Micro Shear Bond Strength between Glass Ionomer and Calcium Silicate Cements to Dentine: In Vitro Comparative Study

The research aims to evaluate the micro shear bond strength of the calcium silicate cement (Biodentine) and the glass ionomer cement (GIC) to dentine. The study was performed using upper or lower premolars, and samples were divided into six equal subgroups according to the time period (3 h, 1 day, 1 week, 2 weeks, 4 weeks, 8 weeks), in order to study changes in the values of shear bond strength with time. The comparative study showed that the success rate of adhesion in the Biodentine group was smaller than that in the GIC group for the tested premolars after 3 hours and one day, whereas the success rate in the Biodentine group was greater than that in the GIC group for the tested premolars after 8 weeks. Results showed a positive correlation between the mean values of shear bond strengths and the studied time in Biodentine group, which ranged from 1.49 ± 0.18 MPa at 3 hours to a maximum value of 2.65 ± 0.26 MPa after 8 weeks. While there was a negative correlation between the mean values and the studied time in the GIC group and values ranged from 3.02 ± 0.13 MPa at 3 hours and 2.06 ± 0.09 MPa at 8 weeks. The study showed the advantage of Biodentine compared with GIC in terms of micro-bonding to dentine, which can have a clinically significant importance in preventing the micro leakage and reducing bacterial contamination.

The effect of ceramic primer on Bond strength of resin cement to zirconia ceramic

The purpose of this in vitro study to evaluate the effect of ceramic primer on the bond strength of adhesive resin cement to zirconia ceramic surface.

دراسة تأثير الاضافة المشتركة للغضار السوري و أوكسيد المغنيزيوم على مرونة الحجر الإسمنتي

The study of the effect of the common addition of Syrian Clay and magnesium oxides on the specifications of the resulting cement stone and specifically its effect on the elasticity of the resulting stone.

An In Vitro Comparative Study On The Effect Of Different Etching Systems On Bonding Strength Of Giomer To Conventional Glass Ionomer Cement

An appropriate bond between glass‑ionomer and the superficial resin materials is very important for the success of sandwich technique. The aim of the present in vitro study was to evaluate the effect of three surface treatments of conventional glass‑ionomer on its shear bond strength to giomer

Influence of water to cement ratio on the attenuation of ionizing radiation and speed of Ultrasonic in ordinary concrete when change of temperatures

Five mixtures of ordinary concrete of dolomite aggregates were prepared by changing the water to cement ratio. Thirty six cubic concrete samples were prepared for every mixture.

Mechanical strength development of binary and ternary blended cement mortars containing natural pozzolans and limestone powder

According to the Syrian standard 3411 & European standard EN 197-1, Portland pozzolana cements and Portland limestone cements can be produced by partial replacement of pozzolan or limestone up to 35%. Despite of the economical, ecological and technical benefits of adding natural pozzolan and limestone powder, they are often associated with shortcomings. The objective of the study is to investigate the effect of adding natural pozzolan, limestone powder or both on the mechanical strength development of the prepared cement mortars. In the study, sixteen types of binders (one OPC, six binary and nine ternary blended cements) with different replacement levels of natural pozzolan, limestone powder or both have been produced. The development of the compressive and flexural tensile strength of all mortar specimens has been investigated after 2,7,28 & 90 days curing, respectively. Test results revealed that there was a decrease in strength with increasing amounts of natural pozzolan. In addition, there was found an increase in the early age strength with adding limestone powder. The increase in compressive strength when adding both natural pozzolan and limestone powder has also been noted. Further, based on the results obtained, an empirical equation was derived to predict the mechanical strengths of binary & ternary blended cement mortars with curing times. The influence of adding natural pozzolan, limestone powder or both on some physical properties of binary and ternary blended cements have been reported, as well.

Reduction of Vertical Raw Mill Vibration Effect on control Instruments beam in New Hama Cement Factory By Tuned Mass ى Damper ى(TMD)

This research drives at studying the reduction of vibration effect on central control system located on about 100 m of the Vertical mill running at New Hama Cement factory , which grinds raw materials necessary for cement production ,Whereas , the increase of vibration intensity leads to vibrate control Instruments beams and the electronic elements will be damaged.

Calculating Emissions Of Carbon Dioxide Resulting From Tartous Cement Company

The aim of research is to calculate the emissions of carbon dioxide (CO2) generated by the cement industry (Tartous Cement Company as a case study), depending on the standards and principles set by the World Resources Institute protocol (WRI) and the World Business Council for Sustainable Development Protocol (WBCSD 2011), in addition to standards and guidelines developed by the Intergovernmental Panel on Climate Change (IPCC 2007).

IN Vitro Study for fluoride release evaluation by restorative materials

Objective:This study evaluated the fluoride release of four dental restorative materials for a period of 28 days. Materials And Methods:A total of 10 specimens (4 * 2 * 2)mm3 for each of the four materials were prepared following manufacturer’s instructions and immersed independently in 2 ml of distilled water which was changed every period for all the specimens. Results:The results demonstrated that the glass ionomer cements (Fuji IX GP and VivaglassCem) release high fluoride compared with the compomer and composite resin, but rapidly decreased after the third day and continued this releasing for a period of 28 days , also showed low fluoride release of composite resin and lacking entirely with the passage of time. Conclusions:The fluoride released by the glass ionomer cements (GICs) was found to be highest during the first 24 h and decreased significantly over the 1st week with lower levels obtained on the 28th day, thus demonstrating the phenomenon of “initial burst”. The composite resin and compomer used in this study did not show this “initial burst”.

Effect of metal type and surface treatment on shear bond strength of resin cement (in vitro study)

Background Resin bonded fixed partial dentures appeared to prevent the excessive preparation of dental tissue Investigation of surface treatments to improve the bond of resin cements to metals may contribute to the longevity of these restorations. Due to the potential lack of ideal preparation form the type of alloy and its surface pretreatment may have clinically relevant correlations with the retentive strength of castings to minimally retentive preparations Aim The aim of this search is to study the bonding resin cement strength to different types of the metal alloy due to the surface treatment Purpose Evaluate the effects of two different surface treatments on shear bond strength SBS between a palladium silver alloy Pb Ag and commercially pure titanium CP Ti cast alloy with resin luting cements