Division of Oral Biology, School of Dentistry, University of São Paulo, Av. Prof. Lineu Prestes 2227, Cidade Universitaria, 05508-900 São Paulo, SP, Brazil.
Arch Oral Biol. 2010 Mar;55(3):210-4. doi: 10.1016/j.archoralbio.2010.01.005. Epub 2010 Feb 6.
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.
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.
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.
The observed association between DMP 1 and collagen seem to be essential for reactionary and reparative dentine formation.
尽管牙本质发生的一般机制已被理解，但仍有几个方面值得研究，特别是关于一些非胶原蛋白基质蛋白的存在和分布。由于牙本质基质蛋白 1（DMP1）存在于原发性牙本质中，因此该蛋白也可能存在于损伤后分泌的牙本质基质中，但尚未有免疫细胞化学研究试图检测三进制牙本质中的 DMP1。本研究旨在观察大鼠切牙挤出后三进制牙本质中 DMP1 的超微结构免疫定位。
将上颌切牙挤出 3mm，然后重新定位到其牙槽中。经过一段时间后，将切牙固定并进行透射电子显微镜和 DMP1 免疫细胞化学处理。
挤出产生了两种类型的三进制牙本质，其形态和相关细胞有所不同。DMP1 存在于所有类型牙本质的矿化基质中，与胶原具有高亲和力，但在前期牙本质中很少有胶体金颗粒。DMP1 在一些成牙本质细胞的核上区和核内可见。
观察到的 DMP1 与胶原之间的关联似乎对反应性和修复性牙本质形成至关重要。
