8/21/2001  
            People who want to brighten their smiles are opting for 
            over-the-counter bleaching kits instead of visiting their dentist's 
            office. While generally safe, these products have the potential to 
            cause an infection or nerve damage, say UT Southwestern Medical 
            Center at Dallas oral surgeons.
            
Dr. David McFadden, associate professor of oral and maxillofacial 
            surgery, suggests consulting a dentist so pre-existing conditions 
            can be diagnosed and treated before starting any type of bleaching 
            regimen.
            
"If a person has deep cavities, the bleach could have an 
            unimpeded route to the blood vessels, nerves and bone that are found 
            at the root of the tooth," McFadden said. "It can potentially cause 
            a bad toothache or precipitate an infection."
            
People with active periodontal disease may also notice 
            soft-tissue shrinkage.
            
"This is not gum recession, but many patients perceive this as a 
            negative side effect. In actuality, bleaching provides short-term 
            improvement," McFadden said. "The effervescent action of the bleach 
            helps keep the teeth cleaner."
            
The color of one's teeth is determined by genetics. Dentin, a 
            hard, yellow substance that surrounds the pulp, shows through the 
            enamel so most teeth appear slightly yellowish. Other factors that 
            affect tooth color are aging, tetracycline medications, 
            over-fluoridated water and chromogenic agents found in coffee, tea 
            and carbonated drinks.
            
"Many over-the-counter bleaching agents are weak and will not 
            create a drastic change in tooth color," McFadden said. "And since 
            the bleaching trays are not custom-fitted to your teeth, the uneven 
            distribution of bleach may cause spotting." Overusing bleach to 
            attain perfectly white teeth could also cause tooth damage, McFadden 
            said.
            
"Using too much bleach can cause extreme tooth sensitivity. The 
            pain related to overuse usually causes people to stop bleaching 
            before it does any significant harm," McFadden said. "But it's 
            possible that they could damage the nerve enough to require 
            root-canal therapy."
            
There are other, albeit more costly, options for people with 
            severely discolored teeth. Porcelain veneers - thin, 
            semi-translucent porcelain shells that are permanently bonded to 
            teeth - can provide an aesthetic improvement. For laser bleaching, a 
            dentist applies a bleaching agent to the teeth, then uses an argon 
            laser to activate it.
            
A less expensive route to whiter teeth are custom-made bleaching 
            trays from your dentist, an option that costs about $300. Although 
            results vary from person to person, this process generally lightens 
            teeth two to three shades and lasts up to three years.
            
But the simplest solution to maintaining your pearly whites is 
            also the most overlooked: brushing your teeth after every meal.
            
"Food and beverages can stain the plaque and make teeth appear 
            yellow," McFadden said. "If people would just brush their teeth more 
            often, it would reduce the amount of plaque that accumulates."