The aim of this in vitro study was to evaluate enamel microhardness following bleaching treatments using either high- or low-concentration hydrogen peroxide (HP) agents containing calcium and/or fluoride. Sixty enamel blocks were bleached with 1 of 6 different bleaching agents (n = 10). The high-concentration HP agents were Whiteness HP Maxx (35% HP), Whiteness HP Blue (35% HP, 2% calcium gluco...

High concentrations of arsenic have been detected in soils and underlying groundwater of some South Florida golf courses, indicating the possible impact of the application of arsenic-containing herbicides. The mobility of arsenic in the soils from selected golf courses was studied using a simple two-step sequential extraction procedure. Sodium nitrate (0.1 M), potassium dihydrogen phosphate (0....

Consumption of acidic foods and drinks and other factors that cause enamel wear are responsible for the daily enamel loss and degradation. Use of some toothpastes that have been showed to possess different properties of remineralisation and/or repair of the enamel surface may help to protect tooth enamel. The aim of this study was to evaluate whether the use of toothpaste containing Zn-carbonat...

BACKGROUND Dental whitening has been increasingly sought out to improve dental aesthetics, but may cause chemical and morphological changes in dental enamel surfaces. OBJECTIVE This study evaluated in vitro the effect of 10% strontium chloride and 5% potassium nitrate with fluoride on bovine enamel, through tristimulus colorimetry, Knoop microhardness (KHN), and roughness after bleaching with...

In 6 dogs, experiments were performed to determine the tissue reaction of the dental pulp at the 7, 30 and 60 days after direct contact of the pulp with the obturation material through a microcommunication orifice with diameter up to 1 mm, formed in the fundic part of an experimental cavity. Capping of 36 mandibular premolars with traumatically exposed pulp was carried out. On the exposed pulp,...

Precipitation titrations are based upon reactions that yield ionic compounds of limited solubility. The most important precipitating reagent is silver nitrate. Titrimetric methods based upon silver nitrate are sometimes termed argentometric methods. Potassium chromate can serve as an end point indicator for the argentometric determination of chloride, bromide and cyanide ions by reacting with s...

OBJECTIVE This clinical study aimed to evaluate effectiveness of a commercially available toothpaste containing potassium nitrate, sodium monoflurophosphate, and nano-hydroxyapatite as well as antioxidants phloretin, ferulic acid and silymarin in reducing dental hypersensitivity in adults. METHODS The clinical trial enrolled patients with a history of dentin hypersensitivity. A test toothpast...

Root cortical aerenchyma (RCA) is induced by hypoxia, drought, and several nutrient deficiencies. Previous research showed that RCA formation reduces the respiration and nutrient content of root tissue. We used SimRoot, a functional-structural model, to provide quantitative support for the hypothesis that RCA formation is a useful adaptation to suboptimal availability of phosphorus, nitrogen, a...

OBJECTIVE To determine the ability of various marketed dentifrices containing stabilized stannous fluoride (SnF2), sodium fluoride (NaF), or sodium monofluorophosphate (SMFP) to protect enamel against the earliest stages of erosive dietary acid damage using an in vitro enamel protection model. METHODS Acid-challenged, extracted human teeth were treated with a 1:3 dilution of dentifrice, rinse...

Studying seed dormancy and its consequent effect can provide important information for vegetation restoration and management. The present study investigated seed dormancy, seedling emergence and seed survival in the soil seed bank of Stipa bungeana, a grass species used in restoration of degraded land on the Loess Plateau in northwest China. Dormancy of fresh seeds was determined by incubation ...