: Dental materials Vol. 35; no. 11; pp. e272 - e285
• Main Authors: Velo, Marilia M.A.C., Nascimento, Tatiana R.L., Scotti, Cassiana K., Bombonatti, Juliana F.S., Furuse, Adilson Y., Silva, Vinícius D., Simões, Thiago A., Medeiros, Eliton S., Blaker, Jonny J., Silikas, Nikolaos, Mondelli, Rafael F.L.
• Format: Journal Article
• Language: English
• Published: England Elsevier Inc 01.11.2019; Elsevier BV
• Subjects: Adhesion tests; Adhesives; Calorimetry; Cement; Chemical composition; Conversion; Cotton; Cotton-wool-like nanofibers; Dental Bonding; Dental cement; Dental Cements; Dental materials; Dental restorative materials; Dentistry; Differential scanning calorimetry; Fibers; Field emission microscopy; Fillers; Flexing; Fourier transforms; Hybrids; Infrared spectroscopy; Materials Testing; Mechanical properties; Microhardness; Modulus of rupture in bending; Morphology; Nanofibers; Niobium; Niobium oxides; Niobium pentoxide; Organic chemistry; Oxides; Physical properties; Resin cement; Resin Cements; Resins; Scanning electron microscopy; Silica; Silica gel; Silicon Dioxide; Sol-gel processes; Solution blow spinning; Spectrum analysis; Spinning (materials); Surface Properties; Thermal properties; Thermodynamic properties; Variance analysis; Wool; X-ray spectroscopy; Resin cement; Mechanical properties; Hybrids; Cotton-wool-like nanofibers; Solution blow spinning; Niobium pentoxide
• ISSN: 0109-5641; 1879-0097
• DOI: 10.1016/j.dental.2019.08.102

•Hybrid-fibers (inorganic-organic) are potential reinforcement for dental materials.•Niobium is promising as filler into fibers to improve mechanical properties.•SBS method fabricates non-woven fibers with small diameters in a rapid technology. In this study hybrid nanofibers embedded with niobium pentoxide (Nb2O5) were synthesized, incorporated in self-adhesive resin cement, and their influence on physical-properties was evaluated. Poly(D,L-lactide), PDLLA cotton-wool-like nanofibers with and without silica-based sol–gel precursors were formulated and spun into submicron fibers via solution blow spinning, a rapid fiber forming technology. The morphology, chemical composition and thermal properties of the spun fibers were characterized by field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS) and Fourier-transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC), respectively. Produced fibers were combined with a self-adhesive resin cement (RelyX U200, 3M ESPE) in four formulations: (1) U200 resin cement (control); (2) U200+1wt.% PDLLA fibers; (3) U200+1wt.% Nb2O5-filled PDLLA composite fibers and (4) U200+1wt.% Nb2O5/SiO2-filled PDLLA inorganic–organic hybrid fibers. Physical properties were assessed in flexure by 3-point bending (n=10), Knoop microhardness (n=5) and degree of conversion (n=3). Data were analyzed with One-way ANOVA and Tukey’s HSD (α=5%). Composite fibers formed of PDLLA-Nb2O5 exhibited an average diameter of ∼250nm, and hybrid PDLLA+Nb2O5/SiO2 fibers were slightly larger, ∼300nm in diameter. There were significant differences among formulations for hardness and flexural strength (p<0.05). Degree of conversion of resin cement was not affected for all groups, except for Group 4 (p<0.05). Hybrid reinforcement nanofibers are promising as fillers for dental materials. The self-adhesive resin cement with PDLLA+Nb2O5 and PDLLA+Nb2O5/SiO2 presented superior mechanical performance than the control group.