I would say more than half of the dentists I know in the Army have kids. One of them just got slated to do a 2-year brigade slot, and will definitely deploy. The chance of getting injured during a deployment is low, and you likely won't be doing much on deployment based on presentations I've seen from brigade dentists, but you will definitely be away from your family for 5-9 months at a time.
That being said, there are many more people that don't deploy, and may never deploy (currently). The reverse-PROFIS system that's starting up seems like (?) it will make it much more likely that we all deploy. Not an issue since we did sign up for the Army, just know that you'll be away from your family for a bit if that happens.
It's not easy with a family, but many people do it. Your husband may have a hard time getting a job with moving around, and it would likely be better when your kids are young to move rather than when they're getting older and need more stable friendships outside of the family.