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A nitrite test is a standard component of a urinary test strip. A positive test for nitrites in the urine is called nitrituria. This test is commonly used in diagnosing urinary tract infections (UTIs). A positive nitrite test indicates that the cause of the UTI is a Gram-negative organism, most commonly Escherichia coli. The reason for nitrites ...
To prevent future buildup of extrinsic stains, identification of the cause (e.g., smoking) is required. Intrinsic discoloration generally requires one of the many types of tooth bleaching . Alternatively the appearance of the tooth can be hidden with dental restorations (e.g., composite fillings, veneers , crowns).
Azo violet can be synthesised by reacting 4-nitroaniline with nitrous acid (generated in situ with an acid and a nitrite salt) to produce a diazonium intermediate. This is then reacted with resorcinol, dissolved in a sodium hydroxide solution, via an azo coupling reaction. This is consistent with the generalized strategy for preparing azo dyes.
Phenazopyridine is an azo dye. [17] [18] Other azo dyes, which were previously used in textiles, printing, and plastic manufacturing, have been implicated as carcinogens that can cause bladder cancer. [19] While phenazopyridine has never been shown to cause cancer in humans, evidence from animal models suggests that it is potentially ...
Supragingival biofilm is dental plaque that forms above the gums, and is the first kind of plaque to form after the brushing of the teeth. It commonly forms in between the teeth, in the pits and grooves of the teeth and along the gums. It is made up of mostly aerobic bacteria, meaning these bacteria need oxygen to survive.
Azo compounds are organic compounds bearing the functional group diazenyl (R−N=N−R′, in which R and R′ can be either aryl or alkyl groups).. IUPAC defines azo compounds as: "Derivatives of diazene (diimide), HN=NH, wherein both hydrogens are substituted by hydrocarbyl groups, e.g. PhN=NPh azobenzene or diphenyldiazene.", where Ph stands for phenyl group. [1]
Cetylpyridinium chloride is known to cause tooth staining in approximately 3 percent of users. [14] The Crest brand has noted that this staining is actually an indication that the product is working as intended, as the stains are a result of bacteria dying on the teeth. [ 15 ]
The nicotine and tar in tobacco, combined with oxygen, turns yellow and over time will absorb into the pores of enamel and stain the teeth yellow. The dark brown to black stains along the gum line of the teeth are the result of the porous nature of calculus immediately picking up the stains from nicotine and tar. Betel chewing. [12] Betel ...