you have one of the best theme with the logo of your website you need to woke according to the rules of Search Engine for making it a quality website.
the medic shoudln't have a teeth or something in his hand or somewhere ? i think it will make it a little better . Even like this looks pretty goood .
your logo is not looking good because it very small you need to do something special for your logo of site.
I agree with @Install. Sorry, I don't like it either. The guy in the logo looks more like a doctor than a dentist. Most of the dentist I've gone to do not wear a white lab coat. And why does he have blue hair?