681 research outputs found

    Endodontic treatment of trauma-induced necrotic immature teeth using a tricalcium silicate-based bioactive cement : a report of 3 cases with 24-month follow-up

    No full text
    Background: Pulp necrosis is the second most common complication after traumatic dental injuries and occurs mostly within the first 6-24 months of follow-up period, depending on the type of dental trauma. Case report: Three cases with endodontic treatment scenarios of trauma-induced necrosis in immature permanent anterior teeth. All cases were treated by full canal obturation with Biodentine (Septodont, Saint Maur des Fosses, France) and documented for a follow-up period of 24 months. Conclusion: Copious irrigation of the root canal, minimal mechanical preparation, use of calcium hydroxide for a short period of time and complete obturation of these immature teeth with a bioactive cement with superior mechanical properties such as Biodentine were the prominent reasons attributed to the success of these three cases

    SCN9A channelopathy associated autosomal recessive Congenital Indifference to Pain : a case report

    No full text
    Background: Congenital Indifference to Pain (CIP) is a rare condition that inhibits the ability of patients to perceive physical pain but otherwise keeps normal sensory modalities. The condition has been mapped to an autosomal recessive trait to chromosome 2q 24.3 with mutations on the SCN9A gene. Case report: A 2 year old Caucasian female presented with CIP. Bite injuries, tongue wounds and unaccounted dental trauma episodes were frequently reported. Preventive instructions and possible treatment modalities were discussed with the parents. Conclusion: The cornerstone of treating CIP patients is an extensive preventive approach alongside regular oral examination at home by parents as well as routine recall appointments with dentists

    Effect of exposed surface area, volume and environmental pH on the calcium ion release of three commercially available tricalcium silicate based dental cements

    Get PDF
    Tricalcium silicate cements (TSC) are used in dental traumatology and endodontics for their bioactivity which is mostly attributed to formation of calcium hydroxide during TSC hydration and its subsequent release of calcium and hydroxide ions. The aim of this study was to determine the effect of volume (Vol), exposed surface area (ESA) and pH of surrounding medium on calcium ion release. Three commercially available hydraulic alkaline dental cements were mixed and condensed into cylindrical tubes of varying length and diameter (n = 6/group). For the effect of ESA and Vol, tubes were immersed in 10 mL of deionized water. To analyze the effect of environmental pH, the tubes were randomly immersed in 10 mL of buffer solutions with varying pH (10.4, 7.4 or 4.4). The solutions were collected and renewed at various time intervals. pH and/or calcium ion release was measured using a pH glass electrode and atomic absorption spectrophotometer respectively. The change of pH, short-term calcium ion release and rate at which calcium ion release reaches maximum were dependent on ESA (p < 0.05) while maximum calcium ion release was dependent on Vol of TSC (p < 0.05). Maximum calcium ion release was significantly higher in acidic solution followed by neutral and alkaline solution (p < 0.05)

    A perovskite oxide with high conductivities in both air and reducing atmosphere for use as electrode for solid oxide fuel cells

    Get PDF
    Electrode materials which exhibit high conductivities in both oxidising and reducing atmospheres are in high demand for solid oxide fuel cells (SOFCs) and solid oxide electrolytic cells (SOECs). In this paper, we investigated Cu-doped SrFe0.9Nb0.1O3−δ finding that the primitive perovskite oxide SrFe0.8Cu0.1Nb0.1O3−δ (SFCN) exhibits a conductivity of 63 Scm−1and 60 Scm−1 at 415 °C in air and 5%H2/Ar respectively. It is believed that the high conductivity in 5%H2/Ar is related to the exsolved Fe (or FeCu alloy) on exposure to a reducing atmosphere. To the best of our knowledge, the conductivity of SrFe0.8Cu0.1Nb0.1O3−δ in a reducing atmosphere is the highest of all reported oxides which also exhibit a high conductivity in air. Fuel cell performance using SrFe0.8Cu0.1Nb0.1O3−δ as the anode, (Y2O3)0.08(ZrO2)0.92 as the electrolyte and La0.8Sr0.2FeO3−δ as the cathode achieved a power density of 423 mWcm−2 at 700 °C indicating that SFCN is a promising anode for SOFCs

    Scandium Doping Effect on a Layered Perovskite Cathode for Low-Temperature Solid Oxide Fuel Cells (LT-SOFCs)

    Get PDF
    Layered perovskite oxides are considered as promising cathode materials for the solid oxide fuel cell (SOFC) due to their high electronic/ionic conductivity and fast oxygen kinetics at low temperature. Many researchers have focused on further improving the electrochemical performance of the layered perovskite material by doping various metal ions into the B-site. Herein, we report that Sc3+ doping into the layered perovskite material, PrBaCo2O5+ (PBCO), shows a positive effect of increasing electrochemical performances. We confirmed that Sc3+ doping could provide a favorable crystalline structure of layered perovskite for oxygen ion transfer in the lattice with improved Gold-schmidt tolerance factor and specific free volume. Consequently, the Sc3+ doped PBCO exhibits a maximum power density of 0.73 W cm(-2) at 500 degrees C, 1.3 times higher than that of PBCO. These results indicate that Sc3+ doping could effectively improve the electrochemical properties of the layered perovskite material, PBCO

    Electrochemical performance of YST infiltrated and fe doped YST infiltrated YSZ anodes for IT-SOFC

    Get PDF
    Donor doped and donor-acceptor co-doped strontium titanate perovskite are investigated for intermediate temperature solid oxide fuel cells (IT-SOFCs) anodes. Y0.08Sr0.88TiO3-delta and Y0.08Sr0.92Ti1-xFexO3-delta (x = 0.2, 0.4) anodes were prepared by infiltration in 65% porous yttria stabilized zirconia (YSZ) scaffolds. The microstructure and electrical conductivity of Y0.08Sr0.88TiO3-delta and Y0.08Sr0.92Ti1-xFexO3-delta strongly depends on Fe content. The conductivity of Y0.08Sr0.88TiO3-delta andY(0.08)Sr(0.92)Ti(1-x)Fe(x)O(3-delta); decreases with increasing Fe content in humidified H-2. Y0.08Sr0.88TiO3-delta, Y0.08Sr0.92Ti0.8Fe0.2O3-delta, and Y0.08Sr0.92Ti0.6Fe0.4O3-delta, anodes with a Pd/CeO2 catalyst show peak power density of 298, 421, and 321 mW cm(-2), respectively, in wet H-2 at 1073 K.open0

    Achieving both high selectivity and current density for CO2 reduction to formate on nanoporous tin foam electrocatalysts

    Get PDF
    Currently, low catalytic activity, selectivity and stability are the biggest challenges which restrict the large scale applications of CO2 electrochemical reduction. Formic acid, one of the highest value-added products from electrochemical reduction of CO2, has gathered much interest. Here, we develop nanoporous tin foam catalysts which exhibit significantly high selectivity and faster production rate to formate. In a 0.1 M NaHCO3 solution, the maximum Faradaic efficiency for formate production reaches above 90% with a current density over 23 mA cm-2 , which are among the highest reported value to date under ambient conditions. The improved production rate can be attributed to the high surface area and porous structure. Moreover, the electrocatalysts are quite stable, namely, the Faradaic efficiency remains unchanged during 16 hour electrolysis. This is a promising technology to convert CO2 into useful hydrocarbons

    Material properties, cytotoxicity and clinical efficacy of tricalcium silicate based cements

    Get PDF

    Offline Database Access

    Full text link
    Most of the People around the globe are not familiar with internet, the reason for inaccessible internet may vary region to region, somewhere because of geographical hurdles but internet has become one of the vital elements of survival for them. In such a scenario, there are parts of the Globe that doesnrsquot receive internet facility, or governmental restrictions.In some places, such as rural areas and remote regions, cell towers and Internet cables simply donrsquot exit. The connectivity will be achieved with the help of remote database access through wireless medium. Once the data has been sent to outernet server we can access it at anytime and anywhere by offline database (Without internet)
    corecore