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).
Definition of prison. Examples of prison in a sentence. The state plans to build two more prisons. He was in prison at the time. If caught, they're all going to prison. She was sent to prison for robbery. He was released from prison. He's scheduled to get out of prison next month.