I had a root canal on my left front tooth 9 years ago with no crown. Last week my tooth broke and my dentist put in temp crown which lasted a week when the rest of tooth broke off at the gum line. I then first realized that I push my tongue into that one tooth when I swallow and sleep. The dentist then did a post and core and I've noticed that I've already pushed the crown forward by about a mm and I'm terrified that this will cause a fractured root. What can be done and is my fear justified?