【作者】 岳雪涛；

【导师】 孙康宁；

【作者基本信息】 山东大学 ， 材料学， 2014， 博士

【摘要】 羟基磷灰石(HAP)具有良好的生物活性和生物相容性,是人类的牙齿和骨骼的主要无机矿物组成,在生物材料中占有重要的地位。近年来科技工作者已经合成了多种形态的HAP材料,例如：HAP非晶材料,HAP微球材料,HAP介孔材料,HAP晶须材料,HAP纤维材料等。由于临床上需要大量的人体硬组织替代材料,及人体植入体,而植入体与人体组织物理化学属性并不相同,需要在植入体的外面涂覆一层生物相容性好的HAP材料,目前常见的植入体材料包括：钛基合金、不锈钢、生物陶瓷等。人们龋病的常见性和多发性引起人们的重视,对牙釉质进行原位仿生再矿化是当前研究的热点内容。本文分别采用化学沉淀法、模拟体液法、共沉淀法、明胶凝胶法制备了普通羟基磷灰石粉体、磁性羟基磷灰石粉体、板条状氟羟基磷灰石粉体。以硫酸亚铁为添加剂,与HAP共沉淀,可以制备出磁性羟基磷灰石,晶粒细小分散性很好,有作为靶向载药材料的潜力。设计了一种新的方法来制备羟基磷灰石微球,利用在化学沉淀法中制备的HAP粉体制备了一定pH值的悬浊液,通过调节pH值制备了HAP中空微球,HAP中空有核微球,HAP实心微球。研究了硬脂酸铝、十六胺、十二烷基硫酸钠和山梨醇对羟基磷灰石晶体生长的影响,反应原料为氯化钙和磷酸氢二钠,其反应初始m(Ca)/m(P)为5：3,按照不同浓度加入外加剂,研究在多种介质下HAP颗粒的生长,并对晶粒进行了表征。采用高能球磨法,以分析纯的Ti粉和AI粉为原料,制备了金属间化合物Ti3Al,并以在模拟体液中制备的HAP粉体为基体,Ti3Al为第二相,制备了Ti3Al/HAP复合材料,烧结温度分别为1000℃、1050℃和1100℃,并对其进行力学性能检测.力学测试结果显示Ti3Al/HAP复合材料的力学性能并没有显著提高,抗弯强度均比纯HAP陶瓷低,而烧结温度为1100℃,Ti3Al掺入量为1%的试样断裂韧性值最高。分别在硅片、Ti3Al/HAP复合材料和牙切片上进行了涂层制备。研究结果显示通过电泳沉积法可以在硅片上制备出HAP的涂层,涂层的晶粒生长复合台阶式生长,每当台阶沿着晶面扫过一次,则晶体就长大了一层。以螯合剂EDTA-2Na为媒介,可分别在Ti3Al/HAP复合材料和牙釉质的表面制备出钙磷矿物涂层,涂层由六方棱柱状晶体组成,适当延长矿化时间和矿化温度,制备的涂层晶粒垂直于基底材料平行排列。采用酸性糊剂法可以在牙釉质的表面制备出一层致密的由细小晶粒组成的涂层,在一定pH值范围内,该涂层与酸性糊剂的pH值大小无关。更多还原

【Abstract】 Hydroxyapatite (HAP) is the mainly inorganic composition of bones and teeth of humans and animals, with good bioactivity and biocompatibility. It can combine with bones firmly and is the main substitute materials of human bone s and teeth. As the growing acknowledgement of hydroxyapatite research in recent years, people have synthesized various kinds of HAP crystal structures and coatings. For instance, HAP non-crystalline materials, HAP microspheres materials, HAP mesoporous materials, HAP whisker s, HAP fibers and etc. For the sake of great need of human implant to replace human tooth and bone, researcher have to work hard to cover the implant with better biocompatible and bioactive coating, which stay in human body very well. Now the most frequently used base materials include titanium alloy, stainless steel, and bioceramics. Dental caries is a kind of conmmon and multiple disease, and people pay attention to this research field. Now In-situ biomimetic remineralization research of enamel is very hot.In this paper, common HAP powder, magnetic HAP nanoparticles lath like FAP were prepared by the methods of chemical deposition, in SBF, coprecipitation and gel. When FeSO4was added into the solution it could be turn into Fe2O3, which would bring magnetism to the HAP powder. The crystals in magnetism powder is very small and loose which could be used as carrier of drug. We also have design a new way to produce HAP microspheres. In the HAP suspension with different pH value, hollow sphere, hollow sphere with core and compact microspheres were produced.The effect of additive on the crystal growth of HAP were researched, which include Sodium stearate, cetylamine, Sodium dodecyl sulfate and Sorbitol, and the raw materials include calcium nitrate and disodium hydrogen phosphate. At the beganing of experiment the ratio of Ca/P was5:3. The different degree of additive was added into the solution and the growth of HAP crystal were studied and characterized.We also prepared Ti3AI/HAP composite by sintered at1000℃,1050℃and 1100℃。At first the intermetallic compound Ti3AI was prepared by mixed and ball mill. Then added the intermetallic compound Ti3AI to HAP made in SBF, the compound powder was ready for the sintered. Mechanical test result display the with the addition of Ti3AI the bend strength is reduced and the most value of fracture strength was detected in sample which was sintered under1100℃, and the amount of Ti3AI is1%.This paper also illustrated a possible way to produce coating on the surface of Ti3Al/HAP. The result of research experiment show that the HAP coating could grow on the surface of Si substrate, and the way of crystal growth is accord with the step growth theory. When the step pass through the crystal surface once time, the crystal grow bigger. We also prepared HAP coating on the Ti3Al/HAP composite and dental enamel with EDTA-2Na. By the SEM images the crystal of coating were observed which is a typical apatite hexagonal structures. The simple chemical method could produce enamel-like structure with prism and interprism under near-physiological conditions. The newly growth layerwas quite close to the natural enamel in chemical components, microstructure, and nanomechanical properties. The newly grown crystals have bigger size and more F content than the crystals of enamel, so it can be concluded that the newly grown layer have the better ability to resist against stronger acidic solution than that of the natural enamel. For the reason that fluoridated hydroxyapatite has excellent biocompatibility, it is a promising approach that reconstructing the early caries lesion using this simple chemical method.更多还原