Donor hair is usually not permanent.
"From Times Online
January 28, 2010
Latest hair-raising scandal of Italian leader Silvio Berlusconi
Richard Owen in Rome
Piero Rosati, the surgeon who carried out hair transplants on the Prime Minister in 2004 and 2005, was quoted as suggesting that Mr Berlusconi’s hair had fallen out because of stress. It remains unclear however whether the reappearance of the hair two days later was due to emergency reinsertion of follicles or a toupee."