OBJECTIVES The aim of this study was to investigate the effects of erosion and toothbrush abrasion on different restorative materials and human enamel. METHODS Human enamel and 5 kinds of tooth-colored restorative materials were used. The restorative materials included three composite resins (Filtek Silorane, Tetric EvoCeram, and Tetric EvoFlow), a polyacid-modified composite (Dyract Extra), ...

The installation procedures (which induce mechanical damage) and abrasion can cause unwanted changes on the properties of the geotextiles. In this work, a nonwoven polypropylene geotextile was subjected to three degradation tests: (1) mechanical damage, (2) abrasion and (3) mechanical damage followed by abrasion (successive exposure). The damage caused by the degradation tests was evaluated by ...

Abrasion of dental crown and the shape of denture occlusal surface are significant indicators in age determination of domestic mammals. The factors that significantly influence age determination of Eneolithic deer game in conditions of an open wildlife habitat are climatic changes that influenced their survival, as well as specific features of teeth morphological structure. In this paper the ag...

Second-order optical model solutions to the elastic scattering amplitude were used to evaluate total, absorption, and abrasion cross sections for neutron-nucleus scattering. Improved agreement with experimental data for total and absorption cross sections is found when compared with rst-order (coherent approximation) solutions, especially below several hundred MeV. At higher energies, the rstan...

Eroded enamel is more susceptible to abrasive wear than sound enamel. New toothpastes utilizing diamond particles as abrasives have been developed. The present study investigated the abrasive wear of eroded enamel by three commercially available toothpastes (one containing diamond particles) and compared it to the respective wear of sound enamel caused by these toothpastes. Seventy-two bovine e...

This study investigates preparation of melamine formaldehyde / montmorillonite nanocomposite coatings and evaluates its abrasion resistance property as a new material for wood based panel products. The ultrasonicated MF resin/clay blends with different clay loadings were applied in the form of coatings to the saturated decorative paper to prepare thermoset prepregs. Morphology and structure of ...

[1] Abrasion by bed load is a ubiquitous and sometimes dominant erosional mechanism for fluvial incision into bedrock. Here we develop a model for bedrock abrasion by saltating bed load wherein the wear rate depends linearly on the flux of impact kinetic energy normal to the bed and on the fraction of the bed that is not armored by transient deposits of alluvium. We assume that the extent of al...

OBJECTIVE This in situ study aimed to analyse the impact of different tetrafluorides (TiF(4), ZrF(4) and HfF(4)) and AmF on erosion and erosion plus abrasion of enamel and dentin. DESIGN Ten volunteers took part in this crossover and double-blind study performed in 8 phases of each 3 days. In each phase, 2 bovine enamel and 2 dentin specimens were fixed in intraoral appliances. One enamel and...

Air abrasion as a caries removal technique is less aggressive than conventional techniques and is compatible for use with adhesive restorative materials. Alumina, while being currently the most common abrasive used for cutting, has controversial health and safety issues and no remineralisation properties. The alternative, a bioactive glass, 45S5, has the advantage of promoting hard tissue remin...