Dentist Goska Popiel (L) and dental hygienist Yvonne Mustapha give Marian Gogu a filling in a mobile clinic at one of nine temporary regional centres for the homeless, opened during the Christmas season by the charity Crisis, in east London December 23, 2011. The centres were opened as an alternative for services which close over the Christmas holidays. REUTERS/Luke MacGregor (BRITAIN - Tags: POLITICS HEALTH)