Whitening itself is not permanent and how long it lasts depends on your care and maintenance.

For quick results, you would need to visit a dentist and do in-office whitening where the Dentist does the bleaching for you, immediate results can be seen.

You could add-on for a home whitening kit for your to maintain your whitening at home on your own.

Usually the in home whitening give stable results but it will be slower and can be self maintained.