Spiked Titanium Nanostructures That Inhibit Anaerobic Dental Pathogens

Abstract

Peri-implantitis is a devastating oral disease that has given rise to a demand for improved implantable dental biomaterials that can integrate well into the supporting bone as well as resist bacterial colonization. Recent research has demonstrated that nanostructured titanium may be well positioned to meet this demand. An abundance of literature has established the in vitro efficacy of nanostructured titanium against bacteria cultured aerobically, but its efficacy against anaerobic bacteria relevant to dental infections remains unknown. In the present study, we engineered sharp, spikelike nanostructures on commercially pure titanium surfaces using hydrothermal etching and challenged them with three clinically relevant, anaerobic dental pathogens: Streptococcus mutans, Fusobacterium nucleatum, and Porphyromonas gingivalis. Our results demonstrated that titanium nanostructures bearing sharp protrusions can be effective at eliminating bacteria in anaerobic conditions, in both single-species (up to ∼94% cell death) and dual-species (up to ∼70% cell death) models. Furthermore, surface modification greatly enhanced the efficacy of azithromycin treatment against anaerobic dental pathogens, compared to a control titanium surface. At 2× MIC (minimum inhibitory concentration), azithromycin eliminated 99.4 ± 0.3% of S. mutans on the nanostructured surface within 10 days, while only 26% of the bacteria were killed on the control surface. A similar result was observed for P. gingivalis. The data presented here serve as a promising foundation of knowledge on which to build a greater understanding of how nanostructured biomaterials can be effective in anaerobic environments such as that found in the oral cavity.

Dual Species Bacterial Challenge of a Biomimetic Nanostructured Surface

“…The AR‐Ti samples were treated with a hydrothermal etching process previously described. [ 19b,21 ] Briefly, samples were immersed in 1 m KOH, sealed in a cylindrical steel vessel, and heated to 150 °C for 5 h, rinsed in ultrapure water, and then annealed for 5 h.…”

Fabrication of a TiO2@Cu Core–Shell Nanorod Array as Coating for Titanium Substrate with Mechanical and Chemical Dual Antibacterial Property

“…The antibacterial mechanism of TiO 2 @ Cu/Ti included the following three points: (a) While bacteria attached to the TiO 2 nanorod array on the sample surface, the membrane of bacterial cells became deformed and stretched under the mechanical force, which caused the cell membrane to lyse in overstretching, resulting in the bacterial death. 48 (b) During the contact of the Cu shell with the membrane of bacterial cell, the fluidity and permeability of cell membrane were altered, causing the leakage of the cytoplasmic content. 49 (c) Cu 2+ released from the surface of the sample could enter into the bacterial cell body, which directly led to the dysfunction of the related protein and nucleic acid, thereby affecting the bacterial activity.…”

Early Antimicrobial Evaluation of Nanostructured Surfaces Based on Bacterial Biological Properties

“…6,7 Considering the increasing antibiotic resistance of bacteria, physical antibacterial surfaces, especially the ones with nanoscaled structures, have drawn extensive attention during the past decade. 8 However, many studies, focusing on the physical antimicrobial behavior of biomaterials, usually show contradictory results, even on the substrates with the same surface treatment. 9,10 For example, the physiologically young bacteria adhere in large numbers on the nanostructured surfaces, while the attachment of physiologically old bacteria on the nanostructured surfaces is inhibited.…”