teeth whitening for sensitive teeth?

I tried the crest white strips from the store and they made my teeth hurt really bad!! what else is available over the counter for sensitive teeth?
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Teeth whitening is a cosmetic treatment done to improve the appearance of teeth. But it is not safe or effective for everyone. Sensitive teeth can be considered as a reason for that, or, what is worse, as a result. Tooth sensitivity is tooth discomfort in one or more teeth that is triggered by hot, cold, sweet or sour foods and drinks, or even by breathing cold air. The pain can be sharp, sudden, and shoot deep into the nerve endings of your teeth. Different causes of sensitive tooth influence differently on the future whitening process. Brushing too hard, for example, produces tooth sensitivity and it would be better not to bleach your teeth in this period of time because the enamel is worn down and the dentine become exposed. The roots' exposed surface, as a result of recession of the gums, will not allow a good dentist to white your teeth. In case this periodontal disease is ignored unnecessary and painful effects will follow. If the tooth is cracked or it must be filled firstly the needed treatment is done. Only after that teeth bleaching is possible. This rule can be used in case of any tooth or gum diseases. The age can be considered as a cause, too. The tooth sensitivity is highest between the ages of 25 and 30. In this case you can not worry about bad consequences. However, the last decision is made by the dentist you chose. Considering he or she is a good specialist, a correct direction in your future actions will be given. In case you decided to bleach your sensitive teeth, there exist three main methods. The first one and the most trusted is the whitening treatment provided by specialist, also called by dentists chairside bleaching, in-office bleaching, or power bleaching. The dentist first protects the patient's gums and tissue by applying a protective gel or a rubber shield. Than he applies a whitening solution on the teeth. This solution contains hydrogen peroxide, which is a bleaching agent that could change the tooth color. This bleaching agent comes in concentrations ranging from 15% to 35%, and only 10% in the case of sensitive teeth. After the gel is applied, a light may be shined on the teeth to accelerate the whitening agent. The whole process can last from thirty minutes to an hour. Sometimes patients may need to return for additional treatments. The cost of treatment for the whole mouth can cost from $300 to $1,000. The second method is the dentist-supervised treatment and it combines visits to the dentist with treatment at home. For this sensitive teeth whitening process, the dentist takes an impression of the patient's teeth and makes a mouthpiece tray, or mouth-guard, that will fit over the teeth. The dentist dispenses a whitening gel that the patient will place in the customized mouth-guard. The gel usually contains carbamide peroxide, which concentration is equivalent of an approximately 3% concentration of hydrogen peroxide. The dentist will set up a schedule for wearing the mouth-guard. A patient may wear the piece overnight for one to two weeks. For other systems, or a set amount of time twice a day. This treatment usually lasts two weeks. Supervised home sensitive teeth bleaching costs from $200 to $600. The third method is the in-home treatment. It usually includes different kinds of gels, whitening strips, and whitening toothpaste, a lot of time, but less money. No matter what method you chose. The important thing is to have a dental exam before starting treatment. After that the dentist can advise you the most appropriate procedure. He or she will also discuss the expected results of treatment and will carefully pay attention to the possible defects. Following all specialist's recommendations you can have even your sensitive teeth bleached.
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