Search results for "Calcium"
showing 10 items of 1740 documents
Response of periodontium to mineral trioxide aggregate and Biodentine: a pilot histological study on humans.
2018
Background The aim of this study was to investigate for the first time the histological response of human periodontium to mineral trioxide aggregate (MTA) and Biodentine. Methods Six patients scheduled for implant full-arch rehabilitation were randomly assigned to one of the two test groups: MTA or Biodentine treatment. For each patient, two teeth scheduled for strategic extraction were randomly assigned either to the test or to the control treatment. A lateral perforation was drilled on the root and either repaired with MTA/Biodentine or filled with gutta-percha(control). Three months later, the teeth were extracted along with the coronal third of the alveolar bone and a portion of gingiva…
Effect of pH on compressive strength of some modification of mineral trioxide aggregate
2013
Objectives: Recently, it was shown that NanoMTA improved the setting time and promoted a better hydration process which prevents washout and the dislodgment of this novel biomaterial in comparison with WTMA. This study analyzed the compressive strength of ProRoot WMTA (Dentsply), a NanoWMTA (Kamal Asgar Research Center), and Bioaggregate (Innovative Bioceramix) after its exposure to a range of environmental pH conditions during hydration. Study Design: After mixing the cements under aseptic condition and based on the manufacturers' recommendations, the cements were condensed with moderate force using plugger into 9 × 6 mm split molds. Each type of cement was then randomly divided into three…
Assessment of the interaction of Portland cement-based materials with blood and tissue fluids using an animal model
2016
Portland cement used in the construction industry improves its properties when wet. Since most dental materials are used in a moist environment, Portland cement has been developed for use in dentistry. The first generation material is mineral trioxide aggregate (MTA), used in surgical procedures, thus in contact with blood. The aim of this study was to compare the setting of MTA in vitro and in vivo in contact with blood by subcutaneous implantation in rats. The tissue reaction to the material was also investigated. ProRoot MTA (Dentsply) was implanted in the subcutaneous tissues of Sprague-Dawley rats in opposite flanks and left in situ for 3 months. Furthermore the material was also store…
Effect of alkaline ph on sealing ability of white mineral trioxide aggregate
2011
Objectives: The aim of this study was to evaluate microleakage of white mineral trioxide aggregate (WMTA) after its exposure to a range of alkaline environments during hydration. Study Design: Seventy single-rooted teeth were divided into 4 experimental and 2 control groups. All the teeth were instrumented, and their apices were resected. Root-end cavities were filled with WMTA in the experimental groups. In the control groups, root-end cavities were not filled. Root-end fillings were exposed to alkaline environments with pH values of 7.4, 8.4, 9.4, or 10.4 for 3 days. Microleakage was evaluated by bovine serum albumin. Evaluations were carried out at 24-hour intervals for 80 days. Data wer…
Mineral trioxide aggregate in primary teeth pulpotomy. A systematic literature review
2009
Evidence-based dentistry is a critical evaluation, awareness of the available evidence to improve decision making about the care of individual patients and / or communities. Objective: To systematically analyze the available scientific literature on clinical and radiographic results of two materials used in pulpotomy in primary teeth: formocresol and mineral trioxide aggregate. Materials and methods: It was identified relevant publications through a search of electronic databases such as MEDLINE (Ovid) and The Cochrane Library. To be included in the review, studies had to define the material used in child patients with pulp exposure by caries or tooth-alveolar trauma. Results: Of the 21 art…
Study of two MTA cements
2014
Introduction: To determine and compare the pH, conductivity and calcium release of an experimental Portland cement (PE) consisting of trioxid mineral aggregate and a comercially available modified Portland cement (C.P.M.) after 1, 2, 3, 4, 8, 10, 15 and 30 days. Material and Methods: Cements were mixed following the manufacturer's instructions, with a powder: liquid ratio of 3:1. Each cement was placed in 12 PVC tubes 1 mm in diameter and 10 mm in length and allowed to set. Four empty tubes were used as negative controls. Tubes were submerged in plastic flasks containing 10 ml deionized water and stored at 37ºC and 100% humidity. After 1, 2, 3, 4, 8, 10, 15 and 30 days tubes were removed fr…
Microleakage comparison of glass-ionomer and white mineral trioxide aggregate used as a coronal barrier in nonvital bleaching
2011
Objectives: There is some evidence that the pH at the root surface is reduced by intracoronal placement of bleaching pastes, which is known to enhance osteoclastic activity. Therefore, it is recommended that a protective barrier be used over the canal filling to prevent leakage of bleaching agents. Glass-ionomer (GI) is commonly used as a coronal barrier before nonvital bleaching. Because mineral trioxide aggregate (MTA) creates high alkalinity after mixing with water, using MTA as a protective barrier over the canal filling may not only prevent leakage of bleaching agents and microorganisms, but may prevent cervical resorption. The aim of this study was to evaluate sealing ability of white…
The Discoloration effect of White Mineral Trioxide Aggregate (WMTA), Calcium Enriched Mixture (CEM), and Portland Cement (PC) on Human Teeth
2017
Background The aim of this study was to evaluate the discoloration induced by CEM cement, Portland cement (PC) and MTA mixed with propylene glycol (MTA-PG) in comparison to White MTA. Material and methods Ninety extracted premolar and canine teeth were resected 2 mm below the CEJ. The coronal part of crown was prepared with peeso reamer and Gates-Glidden drills, and the specimens were randomly divided into 4 experimental (n=20) and one control (n=10) groups. The tooth crowns in experimental groups 1 to 4 were filled with White MTA, PC, CEM cement and MTA-PG, respectively; and in group 5, the teeth were kept empty. After incubation, digital photographs of teeth were acquired at 4 time points…
Stable amorphous calcium carbonate is the main component of the calcium storage structures of the crustacean Orchestia cavimana.
2002
Amorphous calcium carbonate (ACC) is the least stable form of the six known phases of calcium carbonate. It is, however, produced and stabilized by a variety of organisms. In this study we examined calcium storage structures from the terrestrial crustacean Orchestia cavimana, in order to better understand their formation mode and function. By using X-ray diffraction, infrared and Raman spectroscopy, thermal analysis and elemental analysis, we determined that the mineral comprising these storage structures is amorphous calcium carbonate with small amounts of amorphous calcium phosphate (5%). We suggest that the use of amorphous calcium carbonate might be advantageous for these storage struct…
Bioactive glass ions as strong enhancers of osteogenic differentiation in human adipose stem cells.
2015
Bioactive glasses are known for their ability to induce osteogenic differentiation of stem cells. To elucidate the mechanism of the osteoinductivity in more detail, we studied whether ionic extracts prepared from a commercial glass S53P4 and from three experimental glasses (2-06, 1-06 and 3-06) are alone sufficient to induce osteogenic differentiation of human adipose stem cells. Cells were cultured using basic medium or osteogenic medium as extract basis. Our results indicate that cells stay viable in all the glass extracts for the whole culturing period, 14 days. At 14 days the mineralization in osteogenic medium extracts was excessive compared to the control. Parallel to the increased mi…