Ultrafast sintering of dental zirconia: composition-processing-property relationships with high-throughput fail-fast screening

牙科氧化锆的超快烧结：成分-加工-性能关系与高通量快速失败筛选

• 批准号: 10792738
• 负责人: Liangbing Hu
• 金额: $ 48.41万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-06 至 2028-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10792738
• 关键词: 3D Print; Address; Air; Attention; Ceramics; Chemicals; Clinical; Crowns; Dental; Dental Porcelain; Dental Prosthesis; Development; Dimensions; Elements; Engineering; Ensure; Environment; Fatigue; Fracture; Goals; Healthcare; Heating; Implant; Industry; Knowledge; Laboratories; Longevity; Mechanics; Methodology; Microscopy; Modeling; Motion; Optics; Oral cavity; Patients; Physics; Porosity; Powder dose form; Procedures; Property; Prosthesis; Protocols documentation; Quality of life; Radiation; Replica Techniques; Research; Resistance; Resolution; Roentgen Rays; Science; Silicones; Source; Speed; Stress Fractures; Structure; Techniques; Technology; Temperature; Testing; Time; Vacuum; Visit; attenuation; clinical practice; clinically relevant; cold temperature; cost; digital; experience; fabrication; improved; innovation; knowledge base; materials science; mechanical properties; metallicity; next generation; novel; restoration; screening; yttria; zirconium oxide

Project Summary/Abstract Conventional sintering (CS) protocols produce high quality zirconia restorations suitable for a wide range of indications. However, CS requires a firing cycle of 4 – 10 h, a bottleneck in digital dental workflow precluding zirconia from chairside applications. Current speed sintering (SS) protocols using fast heating (up to 6C/s) in an induction furnace can reduce sintering times to 0.3 – 0.5 h. However, because of inefficiency of convective heat transfer, leading to temperature inhomogeneity, SS produces microstructures with higher porosities, thus compromising zirconia translucency and strength. In addition, non-uniform densification raises concerns about chemical and dimensional stability, internal fit and marginal adaptation of restorations. As a result, SS is largely limited to the fabrication of single-unit crowns from 4 mol% yttria stabilized zirconia (4YSZ). Accordingly, the long-term goal is to drastically increase sintering speed (on the order of 60 s) while maximizing mechanical and optical properties of dental zirconia (exceeding those of the SS- and CS-YSZ) by implementing novel UFS technologies. The overall objectives of this proposal are to (1) establish composition and time-temperature- transformation (TTT) relationships to guide material selections for various industries and sectors, with special attention to the optimization of strength and translucency of YSZ for dental applications; and (2) demonstrate improved dimensional, long-term chemical and structural stabilities pertaining to the quality and longevity of UFS-YSZ restorations relative to SS and CS. The central hypothesis is that novel UFS methodology will dramatically increase time efficiency of digital workflow while optimizing zirconia properties and expanding the range of indications for single-visit treatments. This hypothesis follows directly from preliminary results and a state-of-the-art material science knowledge base. To test this hypothesis, we will pursue 3 specific aims: (1) To characterize the properties of yttria stabilized zirconia using ultrafast sintering technology in conjunction with high-throughput fail-fast screening; (2) To determine the resistance to low temperature degradation and fatigue fracture of ultrafast sintered zirconia relative to current speed and conventional sintering; and (3) To evaluate the dimensional stability, internal fit, and marginal adaptation of ultrafast sintered 3-unit fixed dental prostheses relative to current speed and conventional sintering. The approach is innovative because it departs completely from the current furnace-sintering concept by using Joule heating elements with more effective radiation and conduction heat transfer. The proposed research is significant because it addresses current challenges in poor material properties associated with SS and the long sintering time of CS. Such an approach will improve the efficiency and accuracy of restorative procedures to provide more treatment options and better patient experience, thus improving quality of life and reducing cost to the patient.

项目概要/摘要 传统的烧结 (CS) 方案可生产适用于各种场合的高质量氧化锆修复体 然而，CS 需要 4 – 10 小时的烧制周期，这是数字牙科工作流程中的一个瓶颈。 椅边应用中的氧化锆采用快速加热（高达 6°C/s）的当前速度烧结 (SS) 协议。 感应炉可将烧结时间缩短至 0.3 – 0.5 小时，但由于对流效率低下。 热传递，导致温度不均匀，SS产生具有更高孔隙率的微观结构，从而 此外，不均匀的致密化也会影响氧化锆的半透明度和强度。 因此，SS 很大程度上取决于修复体的化学稳定性和尺寸稳定性、内部配合和边缘适应性。 仅限于用 4 mol% 氧化钇稳定的氧化锆 (4YSZ) 制造单个牙冠。 长期目标是大幅提高烧结速度（大约 60 秒），同时最大限度地提高机械性能和 通过实施新型 UFS 实现牙科氧化锆的光学特性（超过 SS-和 CS-YSZ） 该提案的总体目标是（1）确定成分和时间-温度- 转型 (TTT) 关系，指导各个行业和部门的材料选择，特别是 关注牙科应用中 YSZ 的强度和半透明度优化；以及 (2) 证明 改善与质量和寿命相关的尺寸、长期化学和结构稳定性 相对于 SS 和 CS 的 UFS-YSZ 恢复 中心假设是新的 UFS 方法将。 显着提高数字工作流程的时间效率，同时优化氧化锆特性并扩展 单次就诊治疗的适应症范围直接来自初步结果和预测。 为了检验这一假设，我们将追求 3 个具体目标：(1) 使用超快烧结技术并结合氧化钇稳定氧化锆的特性来表征 (2) 测定耐低温退化和疲劳性能 超快烧结氧化锆相对于当前速度和传统烧结的断裂；以及 (3) 评估 超快烧结三单元固定假牙的尺寸稳定性、内部配合和边缘适应性 相对于当前的速度和传统的烧结，该方法是创新的，因为它完全不同。 从当前的熔炉烧结概念出发，使用焦耳加热元件，具有更有效的辐射和 传导传热的研究意义重大，因为它解决了当前贫困问题的挑战。 与 SS 相关的材料特性和 CS 的长烧结时间将改善这种方法。 恢复程序的效率和准确性，以提供更多的治疗选择和更好的患者 体验，从而提高生活质量并降低患者的费用。