Okay, I know you wanted someone in the city. However, when I was living in SF, I used to drive about 40 minutes out towards Los Gatos to go to my dentist. The whole staff is very friendly, conscientious, and professional. I HATE going to the dentist, and Dr. Vu started out with this other dentist my mom used to work for in the city. He spread out and I followed up.
The prices are a bit steep. But they're very careful with cleanings. Also, the place is pretty high tech--if you wanted, you can ask them to show you what they are doing on screen. I however, prefer to use the screen to watch DVDs. That's right, movies while you get your teeth cleaned.