Interleukin-4 gene polymorphisms and its relation to periodontal disease in a Brazilian population of African heritage - Pontes, Carla Cruvinel; Gonzales, Jose R.; Novaes Júnior, Arthur Belém; Taba Júnior, Mário; Grisi, Márcio Fernando de Moraes; Michel, Joerg; Meyle, Joerg; Souza, Sérgio Luis Scombatti de (Journal of Dentistry, 2004)