Dental school is easier to get into than most medical schools. I knew several people who didn't even complete Organic Chemistry before taking the DAT (and Physics is not required at all for the DAT, although it is for admission, just like Organic Chemistry) and essentially bombed the Organic Chemistry section. They still applied (actually even a year earlier, NOT as Juniors) and even got into their number 1 choice of school. They had lots of interviews and just explained that their OChem performance was sort of weak due to the fact they hadn't taken Ochem and the schools were ok with that.
Also, looking at some of my dental buddies, they have it easier when it comes to grading. If you plan on general dentistry, you can pretty much just pass all your classes. Nobody cares since there is no residency. For all medical students, your grades and board scores are your ticket, so you may have to study harder/more to be competitive, in theory, than in dental school. Dental students have tons of lab work to do during the first 2 years which takes up tons of time besides trying to study for classes, so in that regard it may not be a ton less time spend during your education. However, one of my buddies also uses the abbreviated Robbins Path text book (as provided by the school), for example, rather than the thick juice version, which makes me think there are some differences.
It's the same as for medical school if you want to specialize after dental school, in which case you have to be very very very competitive.
I've had several docs I shadowed actually try to change my mind to go into dentistry insted of medicine. No way!
Also, many people prefer dental training since there is no residency, so you'll be practicing much earlier. Also, there are less hassles with payments and reimbursements than in medicine. Medical reimbursements will likely go down. Many dentists already bill the patient "whatever they want" directly and expect the patient ot pay (not dealing with insurance reimbursements and negotiations of contracts) and have the patient get back from their own insurance companies what they can get by submitting the bill themselves, even if they don't cover the whole procedure.