Some people who use teeth whiteners may experience tooth sensitivity. That happens when the peroxide in the whitener gets through the enamel to the soft layer of dentin and irritates the nerve of your tooth. In most cases the sensitivity is temporary. You can delay treatment, then try again.
Federal prison. A federal prison is operated under the jurisdiction of a federal government as opposed to a state or provincial body. Federal prisons are used for convicts who violated federal law (U.S., Mexico), inmates considered dangerous (Brazil), or those sentenced to longer terms of imprisonment (Canada).
The federal-prison.org sentence calculator shows the total time that an inmate can expect to serve in federal prison assuming that they behave and are awarded all Good Conduct Time for which they are eligible. Some of this time may be spent in a halfway house. All inmates are to be considered for up to 12 months of halfway house time.