Ceramic scaffolds with engineered topography and chemistry

具有工程形貌和化学特性的陶瓷支架

基本信息

批准号：
8590115
负责人：
Isabelle L Denry
金额：
$ 37.37万
依托单位：
UNIVERSITY OF IOWA
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-02-01 至 2017-01-31
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant): The research proposed in this application is directed at developing novel ceramic scaffolds that are bioresorbable, bioactive, osteoconductive and exhibit high strength. These goals will be achieved through stepwise engineering of the ceramic microstructure, scaffold architecture, micro and nanotopography and surface chemistry. The rationale is that there is currently no synthetic scaffold material that is bioactive, resorbable and exhibits biologically compatible compressive strength. We will first investigate the crystallization kinetics and mechanical properties of sintered niobium- doped fluorapatite (FAp) ceramics with the aim of developing a highly crystalline ceramic with nanosized FAp crystals (Aim 1). We will select the best composition with niobium additions that will induce phase separation, lead to the crystallization of nanosized crystals and high crystallinity. We will then prepare FAp ceramic scaffolds using a carefully engineered approach that combines a pre-coating step, a glazing step and a chemical etching step (Aim 2). We postulate that optimization of the scaffold architecture will lead to superior mechanical properties and that the chemical etching step will promote a complex three-dimensional surface micro and nanotopography later stimulating contact osteogenesis. The effect of ion-exchange on surface chemistry, solubility and bioactivity of the scaffolds will be tested in Aim 3. The overall rationale is that strontium substitution in the apatite structure will increase solubility and bioactivity. Finally, the resorption and bone regeneration ability of the scaffolds will be tested in vivo using a rat calvarial critical defect model and a combination of state of the art in vivo micro-computed tomography and histopathology (Aim 4). The hypotheses tested are that the surface chemistry and topography of the scaffolds will enhance bone regeneration and that the resorption rate will be compatible with the rate of bone regeneration.

描述（由申请人提供）：本申请中提出的研究旨在开发可生物可吸收，生物活性，破骨传导性和表现高强度的新型陶瓷支架。这些目标将通过对陶瓷微结构，脚手架结构，微型和纳米形态以及表面化学的逐步工程来实现。理由是目前尚无生物活性，可吸收并具有生物学兼容的抗压强度的合成支架材料。我们将首先研究烧结的Niobium掺杂的氟磷灰石（FAP）陶瓷的结晶动力学和机械性能，目的是开发带有纳米化FAP晶体的高度结晶陶瓷（AIM 1）。我们将选择最佳的组成，并添加氮化物，从而诱导相分离，导致纳米化晶体的结晶和高结晶度。然后，我们将使用精心设计的方法来准备FAP陶瓷支架，该方法结合了预涂层步骤，玻璃的步骤和化学蚀刻步骤（AIM 2）。我们假设脚手架结构的优化将导致优质的机械性能，并且化学蚀刻步骤将促进复杂的三维表面微型和纳米造影，然后刺激接触式成骨。离子交换对脚手架表面化学，溶解度和生物活性的影响将在AIM 3中进行测试。总体理由是，磷灰石结构中的锶取代将提高溶解度和生物活性。最后，脚手架的吸收和骨再生能力将在体内使用大鼠刻痕临界缺陷模型和体内微型计算机层析成像和组织病理学中的最新状态进行体内测试（AIM 4）。测试的假设是脚手架的表面化学和地形将增强骨骼再生，并且吸收率将与骨再生速率兼容。