The fields, except that they are professional schools related to health in some way, have little in common.
Dentistry is a procedure/surgical based field. Optometry is not. Dentistry is also a field where residency training(at least in the form of a general practice residency) is pretty much the minimum standard for new grads. That is not the case in optometry. And while the individual percentages of endodontists, orthodontists, periodontists, pediatric dentists, OMF's, etc is pretty small, adding up *ALL* these dental subspecialties together with people graduating now shows that a large number of new grads are pursuing these areas, often after a GPR year or two.
I would also bet that dental school is far more taxing in terms of work hours and intensity than optometry school. Having gone to a medical school that also had a dental school, I knew plenty of dental students and saw hour busy they were years 1 through 4. They work *hard*....harder than medical students in most cases, and often by a good bit. The number of cases/procedures they have to master in dental school(while completing all the 'book' study work) is massive. It is not uncommon for dental schools to average 65 or so hours of work per week(actual work, not sitting around waiting for patients to come) throghout dental school. By contrast, if this forum is any indication OD school is much less rigoruous in terms of the intensity of training. And I don't say that as a criticism- I suspect a lot of OD students wouldnt want to work like dental students.
Another obvious difference is that dentists are the apex providers in their field, whereas in eye care optometrists obviously aren't.
Most importantly, competition to enter these two fields is in no way similar. Optometry school, and more importantly the difficulty in getting into some optometry school, is not all that difficult. Optom school applicants to total spots is now less than 1.4/1, and that's before considering how there is a lot of self selection *in* to optometry school from more competitive schools in the first place. I wouldn't pretend to know what exact percentage of optom school matriculants could have gotten into dental school somewhere, but it's almost certainly pretty low. Furthermore, it's more than just about stats....where I went to med school the dental students tended to either have undergrads from either the well respected large state university(ie not regional smaller universities that are less competitive) or impressive private undergrads that are top 25 nationally(Duke, Vanderbilt, etc)....there were very few people from smaller less regarded regional state schools with lesser standards. Something to keep in mind when comparing one 3.6 to another 3.6.
So I'm just puzzled to see so much advice along the lines of 'you should consider dental school instead of optometry school'. Ummm...ok...by that same reasoning I should have considered going to PGA tour qualifying school. PGA tour golfers make a lot more than I am making now, have more autonomy, better hours, etc....