Concrete Made with Dune Sand: Overview of Fresh, Mechanical and Durability Properties.

According to the authors' best information, the majority of research focuses on other waste materials, such as recycling industrial waste (glass, silica fume, marble and waste foundry sand), etc. However, some researchers suggest dune sand as an alternative material for concrete production, but knowledge is still scarce. Therefore, a comprehensive review is required on dune sand to evaluate its current progress as well as its effects on the strength and durability properties of concrete. The review presents detailed literature on dune sand in concrete. The important characteristics of concrete such as slump, compressive, flexural, cracking behaviors, density, water absorption and sulfate resistance were considered for analysis. Results indicate that dune sand can be used in concrete up to 40% without any negative effect on strength and durability. The negative impact of dune sand on strength and durability was due to poor grading and fineness, which restricts the complete (100%) substation of dune sand. Furthermore, a decrease in flowability was observed. Finally, the review highlights the research gap for future studies.

The Present State of the Use of Waste Wood Ash as an Eco-Efficient Construction Material: A Review.

A main global challenge is finding an alternative material for cement, which is a major source of pollution to the environment because it emits greenhouse gases. Investigators play a significant role in global waste disposal by developing appropriate methods for its effective utilization. Geopolymers are one of the best options for reusing all industrial wastes containing aluminosilicate and the best alternative materials for concrete applications. Waste wood ash (WWA) is used with other waste materials in geopolymer production and is found in pulp and paper, wood-burning industrial facilities, and wood-fired plants. On the other hand, the WWA manufacturing industry necessitates the acquisition of large tracts of land in rural areas, while some industries use incinerators to burn wood waste, which contributes to air pollution, a significant environmental problem. This review paper offers a comprehensive review of the current utilization of WWA with the partial replacement with other mineral materials, such as fly ash, as a base for geopolymer concrete and mortar production. A review of the usage of waste wood ash in the construction sector is offered, and development tendencies are assessed about mechanical, durability, and microstructural characteristics. The impacts of waste wood ash as a pozzolanic base for eco-concreting usages are summarized. According to the findings, incorporating WWA into concrete is useful to sustainable progress and waste reduction as the WWA mostly behaves as a filler in filling action and moderate amounts of WWA offer a fairly higher compressive strength to concrete. A detail study on the source of WWA on concrete mineralogy and properties must be performed to fill the potential research gap.

Effects of waste glass and waste marble on mechanical and durability performance of concrete.

Industrial waste has been rapidly increased day by day because of the fast-growing population which results environmental pollutions. It has been recommended that the disposal of industrial waste would be greatly reduced if it could be incorporated in concrete production. In cement concrete technology, there are many possibilities to use waste materials either as cement replacement or aggregate in concrete production. Two major industrials waste are glass and marble waste. The basic objective of this investigation is to examine the characteristics of concrete waste glass (WG) as binding material in proportions 10%, 20% and 30% by weight of cement. Furthermore, to obtain high strength concrete, waste marble in proportion of 40%, 50% and 60% by weight cement as fine aggregate were used as a filler material to fill the voids between concrete ingredients. Fresh properties were evaluated through slump cone test while mechanical performance was evaluated through compressive strength and split tensile strength which were performed after 7 days, 28 days and 56 days curing. Results show that, workability of concrete decreased with incorporation of waste glass and marble waste. Furthermore, mechanical performance improved considerably up 20% and 50% substitution of waste glass and waste marble respectively. Statistical approach of Response Surface Methodology (RSM) was used optimize both waste materials in concrete. Results indicate better agreement between statistical and experimental results.

Assessment of vertical ridge augmentation in anterior aesthetic zone using onlay xenografts with titanium mesh versus the inlay bone grafting technique: A randomized clinical trial.

The aim of this study was to evaluate the final vertical gain at the deficient anterior maxillary alveolar ridges using onlay bone grafts with titanium mesh versus inlay bone grafting. This was a single institutional randomized comparative clinical trial. The study population included 16 patients, with edentulous anterior maxillary alveolar ridges (40 implant sites) who were presented and treated at the Faculty of Oral and Dental Medicine in Cairo University from September 2013 to August 2015. Selected patients were randomly divided into two equal groups. The control group received onlay particulate xenograft together with titanium mesh as a space-maintaining device while the study group received inlay block xenograft (sandwich osteotomy) fixed with mini-plates. Assessment using cone beam computed tomography (CBCT) included the mean percentage of vertical gain at the proposed implant sites after 6 months taken from cross-sectional cuts. A total of 40 delayed implant placements were done. Results showed that there was no statistical significance between the two groups (P=0.2); the mean percentage of 6 months postoperative vertical bone gain in the control group was 20.7% and that in the study group was 31.6%.

In vitro anti-yeast activity of chloramphenicol: A preliminary report.

Chloramphenicol is a bacteriostatic antimicrobial agent but its antifungal activity is not known. The present study aimed to investigate the activity of chloramphenicol against 30 representative yeasts. The antimicrobial assay of chloramphenicol (50mg/mL; 100mg/mL and 200mg/mL) was determined by the disc diffusion method using Mueller-Hinton agar against 30 representative yeast strains. Zone of inhibition was read after 48-72h incubation at 37°C and results were compared with some standard antifungal agents. Most of the tested yeasts (73.3%) showed inhibition zones (5 up to 35mm) to chloramphenicol impregnated discs (200mg/mL). Three out of the four tested Candida albicans as well as Candida famata, Candida glabrata, Candida haemolonei and Cryptococcus neoformans showed no inhibition zones to chloramphenicol (200mg/mL). Caspofungin acetate (50mg/mL) inhibited 83.3% of the strains; ketoconazole (200mg/mL) 70% and metronidazole 10%. Chloramphenicol discs: 50 and 100mg/mL showed less activity (6.7% and 36.7%, respectively) compared to the 200mg discs; whereas chloramphenicol (BBL; 3µg/mL) inhibited 13.3% of the strains. The anti-yeast activities of chloramphenicol were comparable to other known antifungal compounds. Moreover, it is cheap, has fewer side effects and its inclusions in selective fungal media such as Mycosel have to be questioned.

Competent closure of chronic oroantral fistula with Zenoderm.

Ten patients suffered from chronic oroantral fistula had been closed with Zenoderm (lyophilized porcine dermis) covering the bony defects by 1-2 mm. The Zenoderm was covered by buccal sliding and rotating pedicle palatal flaps after complete resolution of sinusitis and/or infection of the fistula. In nine patients, competent closure of the fistula had been achieved also Zenoderm supported the flaps against negative or positive pressure from the sinus and supported the bony contour. In only one case the Zenoderm was expelled from the tissues due to infection which prevented healing of the flaps; this patient was controlled diabetic. The current study showed that Zenoderm had promising results in closing the chronic oroantral fistula.

Level of plasma proteins in patients with severe odontogenic infection and fever.

Twenty patients complaining of acute dental infection were admitted to the hospital. Clinical examination, peak of daily temperature for every patient were recorded. Electrophoretic studies of plasma proteins of all patients revealed slight increase of mean value of some plasma proteins (albumin, and gamma globulins) and more pronounced increase of mean values of alpha 1, and alpha 2 and beta globulins. The temperature and plasma proteins returned to normal levels after antibiotics therapy and dental treatment.

Carcinogenesis of mouse submandibular salivary gland using DMBA implant.

Carcinogenesis of 35 ddy male mice submandibular salivary glands were attempted; using implants of a 1 mg (2 mm) prepared pellets of the potent chemical carcinogen 9, 10-dimethyl-1, 2-benzanthracene (DMBA) dry powder without a vehicle or carrier. This method appeared to be easy, fast and effective. Within a period ranging from 7-14 weeks; twenty animals developed epidermoid carcinoma (two of them developed squamous cell carcinoma of covering skin as well), and two animals developed mixed tumors (pleomorphic adenoma like tumor) but neither adenocystic carcinoma nor sarcoma were found, the results were adequately discussed.

Comparative study of meniscus replacement using autogenous auricular cartilage versus Zenoderm.

Twelve adult mongrel dogs were divided into two groups and were used in this study; to compare and to evaluate histologically in 3 months period; unilateral replacement of the dogs meniscus of temporomandibular joint with either autogenous cartilage of their external ears or with Zenoderm heterogeneous graft. Autogenous cartilage of the dogs ear was progressively replaced by fibrous tissue and its attachment to the lateral pterygoid muscle was started at the third month postoperatively. On the other hand, Zenoderm was replaced by vascular fibrous tissue and begun to attach to the lateral pterygoid muscle from the first month postoperatively and showed also good functional adaptation to the bony surfaces. In both grafts there were no changes of the bone architecture.

Surgical correction of recurrent stenosed submandibular duct orifice.

Ten patients complaining of recurrent stone formation in submandibular stenosed duct orifice were diagnosed and evaluated. Surgical technique for removal of the stones and widening of the orifice to heal by secondary intention was discussed. Irrigation of the duct and wound with 5% diluted hydrogen peroxide was done to remove all desquamated epithelial cells and microliths to prevent narrowing the lumen of the duct. One year post operative follow up revealed no recurrence of stone formation in the submandibular duct and normal salivary flow for all patients.