People surfing the web for a dentist are usually looking for something special. Something a little bit different. Every week I receive a couple of requests for appointments from potential new patients who literally fill out an on-line request form. Also consider having small books or articles about various dental topics available for surfers to download. The more information available, the more they'll want to return to your site.
Folks surf the net, entering key words into search engines.
My practice is near Boston, Massachusetts. Perhaps you are in Tulsa, Oklahoma. A surfer in Tulsa looking for a dentist who does lots of porcelain veneers ends up on my web site. When he reaches the office information page he sees that I am quite a distance from Tulsa. This happens more often than not, with the web.