Go for "BrightSmile" teeth whitening system. The procedure
itself only takes 1 hour, and it is permanent (or at least very
long lasting). But there will have to be at least 1 cleaning
session appointment before the actual whitening appointment.
Here's a dental clinic in Mount Elizabeth Medical Centre that
offers the service :
http://www.yipdental.com/
There's at least one dental clinic on top of Parkway Parade (5th
floor, highest floor possible) that also offers this service. Just
walk around that floor, you'll see their "BrightSmile" teeth
whitening posters on their door, so easy to identify.
