The objective of this study was to compare the abrasion resistance, resistance to penetration, and mode of deformation of a filled (A*) and two unfilled (Bt and C$) pit and fissure sealants. Samples were mixed following manufacturers' instructions and stored at 37 C for 24 hours before testing. Five cylindrical samples of each sealant were abraded on silicon carbide paper§ with continuous flush...

Brushing is the most common cleansing method employed on complete dentures and it may damage the integrity of acrylic resin, the main component of this type of prosthesis. This study evaluated the abrasion resistance of artificial teeth with different number of acrylic layers, and the abrasiveness of specific and non-specific dentifrices for denture cleaning. The abrasion test was conducted by ...

This paper deals with the state-of-the-art information on high-calcium, ASTM Class C fly ash use in cement-based construction materials, such as high-performance concrete, ready-mixed concrete, etc. The major topics included are: properties of fly ash, effects of fly ash inclusion on fresh and hardened concrete, and future research needs. The fresh concrete properties include workability, water...

Abstract There are situations where parts manufactured by 3D printing processes must have a high abrasion resistance. To conduct experimental research on this subject, relatively simple test equipment for abrasive wear of pin-on-disk type was designed and materialized. The pieces from the material were pressed with known forces surface rotating paper disk. made polyethylene terephthalate PET ca...

Cadmium has been identified as a threat to worker health and the environment. A test program was conducted to evaluate the performance of environmentally acceptable substitutes for cadmium plating. Fifteen test coatings were exposed to natural marine, industrial, and rural atmospheres for 12 -months. Additional laboratory tests were conducted to determine coating abrasion resistance, adhesion, ...