钛铸造表面改性改善钛-瓷结合的研究

Titanium（Ti）is known for its high corrosion resistance and good biocompatibility. It has therefore been widely used as a material for implants, simple crowns, fixed partial dentures, and removable partial dentures. However, the adhesion between titanium and dental porcelain is poor when compared to typical metal-ceramic systems, because Ti is rapidly oxidized when the temperature above 800℃,providing a thick and loosened titanium oxide layer on the Ti surface while porcelain fusing, so that the Ti-porcelain restoration has limited application. The purpose of this investigation is to study the characteristics of the SiO2 or Al2O3 et al coating on Ti surface which is fabricated by cast method using high temperature reactivity and vacuum casting circumstance of Ti cast process, to form Ti-Si or Ti-Al et al intermediate layer on the Ti surface. First, the inner investments including SiO2 or Al2O3 et al will be studied, Second, rectangular wax patterns (25mm×3mm×0.5mm) is prepared, one side of which is coated with inner investment materials about 0.5mm thick, without inner investment material coated is used as controls. These patterns are invested with the author has successfully developed ZrO2 based investment material and cast with pure titanium routinely. After cleaned, these castings surface is analyzed with XRD and SEM/EDS to determine the mixed layer structure and composition, the mixed layer will bond with porcelain glass phase in the formation of chemical bond. Third, porcelain firing is made according to its manufacturers' instructions, successive porcelain layers are built up in dimensions of 8mm×3mm×1mm at the center of each specimen. Ti-porcelain Interface is also analyzed with SEM/EDS, Ti-porcelain specimens are tested in three point bending at a crosshead speed of 1.5mm/min according to ISO 9693 requirements. According to the results, to discuss the most effective coating of Ti surface modofication by cast, in order to expand the titanium porcelain restoration in restorative dentistry, and improve people's quality of life.

钛具有良好的生物相容性，但在高温下与氧有极高的亲和力，影响了钛-瓷的结合，使钛-瓷修复体的应用受到限制。本课题首先以SiO2或Al2O3或瓷粉等为主要成分研制烤瓷用内包埋材料，然后将其涂在铸造蜡型要烤瓷的一侧，用笔者已研制成功的钛铸包埋材料包埋铸造，通过铸造的方式利用钛在高温下的化学活泼性，使烤瓷用内包埋材料主要成份在无氧的环境下，与熔化的钛反应，在铸造体烤瓷一侧形成Ti- SiO2或Ti-Al2O3或Ti- Si或Ti-Al或Ti-瓷粉等混合层，将铸造体分别经超声波清洗、喷砂、酸及碱不同的处理后，对混合层表面、断面电镜观察及元素分析，确定混合层的结构与成分，该混合层能与烤瓷中的玻璃相形成化学性结合，常规烤瓷后电镜观察、分析断面结构，并做三点弯曲试验，探讨钛铸造表面改性改善钛-瓷结合的有效方法，以便扩大钛-烤瓷修复体在口腔修复中的应用，提高人民的生活质量。

我国即将进入老龄化社会，对口腔修复体的需求也在不断的增加。钛具有良好的生物相容性，但在高温下与氧有极高的亲和力，影响了钛-瓷的结合，使钛-瓷修复体的应用受到限制。.另一方面，随着修复材料日新月异的发展，氧化锆全瓷大有取代钛-瓷修复的趋势，但由于氧化锆的惰性使其粘接仍存在问题。我们还创新性地研究了负压对口腔修复体粘接的影响。.一、钛铸造表面改性改善钛-瓷结合.1.正硅酸乙酯作为结合剂，SiO2和 SiO2-ZrO2为有效成分的内包埋材料涂在蜡型的烤瓷侧，铸造过程中熔融钛与SiO2或 SiO2-ZrO2发生反应，钛铸表面形成Ti-SiO2和Ti-SiO2-ZrO2过度层，Si的存在有效改善了钛-瓷的结合性能，况且，Ti-SiO2和Ti-SiO2-ZrO2过度层的存在使铸钛修复体烤瓷前不需要预氧化处理。.2.用30, 60%的Al2O3作为内包埋材料主要成分，铸钛表面形成了Ti-Al2O3混合层，30%组有效改善钛-瓷的剪切强度。.3.用粘接瓷、体瓷以及TiO2作为内包埋材料，铸钛表面反应剧烈，严重影响其精密度；正硅酸乙酯水解铸钛表面制备硅涂层，但量太少。 .适当量的SiO2或Al2O3做为内包埋材料有效成分，可有效改善钛-瓷的结合，为临床钛-瓷修复体的制作提供一种简单有效的方法。.二、负压对钛及氧化锆修复体粘接性能的影响.创新性地将负压用于钛及氧化锆修复体粘接，粘接面涂粘接剂后施以负压，使修复体与粘接剂界面以及粘接剂内部的气体溢出，常压后，可使修复体与粘接剂的粘接界面更加密合。从而改善了钛及氧化锆与树脂粘接剂的粘接性能，延长使用寿命，降低粘接界面的微渗漏。.三、喷砂对氧化锆陶瓷粗糙度以及锆-瓷结合的影响.氧化锆强度高，传统喷砂对其粗糙度改变较小，并且易造成氧化锆的相变、裂纹等。在氧化锆致密烧结前喷砂，有效提高了氧化锆的表面粗糙度，避免了相变和裂纹，并提高了氧化锆-瓷的粘接强度。为临床改善锆-瓷的粘接提供了一种有效方法。.四、氧化锆原为生成多晶粒改善氧化锆的粘接性能.致密烧结前氧化锆坯体表面与HF反应，生成ZrF4，再与CaCl2反应生成ZrOCl2，经碱热处理后生成Zr(OH)4、伴随氧化锆的致密烧结，其表面原位生成氧化锆多晶粒，改善了氧化锆与树脂粘接剂粘接性能,也有望改善锆-瓷的粘接。提供一种改善氧化锆粘接的有效途径。