Yes, it is possible. I joined the Air Force on an HPSP scholarship my first year of dental school. Around my second year I realized I wanted to do a 6 year OMS residency. Unfortunately the AF didn't offer one, so I set about applying for deferment. Like everyone else has said, its not common. It basically took me putting in a few calls to the graduate dental education office and explaining my situation. They also wanted me to apply to their residency programs but I was insistent on doing a 6 year program so I could have a medical degree (would I make the same decision now...I don't know, four year programs look pretty good when you're studying for all your med school stuff...but thats another topic). Eventually my requests got me through to the oral surgeons in charge of their residencies, I had to do a phone interview. I think they were basically making sure I would match to a 6 year program in the civilian world. They also made me apply to their AEGD program as a backup in case I didn't match. However I did match and the rest is history. So I owe them the years they paid for my dental school, I'm not sponsored at all currently through residency (but the hospital pays my salary, so its all good).
