Development of soft denture lining materials containing fluorinated monomers

Preparation and characterization of silane-modified SiO2 particles reinforced resin composites with fluorinated acrylate polymer

A series of fluorinated dental resin composites were prepared with two kinds of SiO₂ particles. Bis-GMA (bisphenol A-glycerolate dimethacrylate)/4-TF-PQEA (fluorinated acrylate monomer)/TEGDMA (triethylene glycol dimethacrylate) (40/30/30, wt/wt/wt) was introduced as resin matrix. SiO₂ nanopartices (30nm) and SiO₂ microparticles (0.3µm) were silanized with 3-methacryloxypropyl trimethoxysilane (γ-MPS) and used as fillers. After mixing the resin matrix with 0%, 10%, 20%, 30% SiO₂ nanopartices and 0%, 10%, 20%, 30%, 40%, 50% SiO₂ microparticles, respectively, the fluorinated resin composites were obtained. Properties including double bond conversion (DC), polymerization shrinkage (PS), water sorption (W_p), water solubility (W_y), mechanical properties and cytotoxicity were investigated in comparison with those of neat resin system. The results showed that, filler particles could improve the overall performance of resin composites, particularly in improving mechanical properties and reducing PS of composites along with the addition of filler loading. Compared to resin composites containing SiO₂ microparticles, SiO₂ nanoparticles resin composites had higher DC, higher mechanical properties, lower PS and lower W_p under the same filler content. Especially, 50% SiO₂ microparticles reinforced resins exhibited the best flexural strength (104.04 ± 7.40MPa), flexural modulus (5.62 ± 0.16GPa), vickers microhardness (37.34 ± 1.13 HV), compressive strength (301.54 ± 5.66MPa) and the lowest polymerization (3.42 ± 0.22%).

Influence of monomer content on the viscoelasticity, water sorption and solubility of experimental fluorinated soft lining materials

The influence of monomer content on the viscoelasticity, water sorption and solubility of experimental fluorinated soft lining materials was investigated. Changes in the viscoelastic properties of the materials were also examined after thermal cycling. Four fluorinated soft lining materials containing different amounts of methoxy diethylene glycol methacrylate (MDGMA) and tridecafluorooctyl methacrylate (13FMA) were prepared. The viscoelastic displacement for specimens containing 13FMA was found to be less than that without 13FMA (p<0.05), and the values tended to decrease with increasing 13FMA content. Reduction of the MDGMA content and addition of 13FMA caused a decrease of water sorption and solubility (p<0.05). Thermal cycling was found to affect the viscoelastic deformation of the specimens without 13FMA and those specimens with relatively large amounts of 13FMA.

Effect of composition of experimental fluorinated soft lining materials on bond strength to denture base resin

The purpose of the present study was to investigate the effect of the composition of experimental fluorinated soft lining materials on bond strength to denture base resin. Vinylidene fluoride/hexafluoro propylene copolymer (2-6F), tridecafluorooctyl methacrylate (13FMA), methoxy diethylene glycol methacrylate (MDGMA), and silica (as filler) were used for fabrication of the experimental soft lining materials. Nine experimental soft lining materials having various compositions of 2-6F, 13FMA, and MDGMA were prepared. Shear and tensile bond strength tests were performed before and after immersion in water. The water sorption for the materials was also measured. An increase in the content of acrylic monomer, MDGMA, in the experimental materials increased the bond strength before immersion in water but reduced the bond strength after immersion in water as compared to that before immersion in water. The inclusion of fluorinated monomer (13FMA) in the materials appeared to affect water sorption.

Basic evaluation on physical properties of experimental fluorinated soft lining materials

The purpose of the present study was to compare the properties required for the clinical application of soft lining materials containing a fluorinated monomer versus that of conventional materials in an effort to develop a new soft lining material with long-term stable viscoelastic properties. Four soft lining materials were examined. Two experimental materials containing dodecafluoroheptyl methacrylate (SR12F) or tridecafluorooctyl methacrylate (SR13F) were prepared. Two commercial soft lining materials, one acrylic-based and one silicone rubber-based, were selected as reference materials. Shore A hardness, viscoelastic properties, water sorption, solubility, and staining resistance were evaluated. The Shore A hardness and the displacements were analyzed with two-way analysis of variance (ANOVA) and Tukey's HSD test. The water sorption, the solubility and the color change were analyzed with one-way ANOVA and Tukey's HSD test. The significance level was set at 0.05. SR12F and SR13F showed greater viscous flow, low water sorption, low solubility, and good staining resistance compared to the commercial products. The results indicate that the soft lining materials containing fluorinated monomers might have a potentially long-term stable viscoelastic behavior.