Is it permissible to go to the dentist to clean and whiten yellow teeth?

There is no harm in going to the dentist for teeth cleaning and whitening. This is not considered changing the creation of Allah, but rather it is to remove the yellowness from them so they return to their natural cleanliness. The Messenger of Allah, peace and blessings be upon him, encouraged the use of the siwak to purify and clean the mouth. Scholars have mentioned that the yellowing of teeth is one of the reasons for the desirability of using the siwak.