A sex offender is any person who resides or works in the Commonwealth and who has been convicted of a sex offense, or who has been adjudicated as a youthful offender or as a delinquent juvenile by reason of a sex offense, or a person released from incarceration or parole or probation supervision or custody with the department of youth services for such a conviction or adjudication, or a person who has been adjudicated a sexually dangerous person or a person released from civil commitment on or after August 1, 1981.