Generally, bleaching is successful in at least 90% of patients, though it may not be an option for everyone.
Consider tooth bleaching if your teeth are darkened from age, coffee, tea, red wine or smoking. Teeth darkened with shades of yellow, brown or orange respond better to lightening. Gray stains caused by fluorosis, smoking or tetracycline can be lightened, but the results are not as dramatic. If you have sensitive teeth, gum disease, or teeth with worn enamel, your dentist may discourage bleaching.
How long does it last?
Bleaching should last 1 to 5 years, depending on your personal habits such as smoking and drinking coffee and tea.
At some point you may want a touch-up.
How does it work?
The active ingredient in most of the whitening agents is 10% carbamide peroxide.
When water comes in contact with it, the release of hydrogen peroxide lightens the teeth.
Is it safe? Are there any side effects?
Studies have proven bleaching to be safe and effective.
Some patients may experience slight gum irritation or tooth sensitivity, which ends when the treatment does.
What are the realistic expectations?
Typically, there is a two-shade improvement as seen on a dentist's shade guide. The success rate depends on the type of stain involved and your compliance. Bleaching can only provide a shift in color from gray to a lighter shade of gray. Bleaching does not lighten artificial materials such as resins, silicates or porcelains.
Reprinted with permission from the Academy of General Dentistry
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Food Irradiation
and Safety
On August 22, 2008, the Food and Drug Administration (FDA) published a final rule that allows the use of irradiation to make fresh iceberg lettuce and fresh spinach safer and last longer without spoiling.
Irradiating fresh iceberg lettuce and spinach will help protect consumers from disease-causing bacteria such as Salmonella and Escherichia coli O157:H7 (E. coli). Illnesses from these bacteria range from uncomfortable symptoms to life-threatening health problems.
The foods affected by the final rule are
Irradiation (also sometimes termed "ionizing radiation") is a process of treating products with a measured dose of radiation. Food irradiation is not new. FDA has conducted irradiation safety evaluations for more than 40 years and has determined the process to be safe for use on a variety of foods.
After studying the safety of irradiating fresh iceberg lettuce and fresh spinach, FDA has determined that these greens, when irradiated under the conditions specified in the final rule, retain their nutrient value and are safe to eat.
FDA considers irradiation a complement to, not a replacement for, proper food-handling by producers, processors, and consumers. Irradiation is just another tool to reduce the levels of disease-causing microorganisms on fresh iceberg lettuce and fresh pinach.
Irradiation does not take the place of washing. FDA continues to recommend that consumers wash fresh and bagged produce before eating unless the packaging specifically states that the product has been pre-washed.
For more information, go to: http://www.fda.gov)
