background: scuba diving is one of the fastest growing sports in the world. the objective of this study was to evaluate the effect of pressure variations to which divers are exposed on the pull out strength of glass fiber post luted with different cements. materials and methods: in this in vitro study, 120 extracted, single-rooted lower premolars were endodontically treated. they were randomly ...

The recovery behavior for strength and impermeability of cementitious composites embedded with organic microcapsules was investigated in this study. Mortar specimens were formed by mixing the organic microcapsules and a catalyst with cement and sand. The mechanical behaviors of flexural and compression strength were tested. The results showed that strength could increase by up to nine percent w...

In this study, the effect of cement content on concrete performance in corrosive environments is investigated on concrete mixtures having the same water/cement (w/c) ratio. Three w/c ratios (0.40, 0.45 and 0.50) were used and for each w/c ratio three mixtures were prepared with cement contents 350, 400 and 450 kg/m3. The compressive strength, electrical resistivity and chloride diffusivity of t...

Nano-TiO2 (NT) and nano-SiO2 (NS) were separately added in the cement paste to investigate the rheological property of fresh mixtures and mechanical strength in hardened state. The effects of different dosages and types of nano-particles on the properties of cement paste were studied. The results indicated that the rheological behavior of the fresh cement paste coincides with the Modified Bingh...

Introduction Cement is the most abundantly used man made material on the planet, accounting for a 40 Billion USD market in the US alone [1]. Widespread use of cement includes applications in oil well casings, roadways, buildings, and even as a bone graft technology for the treatment of osteoporosis[2,3]. As cements role as the foundation of our infrastructure broadens, demand for higher strengt...

Background and Aim: Debonding is the most commonly encountered failure in teeth restored with fiber posts that mainly occurs at the weakest interface (dentin-cement interface). Thus, reinforcement of this interface is mandatory. The aim of this study was to evaluate the effect of different root dentin surface treatments after post space preparation on bond strength of fiber posts cemented with ...

Synopsis-In this research, possible usage of EAF dust on cement is investigated. Therefore, effects of addition of different percentages of EAF dust on the most important properties of cement such as hydration heat, water coefficient, viscosity, initial and final setting times, strength development and leachability of heavy metals were studied. Results showed that EAF dust alters the characteri...

Introduction: Retention of fiber reinforced composite posts depends on the bond strength between post and cement, and cement and root dentin. The aim of this study is to evaluate the bond strength of one type of fiber post to radicular dentin with different adhesive cements. Materials and Methods: Crowns of 44 caries-free, human premolar were removed 2 mm below the CEJ and the roots were endod...

this research paper presents the use of wasteful supplementary cementitious materials like fly ash and silica fume to conserve the cement used in concrete. the cement industry is one of the major producers of greenhouse gases and an energy user. in this study, portland cement was used as a basic cementitious material. fly ash and silica fume were used as the cement replacements by weight. the r...

in this study, the effect of cement content on concrete performance in corrosive environments is investigated on concrete mixtures having the same water/cement (w/c) ratio. three w/c ratios (0.40, 0.45 and 0.50) were used and for each w/c ratio three mixtures were prepared with cement contents 350, 400 and 450 kg/m3. the compressive strength, electrical resistivity and chloride diffusivity of t...