Thank you for your inquiry. This is a common question that is asked by a lot patients.
Dr. Huang has answered well, and I would like to add my thoughts.
As a direct-president of the aesthetic dentistry of the Society of Singapore, I have been exposed to a long list of ways to aesthetically whiten teeth.
In my opinion, once the teeth are sensitive, a tooth whitening procedure will be best suited for you, because everyone's teeth are unique.
In practice, the most common causes of teeth sensitivity are:
1. Abrasion Cavities
2. Extremely worn down teeth exposing the softer inner layer of teeth called Dentine
3. Dental Decay
4. Hairline cracks in teeth
Consultation and examination with your regular dentist.
I hope you find this information useful and I wish you all the best in your journey to get a nicer, whiter smile!