Department of Civil, Material, and Environmental Engineering, University of Illinois at Chicago, Chicago, IL, USA.
Department of Restorative Dentistry, University of Illinois at Chicago, College of Dentistry, Chicago, IL, USA.
Dent Mater. 2024 Nov;40(11):1823-1831. doi: 10.1016/j.dental.2024.08.007. Epub 2024 Aug 22.
Implant treatment is provided to individuals with normal, idealized masticatory forces and also to patients with parafunctional habits such as grinding, clenching, and bruxing. Dental erosion is a common increasing condition and is reported to affect 32 % of adults, increasing with age. This oral environment is conducive to tribocorrosion and the potential loss of materials from the implant surfaces and interfaces with prosthetic components. Although several fretting-corrosion studies have been reported, until now, no study has simulated clinically relevant micromotion. Therefore, our aim is to investigate fretting-corrosion using our new micro-fretting corrosion system, simulating clinical conditions with 5 µm motion at the implant-abutment interface under various occlusal loads and acidic exposures.
We simulated four conditions in an oral environment by varying the contact load (83 N and 233 N) and pH levels (3 and 6.5). The commonly used dental implant material, Grade IV titanium, and abutment material Zirconia (ZrO)/ Grade IV titanium were selected as testing couple materials. Artificial saliva was employed to represent an oral environment. In addition, a standard tribocorrosion protocol was followed, and the pin was controlled to oscillate on the disk with an amplitude of 5 μm during the mastication stage. After the testing, 3D profilometry and scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) were utilized to analyze the worn surfaces. Inductively coupled plasma mass spectrometry (ICP-MS) was also used to measure the metal ion release.
Energy ratios were below 0.2, indicating a fretting regime of partial slip for all groups. Open-circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) were analyzed to compare the electrochemical behavior among groups. As a result, corrosive damage was observed to be more in the Ti4- Ti4 groups than in Zr-Ti4 ones, whereas more mechanical damage was found in the Zr-Ti4 groups than in the Ti4-Ti4 groups. Possible mechanisms were proposed in the discussion to explain these findings.
The results observed from this study might be helpful to clinicians with implant selection. For example, for patients with bruxism, a titanium implant paired with a titanium abutment may be preferable, while patients with GERD may benefit more from a titanium implant paired with a zirconia abutment.
种植治疗既提供给正常、理想化咀嚼力的个体，也提供给磨牙、紧咬牙和研磨等功能紊乱习惯的患者。牙齿酸蚀是一种常见的日益严重的情况，据报道影响 32%的成年人，且随年龄增长而增加。这种口腔环境有利于摩擦腐蚀和种植体表面与修复体部件之间材料的潜在损失。尽管已经有几项微动腐蚀研究报告，但到目前为止，还没有研究模拟临床相关的微运动。因此，我们的目的是使用新的微动腐蚀系统进行微动腐蚀研究，在各种咬合负荷和酸性暴露下，在种植体-基台界面模拟 5 µm 的临床相关微运动，以此来模拟临床条件。
通过改变接触负荷（83 N 和 233 N）和 pH 值（3 和 6.5），我们在口腔环境中模拟了四种情况。常用的牙科种植体材料四级钛和基台材料氧化锆（ZrO）/四级钛被选为测试偶材料。人工唾液被用来代表口腔环境。此外，遵循标准的摩擦腐蚀协议，在咀嚼阶段，将销钉控制在磁盘上以 5 µm 的振幅振动。测试后，使用三维轮廓仪和扫描电子显微镜（SEM）结合能谱（EDS）分析磨损表面。电感耦合等离子体质谱（ICP-MS）也用于测量金属离子释放。
对于所有组，能量比均低于 0.2，表明存在部分滑动的微动状态。开路电位（OCP）和电化学阻抗谱（EIS）分析用于比较各组之间的电化学行为。结果表明，Ti4-Ti4 组的腐蚀性损伤比 Zr-Ti4 组更严重，而 Zr-Ti4 组的机械损伤比 Ti4-Ti4 组更严重。在讨论中提出了可能的机制来解释这些发现。
本研究观察到的结果可能对临床医生选择种植体有帮助。例如，对于磨牙症患者，钛种植体与钛基台配对可能更可取，而胃食管反流病患者可能从钛种植体与氧化锆基台配对中获益更多。
