Why Teeth Stain
There are many causes of tooth discoloration. The most common causes include consumption of staining substances (smoking, coffee, tea, soy sauce, berries and colas), tetracycline (antibiotic) staining, excessive fluoride, old fillings, aging and genetics. Store-bought whitening toothpastes can remove external stains that are on teeth, but stains that are deep within teeth won’t bleach out. Whitening toothpastes and professional dental cleanings will not change the internal color of teeth, nor will they be able to remove intrinsic stains located deep within the teeth.
How Does Whitening Work?
There are basically two ways to whiten teeth professionally–customized whitening trays, or in-office whitening.
Whitening gel is placed in a customized tray that fits over your teeth and as the active ingredient in the gel, carbamide peroxide, is broken down, oxygen enters the enamel and bleaches out colored substances. The structure of the teeth are not changed; the teeth are just made lighter and brighter. Fillings, Crowns, and Bonding will not lighten.
Just recently, a new type of whitening procedure has been developed that does not require customized trays. Pre-fit trays, similar to Crest whitestrips but with professional strength whitening agents, are now available (by prescription only) that are just as effective as customized trays.
Is Whitening Safe?
Tray whitening or bleaching is a fast, safe and predictable way to whiten teeth 2-5 shades in a matter of days. The peroxides used in professional whitening agents do not alter tooth structure. Some people will experience sensitivity to these agents, which is a common (and temporary) side effect and there are agents that can be applied to eliminate sensitivity completely. Individuals whom are using Crest Whitestrips or other over-the-counter whitening agents should proceed with caution because excessively whitening your teeth can make your teeth indefinitely sensitive and the whitening agents in these systems can cause chemical burns on gum tissue.
What is the Difference Between In-office One-hour Whitening and Custom Whitening Trays?
In-office whitening utilizes a 35% Hydrogen Peroxide solution on your teeth. Once this whitening gel is in place, a chemical reaction takes place that will drive oxygen into the tooth enamel, bubbling out minute stains. Not only will in-office whitening yield better results, but it is safer and longer-lasting. Your gums are carefully protected with a plastic resin barrier so that the whitening gel cannot leech onto the tissues, thereby preventing chemical burns. Additionally, since in-office whitening incorporates three, 15-minute applications within the one hour visit, it is possible to whiten teeth to match existing crowns or veneers.
How Does Professional Whitening (Customized Trays or In-Office Whitening) Compare to Crest White Strips?
Crest White Strips are plastic strips that are coated with Hydrogen Peroxide and placed onto the front teeth. The strips do work, somewhat. Clinical tests by Crest show that teeth are lightened an average of 1 to 2 shades, compared to an increase in brightness of 4-6 shades with professional whitening systems. Also, they will only whiten front teeth leaving visible premolars dark and dingy.
How Long will Whitening Results Last?
For most people, the treatment is long-lasting. Exposure to coffee, tea, smoking, red wine, berries, dark sauces and some medicine products will gradually darken teeth again over time. After an initial treatment, most people do touch-ups one day about every 3-6 months (for customized trays), or once a year for in-office whitening.
How Long Does it Take to Whiten with Customized Trays and How White Will They Get?
When wearing customized trays, Carbamide Peroxide is slowly broken down to Hydrogen Peroxide which whitens the teeth. The 16% gel whitens more slowly but causes less tooth sensitivity. A 22% gel is available that will whiten more quickly but can cause temporary sensitivity to temperatures. Both the 16% and 22% gels need to be worn for about 30 minutes a day for 10-14 days to achieve maximum whiteness. Virtually everyone who whitens their teeth will see improvement.
The ultimate whiteness will be determined by the length of time the teeth are exposed to the whitening gel and the mineral composition of the teeth. Teeth whitening is kind of like a reverse suntan. Some people get great results in only one or two days while others need more treatment time.