title: Development of the oxytalan fiber system in the periodontal space of rat incisors.
abstract: The present study clarifies developmental organization of the oxytalan fiber system in the periodontal space of both the enamel (labial) and cementum (lingual) sides of rat incisors. The number of oxytalan fibers per unit area (μm(2)) was counted in rat incisors at stages of embryonic day 20 (E20) to postnatal day 35 (P35). Oxytalan fibers in the periodontal space of the enamel side were apt to decrease in number during the postnatal period, whereas their number remained almost unchanged on the cementum side during the developmental period. When the incisor emerged through the gum at P11, thinner oxytalan fibers distributed in the apical growing periodontium of the cementum side seemed to be fused with one another to become thicker fibers as has been reported for rat molars (Inoue et al., 2012). Thus, the oxytalan fiber system in the periodontal space represented significant differences in its distributional density between the enamel and cementum sides after E23. At the stage of P35, oxytalan fibers presented significantly denser distribution in all territories of the periodontal ligament of the cementum side versus the enamel side. The present findings claim that the oxytalan fiber system might bind the tooth to the periodontal ligament and provide equilibrium of vascular system and control of blood flow in the periodontal ligament of the cementum side, while it might exclusively regulate the high level of physiologically adapted vasculature in the periodontal space of the enamel side.
authors.affiliation: Research Center of Electron Microscopy, School of Dental Medicine, Tsurumi University, Yokohama 230-8501, Japan. Electronic address: inoue-k@tsurumi-u.ac.jp.
authors.forename: Kouji
authors.initials: K
authors.lastname: Inoue
authors.forename: Yaiko
authors.initials: Y
authors.lastname: Hara
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Kuroda
authors.forename: Tetsuji
authors.initials: T
authors.lastname: Sato
mesh_terms: D000818:Animals; D003739:Dental Cementum / Q000648:ultrastructure; D003743:Dental Enamel / Q000254:growth & development / Q000648:ultrastructure; D016326:Extracellular Matrix Proteins / Q000502:physiology*; D005260:Female; D005881:Gingiva / Q000254:growth & development* / Q000648:ultrastructure*; D007150:Immunohistochemistry; D007180:Incisor / Q000254:growth & development* / Q000648:ultrastructure*; D008297:Male; D046529:Microscopy, Electron, Transmission; D010513:Periodontal Ligament / Q000502:physiology; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar; D000683:Serum Amyloid P-Component / Q000378:metabolism
chemical_list: D016326:Extracellular Matrix Proteins; D000683:Serum Amyloid P-Component; C437744:oxytalan
keywords: Cementum side; Development; Enamel side; Incisor; Oxytalan fiber system; Periodontal space; Rat