name changes

Hello, I and my sister were adopted when we were in middle school and our last name have been changed since then. As we are now over 21 years old, we are trying to take back to birth last name. If I change my last name back to original name, then does it make any changes of relationship between me and my adopted parents? Like I am in college and all the health insurances are getting under my adopted parents as well. If I get new birth certificate, then still my adopted parents names will be on right? thank you!