Effects of incorporation of 2.5 and 5 wt% TiO₂nanotubes on fracture toughness, flexural strength, and microhardness of denture base poly methyl methacrylate (PMMA)

Abstract

PURPOSEThe aim of this preliminary study was to investigate, for the first time, the effects of addition of titania nanotubes (n-TiO2) to poly methyl methacrylate (PMMA) on mechanical properties of PMMA denture base.MATERIALS AND METHODSTiO2 nanotubes were prepared using alkaline hydrothermal process. Obtained nanotubes were assessed using FESEM-EDX, XRD, and FT-IR. For 3 experiments of this study (fracture toughness, three-point bending flexural strength, and Vickers microhardness), 135 specimens were prepared according to ISO 20795-1:2013 (n of each experiment=45). For each experiment, PMMA was mixed with 0% (control), 2.5 wt%, and 5 wt% nanotubes. From each TiO2:PMMA ratio, 15 specimens were fabricated for each experiment. Effects of n-TiO2 addition on 3 mechanical properties were assessed using Pearson, ANOVA, and Tukey tests.RESULTSSEM images of n-TiO2 exhibited the presence of elongated tubular structures. The XRD pattern of synthesized n-TiO2 represented the anatase crystal phase of TiO2. Moderate to very strong significant positive correlations were observed between the concentration of n-TiO2 and each of the 3 physicomechanical properties of PMMA (Pearson's P value ≤.001, correlation coefficient ranging between 0.5 and 0.9). Flexural strength and hardness values of specimens modified with both 2.5 and 5 wt% n-TiO2 were significantly higher than those of control (P≤.001). Fracture toughness of samples reinforced with 5 wt% n-TiO2 (but not those of 2.5% n-TiO2) was higher than control (P=.002).CONCLUSIONTitania nanotubes were successfully introduced for the first time as a means of enhancing the hardness, flexural strength, and fracture toughness of denture base PMMA.

Antimicrobial Activity of Thermocycled Polymethyl Methacrylate Resin Reinforced with Titanium Dioxide and Copper Oxide Nanoparticles

“…In this in vitro study, 150 heat-cured PMMA specimens (10 × 2 mm) were made with two different concentrations of TiO 2 and CuO nanoparticles as 2.5% TiO 2 , 2.5% CuO, 7.5% TiO 2 , 7.5% CuO, and control group (without nanoparticles) ( n = 30 per group). The concentrations of both nanoparticles were selected according to the previous studies [ 21 , 22 ] and the dimensions of the specimens for the antimicrobial test were based on the ISO standard #1567. To fabricate the PMMA specimens, 30 disk-shaped wax patterns (10 × 2 mm) were invested in dental stone (Fujirock EP; GC, Leuven, Belgium).…”

Prosthodontic Applications of Polymethyl Methacrylate (PMMA): An Update

“…Therefore, good mechanical properties are required for the functional performance of denture base materials (biofunctionality). Considering the significance of the mechanical properties, several modifications have been reported for various mechanical properties of PMMA, including its flexural strength [ 14 , 30 , 33 , 68 , 134 , 135 , 136 ], impact strength [ 14 , 137 , 138 , 139 , 140 ], fracture toughness [ 141 , 142 , 143 ], and surface hardness [ 67 , 98 , 141 , 144 , 145 ]. The flexural strength (also known as the modulus of rupture or transverse strength) is assessed using a 3-point bending test according to the guidelines of ISO 20795-1 [ 81 ].…”

“…Accordingly, cold-cured PMMA is favored for denture repair applications. Various modifications to PMMA materials can improve their strength for denture repair, with promising outcomes [ 31 , 68 , 141 , 142 ]. For example, the incorporation of ZrO 2 nanoparticles improved the flexural strength of PMMA repair materials [ 29 , 30 , 31 , 142 ].…”

Effect of novel cycloaliphatic comonomer on surface roughness and surface hardness of heat-cure denture base resin

“…Despite favorable characteristics of PMMA, the intended surface and mechanical properties have not been fulfilled. [ 7 ] Hence, there arises a necessity for improvising these properties of PMMA. Numerous methods and techniques have been experimented to ameliorate its properties by modifying the polymer with the incorporation of fibers and/or fillers.…”