Most teeth whitening kits on sale in super markets and online come with teeth whitening trays.
These trays perform an important task.
When you put the teeth whitening gel on your teeth and leave it without anything to protect it, it will get washed away by your own saliva not giving the bleaching agent in gel a chance to work on your teeth.
The trays, which can be molded to fit your teeth exactly, on the other hand will protect the gel from the fluids in the mouth and prevent it from getting dissolved.
This will let the whitening agent to work on the teeth for the required amount of time say 30 minutes or one hour or even overnight while you sleep.
Do read the instructions on the kit carefully before you leave it on all night.
The bleaching gel contains Carbamide peroxide or hydrogen peroxide which in higher strengths or prescription strength should not be left for a long time on the teeth.
This can damage the enamel and cause it to break down making it susceptible to bacteria and plaque.
Sometimes, after in-office dental cleaning your dentist will give you a few trays to take home to continue your treatment for touch ups.
These trays are molded according to the requirement of your teeth.
The dentist will also give the requirement amount of bleaching liquid or gel to be used at home.
Make sure to ask the dentist or the dental assistant about the time frame you can safely leave the tray on.
Don't exceed this time limit.
Teeth whitening trays are more effective than using strips or toothpaste to whiten your teeth.
These trays take one or two applications a week to start showing dramatic difference in your smile.
They are a bit more expensive than the other two options but they are much cheaper than dental office cleaning or laser teeth whitening.