Depends on what you value.
I value life style and flexibility-I do want a higher paid career (and yes dentists earn more than doctors) and I wanted to know my hours wouldn't eat into weekends. This is because my partner works mon-fri so I wanted to ensure we have time together, if this were sacrificed, our relationship would suffer.
I want to be the boss, I want to run a business and know it's mine and be able to focus it into any direction I choose . Doctors (unless gp and opening a practice) tend to work for the nhs and thus have a "boss" and more traditional employment ie a contract etc much easier for a dentist to go solely private than a doctor
Dentistry offers enough science and research to appease my scientific thirst for knowledge with out me feeling I need to know EVERYTHING about the human body. I'd rather be an expert on people's heads and have an good knowledge of the body. Basically I like focus
I like continuity of care, seeing the same patients over and over and building a rapport.
I like the artistry and intricacy involved in dentistry, along with the aesthetic difference you make to people. Something you generally don't get with being a doctor.
And I like the simple fact that people rarely die at the dentist. A element of doctoring you can't get away from and I feel I can't deal with.
I'd recommend doing some work experience and consider every aspect of your future life before you decide.