If your discoloration problem is primarily from extrinsic staining, you can often get very good results using toothpastes that advertise themselves as “whitening toothpastes“. This method is only for extrinsic staining and is not part of this discussion on actual bleaching procedures.
The first type of delivery system for tooth bleaching is the in-office procedure performed by a dental professional. These procedures use the highest concentration of bleaching agent and it is generally going to be a hydrogen peroxide agent, which tends to be stronger than carbamide peroxide. Carbamide peroxide breaks down into hydrogen peroxide when activated. When high concentrations of hydrogen peroxide (9-40%) are used, the gum tissues must be protected by isolation with a dental rubber dam and the agent applied carefully and monitored.
These procedures are much faster than other methods, but also correspondingly more costly. The cost can range from $500 – $700. Many of these systems are used with an activating light of some kind. There is controversy in the profession about the effectiveness of this light activation and some studies seem to show no significant difference between light activation and no light.
Professionally Dispensed At-Home Bleaching Kits
The second type of delivery systems for bleaching the teeth is custom tray fitting with professionally dispensed bleaching products. An impression is taken of the teeth in the dental office, a custom tray is produced from this impression and the patient takes the tray and bleaching material home to wear the bleach filled trays from 1/2 hour to 1 hour per day, depending on the product used.
These products rely on the less strong, but safer agents using carbamide peroxide. As mentioned, the carbamide peroxide breaks down into hydrogen peroxide having about 1/3 the strength of hydrogen peroxide. A 15% carbamide peroxide solution is equivalent to about a 5% hydrogen peroxide solution. It usually will take a couple of weeks of consistent use to get the desired whiteness of the teeth with these systems. The cost is usually only about $150 – $300.
Over-The-Counter Bleaching Kits
The third category of bleaching systems is the over-the-counter store bought whitening kits. These systems have the lowest concentrations of bleaching agent which is usually applied with a general sized tray, some kind of strip, or painted onto the teeth with applicators. This results in considerably less accurate dispensing of material to the teeth. This can result in burning and discomfort to the gums, and uneven whitening results overall. There is also a tendency for these systems to only be able to whiten some of the front teeth as opposed to the full arch whitening possible with custom fit trays. These systems typically cost from $20 – $100.
It should be noted that whichever type of bleaching system one chooses, no amount of bleaching can achieve a whiter shade than a person’s own natural optimum whiteness. If bleaching is carried out beyond professional instructions, the enamel can lose its luster and be left with a chalky appearance which weakens the surface. If proper directions are followed this danger is very minimal, so follow the directions.
Various shade guides are dispensed with these kits for analyzing your beginning tooth color and your progress towards a lighter shade. There are many factors affecting the outcome of bleaching procedures and it is important to have a realistic expectation when trying to achieve a lighter (whiter) tooth color. Usually, from two to five or six steps on a shade guide is realistic. Your dentist can give you a good idea what you can expect given the condition of your teeth.
What I often do with my patients is to show them a shade guide representation of their current tooth color next to the shade they might realistically hope to achieve. Then I will suggest that instead of using the paper shade guide that comes with most kits, I ask them to bleach first the upper teeth and use their own lower teeth to measure their progress. Then when they have reached their desired goal, they can bleach the lowers to match the uppers.