Dentin-pulp dynamics of aging teeth

项目总结/摘要 利用牙本质-牙髓复合体再生能力的新策略的引入可能使 人类有可能在一生中保留他们的天然牙齿。研究表明 牙髓干细胞保持非凡的特性，可以为牙科护理提供临床选择 和恢复。然而，老年患者是否也能从这些技术中受益仍是未知数。 nologies。这个项目的长期目标是了解牙齿在整个成人过程中是如何变化的。 为了开发可以保护或增强牙齿健康并允许整个牙齿保持的治疗方法， 寿命本研究的目的是定性分析年轻和老年啮齿动物磨牙的牙本质-牙髓界面， 确定牙本质牙髓复合体的再生能力如何随年龄变化。我们的核心假设 DP间充质、血管和神经支配的年龄相关变化改变了分泌和利用， 牙本质中生物活性蛋白（BPiD）和牙髓衰老的能力，以及 BPiD，随着年龄的增长降低牙齿活力。该项目的基本原理是， 牙齿老化和再生有可能揭示活髓疗法的分子候选者。中央卫生- 将以下列特定目的对假设进行测试：1）鉴定牙本质中分泌的生物活性蛋白， 随年龄变化; 2）分析牙齿随年龄变化。在第一个目标下， 提取老年大鼠，分成根和冠部分，并研磨用于随后的蛋白质组学分析， 牙本质成分。ELISA和/或免疫荧光将验证位置和丰度，以确定- 在损伤和/或再生过程中，使能够调节神经血管反应的感兴趣的分泌蛋白质化。 对于第二个目的，将在3个月和20个月的小鼠中手术损伤小鼠磨牙牙本质，并在24小时内进行分析。 改变时间点以评估：a）使用纳米压痕测定的弹性和硬度; B）矿化体积 和密度;以及c）牙髓神经血管损伤 基于共焦成像的响应。本申请中提出的研究是创新的，因为它有利于 使用几种应用于临床前小鼠模型的技术， 从年轻人到老年人拟议的研究是有意义的，因为它有望确定活髓 治疗和再生牙髓候选人继续研究和未来的临床试验与病人 在生命的不同阶段。最终，这些知识有可能提供新的牙科治疗方法， 患者保持牙齿健康并将其天然牙齿保留到老年。

PROJECT SUMMARY/ABSTRACT The introduction of new strategies harnessing the regenerative capacity of the dentin-pulp complex may make it possible for humans to retain their natural teeth throughout their lifespan. Research has demonstrated that dental pulp stem cells maintain extraordinary characteristics that can provide clinical options for dental care and restoration. However, it remains unknown whether older patients are also able to benefit from these tech- nologies. The long-term goal of this project is to gain an understanding of how teeth change throughout adult- hood in order to develop treatments that can preserve or enhance tooth health and permit retention throughout the lifespan. Our objective is to analyze the dentin-pulp interface in young and old rodent molars to qualitatively determine how the regenerative capacity of the dentin-pulp complex changes with age. Our central hypothesis is that age-related changes to the DP mesenchyme, vasculature, and innervation alter the secretion and avail- ability of bioactive proteins in dentin (BPiD) and that pulpal senescence, in combination with reduced access to BPiD, reduces tooth vitality with age. The rationale for this project is that a detailed scientific framework of tooth aging and regeneration is likely to uncover molecular candidates for vital pulp therapies. The central hy- pothesis will be tested with the following specific aims: 1) Identify secreted bioactive proteins in dentin that change with age; and 2) Analyze age-dependent changes in teeth. Under the first aim, molars from young and old rats will be extracted, divided into root and crown portions, and milled for subsequent proteomic analyses of the dentin composition. ELISA and/or immunofluorescence will verify location and abundance in order to iden- tify secreted proteins of interest that could regulate neurovascular responses during injury and/or regeneration. For the second aim, mouse molar dentin in 3- and 20-month mice will be surgically damaged and analyzed at varying time points to assess: a) elasticity and hardness using nanoindentation assays; b) mineralized volume and density determined by microcomputed tomography (micro-CT); and c) dental pulp neurovascular injury responses based on confocal imaging. The research proposed in this application is innovative because it pro- vides a comprehensive view of how teeth age using several techniques applied to preclinical murine models from young and elderly stages. The proposed research is significant because it is expected to identify vital pulp therapy and regenerative endodontics candidates for continued research and future clinical trials with patients in different stages of life. Ultimately, such knowledge has the potential to offer new dental treatments to help patients maintain their dental health and retain their natural teeth into old age.