My cap in the front of my mouth has a post that goes into my gum. It is extremely loose. How can I get it out?

It fell out months ago and I had it recemted. And it became loose last week when I was on vacation. And now I m home and my dentist is on vacation and it is extremely loose and uncomfortable. My bite is messed up, I have trouble eating, food is getting stuck in it by my gums. And it will not come out. it feels like cement is on the post that is up in my gum. What can I do to get it out until my dentist comes back next week. I cant deal with this for another week.