I want to more whiten my teeth. is there any toothpaste in market or can i have any treatment without side effect?

Not really: Whitening tooth pastes tend to be very weak whitening agents at best (they typically do not have side effects). You could try whitening strips which tend to work reasonably well. In-office bleaching with dentist tends to be the most effective.

Whitening : Yes there are many whitening toothpaste available in the market and they all generally work well. One of the most common side effects are teeth sensitivity. If you are looking for a serious whitening you need to see your dentist for an in office whitening

Varies: To whiten your teeth more requires one to have the whitening product for longer period of time in contact with your teeth. Side effect is usually sensitivity with the product, which over time will diminish.

Professionally Bleac: The toothpastes marketed for bleaching teeth aren't very effective because the concentration of peroxide isn't very high and you don't brush for very long. If you want the best results have your teeth professionally whitened at your dentists office. Another option is to use white strips.