STATEMENT OF THE PROBLEM The mechanical and thermal properties of polymethyl methacrylate (PMMA) acrylic resin should be improved to counterweigh its structural deficiencies. PURPOSE The aim of this study was to compare the flexural strength and thermal conductivity of conventional acrylic resin and acrylic resin loaded with nanoclay. MATERIALS AND METHOD The methacrylate monomer containing...

PURPOSE This study aimed to measure the color change, surface roughness and flexural strength of heat-polymerized acrylic resin after its immersion in denture cleansers, simulating a 180-day use. METHODS Thirty disk-shaped (15mm x 4mm) and 30 rectangular samples (65mm x 10mm x 3.3mm) were prepared from heat-polymerized acrylic resin and immersed in Corega Tabs, Bony Plus, and distilled water....

BACKGROUND Finite element simulation has been used in last years for analysing the biomechanical performance of post-core restorations in endodontics, but results of these simulations have been interpreted in most of the works using von Mises stress criterion. However, the validity of this failure criterion for brittle materials, which are present in these restorations, is questionable. The obj...

The aim of this study was to assess the effect of adding nanoparticles to N1 acrylic resin intended for artificial sclera, in terms of the color stability, microhardness, and flexural strength of the resin. Three hundred samples of N1 acrylic resin were used: 100 samples for color stability and microhardness tests (each test was performed on the opposite side of each sample), and 200 samples fo...

Short randomly oriented banana and sisal hybrid fibre reinforced polyester composites, banana/polyester composites and sisal/polyester composites were fabricated at different fibre loading say, 0.20 to 0.50 Vf. Composites were prepared by varying the relative volume fraction of the two fibres at each fibre loading. When the fibre loading was increased; tensile, flexural and impact properties in...

OBJECTIVE Two visible light sources (tungsten-quartz-halogen and xenon-arc plasma) with vastly different intensities (200 and 1800 mW/cm(2)) but similar spectral outputs, were used to examine the effects of light intensity on conversion and flexural strength of a model dental resin formulation (75/25wt% bis-GMA/TEGDMA). METHODS The exact same polymer samples were used to correlate double bond...

The purpose of this study is to compare the flexural strength values of four different methods for chair side direct transfer methods of implant housing. Materials and Methods: Sixty heat-cured polymethylmethacrylate denture blocks were prepared of size 11 (±0.5) x 8 (±0.5) x 38(±0.5) mm. At the centre a hole of 5mmx8mm dimension was made to secure the implant housing.The Implant Housings were ...

The effect of organic phenol on the compressive and flexural strength of a metakaolin based geopolymer is studied. It was found that 12 wt% phenol resins can increase the compressive and flexural strength by 30% and 65% respectively. In addition, the reinforcing effect of phenol resin is higher in Na-PS and Na-PSS type geopolymers rather than Na-PSDS. Two distinct endothermic peaks were detecte...

OBJECTIVES To measure the flexural strengths and moduli of endodontic post materials and to assess the effect on the calculated flexural properties of varying the diameter/length (D/L) ratio of three-point bend test samples. METHODS Three-point bend testing of samples of 2mm diameter metal and fiber-reinforced composite (FRC) rods was carried out and the mechanical properties calculated at su...

sandwich panel with central core honeycomb aluminum as one of the main shielding structures because of their high strength-to-weight ratio and improved energy absorption capacity, has been attracted the attention of many researchers and practitioners in recent years. this paper initiates and presents a new type of central core honeycomb formed by hydroforming process. the study is augmented by ...