Composition and role of cement line on the resorption surface of the tooth.

2000 Fiscal Year Final Research Report Summary

• Project/Area Number: 11671825
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Morphological basic dentistry
• Research Institution: Mastumoto Dental University
• Principal Investigator: SAHARA Noriyuki Matsumoto Dental University, Associate Professor, 歯学部, 助教授 (70064699)
• Project Period (FY): 1999 – 2000
• Keywords: Enamel / Cement line / Tooth resorption / Repair / TRAP / Shedding / Odontoclasts / Deciduous teeth

Research Abstract

The present study suggested that a basophilic layer, cement line, on the previously resorbed enamel surface observed in the transitional phase may play a important role in the process of tooth resorption-sequence. The cement line on the resorbed enamel surface gradually matured and mineralized towards the end of the transitional phase, and ultimately formed reversal line that could be found between the resorbed enamel and the newly formed cementum-like tissue. Base on these results it can be assumed that the components of the basophilic layer on the resorbed dentine surface (cement line and reversal line) might be consisted from multiple sources : (1) secretory products of the odontoclasts, (2) circulating various plasma proteins, (3) secretory products mononuclear phagocytic cells on the resorbed surface and (4) secretary products of cementoblast-like cells. And further, it can be also postulated that these various components in this layer may also play multiple roles in various stages of tooth resorption-repair sequence : (a) Some of them will act as coupling factors to promote the proliferation and differentiation of cementoblast-like cells. (b) Some of them may serve to influence early matrix organization and mineralization. (c) They will be act as promoters for the interfacial adhesion between different mineralized tissues.