Dentistry is different from other professions OP.
I am very worried about how you're looking at dentistry and medicine. I suggest you do two things A. If you do want to pursue dentistry you will need to shadow extensively as it is to build your application. Your medical school issue will not easily be overlooked by adcom. You must volunteer as well. Many schools have requirements for hours. This will enable you to perhaps realize that "better than now" may not be worth it if you're simply interested in providing for your family. This is an honest desire that everyone has. It's very commendable you want to do better, but you must think clearly and thoroughly. As a practicing dentist, your hand skills will dictate your life. Are you good with working with your hands? Have you had experience in this area? Adcom looks for this. While nothing you do out of dental school can prepare you for dental hands-it will help- With the PAT especially. Also, would you want to work in other people's mouths? Some would rather not. Others, don't mind it.
OP, with 10 years of undergrad behind you. I would consider another profession all together and I would shadow all options. You are a science person? Consider engineering, physician's assistant, physical therapy, or pharmacy. Engineering is very respectable, you earn a great income, you have job stability, you do not need to take a test, you can work straight out of undergrad, it will not take nearly as long, and it won't be nearly as expensive. Similarly, PA and PT are 2 year programs. No test required.
Pharmacy school is a lot cheaper, it's very science orientated-more so than dentistry I would say. It's very stable income. 90-100k out of pharmacy school is not uncommon. It isn't as competitive as dental or medical school, so you will be able to still spend time with you family while in undergrad(in terms of building EC). It is a very respectable career with good benefits. They may be more lenient towards your medical school problem. Pharmacy school isn't as strict on taking courses at a uni. Many people go to community college for two or three years and enter pharmacy school.
The reason why I suggest this to you is because dental school is a huge commitment. Besides the few years of intensive undergrad and the four years of intensive dental school, money is an issue. You will be around 150-400k in debt straight out of dental school. You will not simply start making 500k+ you will work as an associate for a few years until you build skill and reputation. After this, you may open up a practice(a 600k investment). Keep in mind that overhead will also curb your income for a short while. People think dentist make a steady salaried income, this is not the case. Depending on your business skills, location, staff, schedule, clinical ability, time, and personality you may very well end up making 90k a year with all that debt. It does happen. As with all professions, dentistry too is becoming competetive with older dentists delaying retirement and the market saturating. Consult the BLS for more general information.
Consider the above, and everything all the other posters have said. I have seen many people trying to jump ship to dentistry or medicine or pharmacy to "provide for their family." It isn't that simple or straightforward.
