FORMER Khmer Rouge head of state Khieu Samphan was released from the United Nations-backed Khmer Rouge tribunal yesterday for a dental examination, officials said. Court spokesman Reach Sambath said Khieu Samphan left the prison “to meet with a dentist at Calmette Hospital” for a scheduled appointment before returning to his cell. Khieu Samphan, 79, is awaiting trial along with three other aging leaders of the Khmer Rouge. Their trial on charges of crimes of war, crimes against humanity and genocide is expected to start next year.