Pozhitkov Alex, Lindahl Eric, Chan Daniel C
Division of Research Informatics, City of Hope National Medical Center, Duarte, USA.
Restorative Dentistry, University of Washington School of Dentistry, Seattle, USA.
Cureus. 2023 Dec 4;15(12):e49907. doi: 10.7759/cureus.49907. eCollection 2023 Dec.
Background Titanium dental implants (e.g., Nobel Biocare, Switzerland) are routinely used as support for dental restoration. Titanium has been the material of choice due to its corrosion resistance and ability to integrate with bone. Nevertheless, corrosion and titanium dissolution do occur. Compared to control, peri-implantitis tissue biopsies have been shown to contain high concentrations of dissolved titanium as well as metal particles. Dissolved titanium species have been found to be associated with the structure/diversity of the subgingival plaque microbiome and the extent of global methylation. Of note, peri-implantitis and peri-implant mucositis are common biological complications of implant therapy. Microorganisms and local inflammation together with a gradient of oxygen have been proven to form an electrochemical fuel cell, which generates the current that flows through the body of the titanium implant. Effectively, the fuel cell reduces oxygen and oxidizes titanium that turns into a soluble form. We are proposing a new zirconia-titanium composite implant design whereby the electrical current is disrupted while other properties are still conducive to osseointegration. Methodology Biocompatible zirconia bolts were treated with hydrofluoric acid (HF) and coated with titanium in a vacuum evaporator. The coating was masked with nail polish, and unmasked areas were etched with HF followed by mask removal with a solvent. Microbial challenges were conducted with a volunteer's plaque. Regular implant (control) and the prototype were inserted into simulated peri-implant environments implemented as a fiberglass sleeve immersed into a growth medium. After a five-day growth, samples were taken and HNO digested. Dissolved titanium was evaluated by inductively coupled plasma mass spectrometry. Results Proof-of-concept implant prototypes were successfully created. Vacuum deposition results in reproducible stable titanium coating. The thickness of the titanium coating was estimated using atomic force microscopy. A microbial challenge revealed that compared to the commercial titanium implant, the new implant prototype showed decreased amounts of corrosion-leached titanium. Conclusions We demonstrate a path forward toward a new design of a dental implant, whereby corrosion-induced electrical currents are interrupted resulting in a decreased amount of dissolved titanium.
背景 牙科钛植入物（例如瑞士的诺贝尔生物保健公司生产的产品）通常用作牙齿修复的支撑物。由于钛具有耐腐蚀性以及与骨结合的能力，它一直是首选材料。然而，腐蚀和钛溶解确实会发生。与对照组相比，种植体周围炎组织活检显示含有高浓度的溶解钛以及金属颗粒。已发现溶解的钛物种与龈下菌斑微生物群的结构/多样性以及整体甲基化程度有关。值得注意的是，种植体周围炎和种植体周围黏膜炎是种植治疗常见的生物学并发症。微生物、局部炎症以及氧梯度已被证明会形成一个电化学燃料电池，该电池产生流经钛植入物体的电流。实际上，该燃料电池会使氧还原并氧化钛，使其变成可溶形式。我们提出了一种新的氧化锆 - 钛复合植入物设计，在这种设计中，电流被中断，而其他特性仍有利于骨整合。
方法 生物相容性氧化锆螺栓用氢氟酸（HF）处理，并在真空蒸发器中涂覆钛。涂层用指甲油遮盖，未遮盖区域用HF蚀刻，然后用溶剂去除遮盖物。用志愿者的菌斑进行微生物挑战。将常规植入物（对照组）和原型植入模拟种植体周围环境中，该环境通过浸入生长培养基中的玻璃纤维套管实现。生长五天后，取样并用硝酸消化。通过电感耦合等离子体质谱法评估溶解的钛。
结果 成功制造出概念验证植入物原型。真空沉积可产生可重复的稳定钛涂层。使用原子力显微镜估计钛涂层的厚度。微生物挑战表明与商业钛植入物相比，新的植入物原型显示出腐蚀浸出的钛量减少。
结论 我们展示了一种新型牙科植入物设计的前进方向，即腐蚀诱导的电流被中断，导致溶解钛的量减少。
