title: Collagen analysis in human tooth germ papillae.
abstract: The extracellular matrix (ECM) performs a very important role in growth regulation and tissue differentiation and organization. In view of this, the purpose of this study was to analyze the collagen, the major organic component of dental pulp ECM, in papillae of human tooth germs in different developmental phases. The maxillas and mandibles of 9 human fetuses ranging from 10 to 22 weeks of intrauterine life were removed and 16 tooth germs (1 in the cap stage, 8 in the early bell stage and 7 in the late bell stage) were obtained. The pieces were processed for histological analysis and stained with hematoxylin-eosin, Masson's Trichrome and picrosirius staining technique. Both types of collagen in the dental papilla were only detected by the picrosirius staining technique under polarized light microscopy. Type III collagen was detected in all specimens. Type I collagen was present in focal areas of the dental papilla only in some specimens. In conclusion, the findings of this study showed that type III collagen is a regular component of the papillae of human tooth germs whereas type I collagen is present in a significantly lesser amount.
authors.affiliation: Department of Endodontics, School of Dentistry, University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Ivete Jorge
authors.initials: IJ
authors.lastname: Abrahão
authors.forename: Manoela Domingues
authors.initials: MD
authors.lastname: Martins
authors.forename: Emílio
authors.initials: E
authors.lastname: Katayama
authors.forename: João Humberto
authors.initials: JH
authors.lastname: Antoniazzi
authors.forename: Angelo
authors.initials: A
authors.lastname: Segmentilli
authors.forename: Márcia Martins
authors.initials: MM
authors.lastname: Marques
mesh_terms: D001391:Azo Compounds; D003094:Collagen / Q000032:analysis*; D024042:Collagen Type I / Q000032:analysis; D024061:Collagen Type III / Q000032:analysis; D004396:Coloring Agents; D003771:Dental Papilla / Q000737:chemistry / Q000648:ultrastructure*; D003782:Dental Pulp / Q000196:embryology; D005109:Extracellular Matrix / Q000648:ultrastructure; D005333:Fetus; D005865:Gestational Age; D006801:Humans; D009805:Odontogenesis / Q000502:physiology; D014083:Tooth Germ / Q000737:chemistry / Q000648:ultrastructure
chemical_list: D001391:Azo Compounds; D024042:Collagen Type I; D024061:Collagen Type III; D004396:Coloring Agents; C009798:C.I. direct red 80; D003094:Collagen