I'd ask that dentist or other dentists if you could work for them. You'd probably end up doing a lot of scut work (filing charts, changing over rooms, etc...) but should have a good opportunity to learn a great deal as well as get some practical lab and office experience (pouring up models, processing x-rays, waxing). I'm working as an intern for a dentist right now, and its been a great experience and what I know a heck of a lot more about dentistry now than I did a year ago. Also, maybe look into working/volunteering at a dental lab. Should be a chance to gain some valuable lab skills.