A study of hard tissue regeneration around on the periodontal ligament in tooth replantation using dental pulp cells

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K20467
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Conservative dentistry
• Research Institution: The Nippon Dental University
• Principal Investigator: YAMADA Rie 日本歯科大学, 新潟生命歯学部, 非常勤講師 (70772151)
• Research Collaborator: MINATO Hanae
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 歯髄 / コラーゲンゲル / 再生医療 / 移植 / 細胞培養

Outline of Final Research Achievements

The purpose of this study is searching for differentiation the dental pulp-derived cells possess the potential to dentin and periodontal tissue.First, primary culture of rat incisor dental pulp tissue was performed.The dentin pieces were encapsulated with dental pulp-derived cells-containing collagen gel and transplanted subcutaneously in the back of nude mice. 6 weeks later nude mice were sacrificed and observed.New blood vessels and odontoblast-like structures were observed around the transplanted dentin pieces.
Next, the mesial root canal of the maxillary first molar of the rat was filled with the retrograde root canal filling material,and the periodontal ligament was removed. Dental pulp-derived cells-containing collagen gel was injected into the extraction socket and the tooth were returned. 2 weeks and 4 weeks later, rats were sacrificed and observed. New bone-like tissue was observed the apical area, and collagen fibers entering cementum near the cervical area were observed.

Free Research Field

歯内療法学

Academic Significance and Societal Importance of the Research Achievements

近年、乳歯や永久歯の歯髄幹細胞を利用した再生医療の開発が進められており、将来の再生医療分野で期待される。本研究は、ラットの歯髄から得た細胞が象牙質および歯根膜組織に分化する可能性を検討する目的で行った。培養した細胞を含有させたコラーゲンゲルに象牙質片を被包させてヌードマウスに移植すると、象牙芽細胞様構造が観察され、象牙質分化マーカーの発現がみられた。またラット第一臼歯を抜歯し、細胞含有コラーゲンゲルを注入し再植すると、歯頸部分でコラーゲン線維が観察され、根尖部分では新生骨様組織がみられた。
以上から移植した歯髄細胞がコラーゲンゲルを足場とし、生体組織との相互作用が起こり分化した可能性が示された。