i think you do have a shot if you apply very early. my stats are pretty much like yours but maybe a little better and i got into Tufts.
my dat is like 19TS/18AA/20pat. sci gpa is 3.19 and average gpa is 3.56. I did research in college and have about 200+ hrs shadowing experience. Since you are a dental hygienist for 3 yrs, you definitely have more experience than i do. i applied pretty late like at the end of Aug. and have had 2 interviews so far. I think if you apply early and apply to 10+ schools that take ppl w/ average/low stats, you may get one or two interviews and you'll get in if you get luck and get a very good interviewer.
However, just like what the others said, if you really want to get into dental school, you better do a master program to raise your gpa and/or retake your dat. As you can tell, the trend in dat scores is increasing each yr and you want to be a competitive candidate among all other applicants.
good luck.