Detection of Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella intermedia, and Prevotella nigrescens in chronic endodontic infection - Tomazinho, Luiz Fernando; Avila-Campos, Mario Julio (Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology and Endodontics, 2007)