Basically to further clarify a dentation is where the officer has decided that they want to put some under temporary custody. Basically for questioning and the person is not free to go until the officer says they are free. This can lead to an arrest if probable cause, reasonable suspicion, and beyond a reasonable doubt can be met.
A arrest is basically putting someone into permanent holding until a trial can be held.
Miranda Rights: contrary to cop shows, you don't have to read your rights when being arrested. The only time you need your rights read is when you are in custody and you are being questioned.