Marcio Cajazeira Aguiar1, Victor E Arana-Chavez. 1. Division of Oral Biology, School of Dentistry, University of São Paulo, Av. Prof. Lineu Prestes 2227, Cidade Universitaria, 05508-900 São Paulo, SP, Brazil.
Abstract
OBJECTIVE: Although the general mechanisms of dentinogenesis are understood, several aspects regarding tertiary dentine formation still deserve investigation, especially regarding the presence and distribution of some noncollagenous matrix proteins. As dentine matrix protein 1 (DMP 1) is present in primary dentine, it is possible that this protein may also be present in the dentine matrix secreted after injury, but there are no immunocytochemical studies attempting its detection in tertiary dentine. The aim of this study was to examine the ultrastructural immunolocalization of DMP 1 in the tertiary dentine after extrusion of the rat incisor. STUDY DESIGN: Upper incisors were extruded 3mm and then repositioned into their sockets. After several periods, the incisors were fixed and processed for transmission electron microscopy and for immunocytochemistry for DMP 1. RESULTS: Extrusion yielded both types of tertiary dentine, which varied in aspect and related cells. DMP 1 was found in the mineralized matrix of all types of dentine, presenting high affinity for collagen, but rare colloidal gold particles over predentine. DMP 1 was evident in the supranuclear region and inside the nucleus of some odontoblast-like cells. CONCLUSION: The observed association between DMP 1 and collagen seem to be essential for reactionary and reparative dentine formation. Copyright 2010 Elsevier Ltd. All rights reserved.
OBJECTIVE: Although the general mechanisms of dentinogenesis are understood, several aspects regarding tertiary dentine formation still deserve investigation, especially regarding the presence and distribution of some noncollagenous matrix proteins. As dentine matrix protein 1 (DMP 1) is present in primary dentine, it is possible that this protein may also be present in the dentine matrix secreted after injury, but there are no immunocytochemical studies attempting its detection in tertiary dentine. The aim of this study was to examine the ultrastructural immunolocalization of DMP 1 in the tertiary dentine after extrusion of the rat incisor. STUDY DESIGN: Upper incisors were extruded 3mm and then repositioned into their sockets. After several periods, the incisors were fixed and processed for transmission electron microscopy and for immunocytochemistry for DMP 1. RESULTS: Extrusion yielded both types of tertiary dentine, which varied in aspect and related cells. DMP 1 was found in the mineralized matrix of all types of dentine, presenting high affinity for collagen, but rare colloidal gold particles over predentine. DMP 1 was evident in the supranuclear region and inside the nucleus of some odontoblast-like cells. CONCLUSION: The observed association between DMP 1 and collagen seem to be essential for reactionary and reparative dentine formation. Copyright 2010 Elsevier Ltd. All rights reserved.
Authors: Weibo Zhang; Ivy Pruitt Ahluwalia; Robert Literman; David L Kaplan; Pamela C Yelick Journal: J Biomed Mater Res A Date: 2011-04-11 Impact factor: 4.396