Ce-doped defective titanium oxide coating with antibacterial, antioxidant and anti-inflammatory properties for potential application of peri-implantitis treatment

• Published in: Rare metals 2025-01, Vol.44 (1), p.472-488
• Main Authors: Chen, Yun-Hao, Guan, Shi-Wei, Xing, Min, Yeung, Kelvin Wai-Kwok, Liu, Xuan-Yong, Qian, Wen-Hao, Yin, Jing-Bo, Qiu, Jia-Jun
• Format: Article
• Language: English
• Subjects: Antiinfectives and antibacterials; Antioxidants; Cell adhesion; Cerium; E coli; Genes; Heat treatment; Hydrogen peroxide; Near infrared radiation; Oxidation; Oxide coatings; Radiation damage; Soft tissues; Sulfonic acid; Thermal reduction; Titanium; Titanium oxides
• ISSN: 1001-0521; 1867-7185
• DOI: 10.1007/s12598-024-02935-y

Implant-related infections and tissue inflammation are the main factors for peri-implantitis. Lack of antibacterial activity and poor soft tissue sealing property increase the occurrence probability of peri-implantitis. To prevent and treat peri-implantitis, cerium-doped defective titanium oxide coatings are prepared on medical titanium surfaces by plasma electrolytic oxidation and thermal reduction treatment. In the darkness, Ce-doped defective titanium oxide coatings with micro-porous structure surface can inhibit the bacteria adhesion to some extent with antibacterial rates of 38.0% against S. aureus and 65.0% against E. coli. Under near infrared (NIR) irradiation, Ce-doped defective titanium oxide coatings show good photothermal antibacterial activity with antibacterial rates of 99.9% against S. aureus and 99.9% against E. coli. Moreover, with the increasing content of Ce-doping, the coatings exhibit higher capacity to scavenge hydrogen peroxide (H2O2) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS·+). The coatings with enhanced antioxidant effect can protect human gingival fibroblasts from oxidative stress damage by eliminating reactive oxygen species and promoting initial cell adhesion. Besides, Ce-doped coatings can regulate the immune microenvironment by up-regulating the expression of anti-inflammatory genes and down-regulating the pro-inflammatory genes. In vivo animal experiments further confirm the good antibacterial activity of Ce-doped defective titanium oxide coatings under NIR irradiation and good biosafety. This work provides a novel surface modification strategy for implant abutment, which shows good application prospects for preventing and treating peri-implantitis.