The evaluation of some flexural properties of a denture base resin reinforced with various aesthetic fibers

This study was performed to determine whether some flexural properties of a denture base resin material could be improved through reinforcement with five types of aesthetic fibers at 3% concentration by weight and in 2, 4, and 6 mm length. Five specimens of similar dimensions were prepared for each of the test groups; base resin and the same resin with glass, rayon, polyester, nylon 6 and nylon 6,6 fibers in three different lengths. Flexural properties were evaluated by using a 3-point bending test. A visual examination was also made to determine mode of fracture of the specimens. The incorporation of different fibers in varying lengths had no significant effect on flexural strength of the resin. The specimens reinforced with nylon 6,6 fibers of 6 mm length showed the highest flexural strength. Young's modulus and maximum load suggests that such reinforcement makes resin resistant to fracture

Tensile Bond Strength of a Highly Cross-Linked Denture Tooth to the Compression-Molded and Injection-Molded Denture Base Polymers

This study compared tensile bond strengths between conventional compression-molded heat (HC)-, auto (AP)-, and microwave-polymerized (MC) poly(methyl methacrylate)-based denture resins and a relatively new injection-molded, microwave-polymerized polyurethane based resin (MI) bonded to a highly cross-linked denture tooth. In the first part of the experiments, denture teeth were used as received. In the second part, they were treated with dichloromethane to see its effect on bonding of conventional denture bases (HCS and APS). Bond strength was tested in tension according to ADA specification No.15. The results showed that the HC group failed cohesively because of higher interface bonding (49.95MPa) compared with those of the others (AP: 25.41MPa; MC: 22.06MPa; MI: 20.02MPa). The application of dichloromethane improved bond strengths of HCS and APS groups (60.61 and 32.03MPa, respectively). It was suggested that dichloromethane could be applied on the denture teeth ridge lap area prior to denture base processing to enhance adhesion between the tooth/resin

Effect of Maleic Anhydride Pretreatment on Tensile Bond Strength of a Silicone Soft Liner to a Denture Base Polymer

Purpose: To determine the effect of resin surface treatment with dissolved maleic anhydride in butanone added into primer on the tensile bond strength between an acrylic denture base resin and a silicone soft liner

Effects of Different Denture Cleansers on the Tensile Bond Strength of Denture Liners

The effect of two denture cleansers (Polident (R) and Protefix (R)) on the tensile bond strength between four soft liner materials (Molloplast B (R), Permaflex (R), Sofreliner Tough Medium (R), and GC Reline Soft (R)) and a conventional denture base resin was investigated. For each of the liner materials 35 test specimens were prepared according to test the requirements and assigned into seven groups (n=5). Before tensile testing, five of the liner specimens were kept in water or soaked in two cleansing solutions during 2 and 7 d. Five other samples served as a control group subjected directly to tensile testing. The bond strength values were obtained using a universal testing machine and compared statistically. The type of failure was assessed visually. No significant difference was found between the groups for the tested conditions used (p0.05). The most frequent failure mode was cohesive for Molloplast and Permaflex specimens, adhesive for Sofreliner Tough Medium, and a mixed type of failure was observed for GC Reline Soft material

Peel Bond Strength of Two Silicone Soft Liners to a Heat-cured Denture Base Resin

Purpose: This study investigated the peel strength of two different soft liners to a polymethylmethacrylate (PMMA) denture base resin before and after thermocycling

The Effect of Surface Treatments on Tensile Bond Strength between a Silicone Soft Liner and a Heat-Cured Denture Base Resin

This study evaluated tensile bond strength of a denture soft lining material to a poly (methylmethacrylate) (PMMA) denture base resin subjected to different surface treatment modalities and thermocycling. The materials tested were a silicone-based liner, Molloplast B (R), and a heat-cured denture base resin, Meliodent (TM). The denture soft lining material was packed against cured PMMA base resin, which was smoothed; sandblasted with 250-mu m Al2O3 particles; or lased with a KTP laser; or against uncured PMMA dough (n = 10). In each group, five specimens were thermocycled in a water bath (5-55 degrees C; 3000 cycles) before testing, whereas the other five were directly tested after 24 h. A tensile test was performed using a universal testing machine. Data showed that different treatment modalities of resin surfaces affected adhesion between these two materials and the highest bond values were recorded for cured/smoothed samples under each condition tested. Thermocycling of specimens had no significant reducing effect on measured bond strength values