Taking one or two CC classes to get you back in the swing of studying isn't a bad thing. However, the bulk of your come-back work should not be at CC. It will be perceived, and correctly, that you couldn't hang at a 4-year place so dropped down a level and are excelling there. That tells AdComs that you excel at CC level, which is a long way from dental school level.
How informal post bacs work has been discussed at length in the forum. Do some reading and it will be come apparent.
Re: the # of years of recovery. You have a long road ahead of you, at least two full time years at university level to even have a shot at a SMP, and then you are another 2 years away from matriculating (year of SMP and a glide year). So you are 4-years MINIMUM (if you get As in everything) from being competitive for dental school. More probable is 5 years, maybe even 6 if you don't pull As. If you want this road, then there are no short cuts.
There is no "i f*cked up college and found a secret 6 mo back door into med/dent school".