Ultrashort Pulsed Laser Surface Patterning of Titanium to Improve Osseointegration of Dental Implants

Abstract

Ultrashort pulsed direct laser interference patterning (DLIP) is used to generate hierarchical line‐like patterns on titanium surfaces to control cell adhesion and spreading on dental implants, thereby improving osseointegration. The DLIP structures have spatial periods of 3, 5, 10, and 17 μm. They are produced using a laser source with a pulse duration of 10 ps and cumulated energy densities between 0.1 and 78.9 J cm−2. Laser‐induced periodic surface structures (LIPSS) and submicron features are obtained on the treated samples. The DLIP treatment leads to the development of a thick titanium oxide layer, which is imaged and quantified using time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS). Several days (30–56) after the laser treatment, specimens with larger spatial periods are hydrophilic, whereas samples with spatial periods of 3 μm are hydrophobic. Seeded human osteoblasts on the laser‐structured samples show 2.5 times higher cell numbers after 7 days in vitro culture compared with osteoblasts on a grit‐blasted and etched reference sample. Finally, cell adhesion to a structured 3D dental implant is demonstrated.

Quo Vadis LIPSS?—Recent and Future Trends on Laser-Induced Periodic Surface Structures

“…Depth-resolved surface analytical studies on LIPSS based on Auger electron microscopy (AEM) [ 9 ], time-of-flight secondary ion mass spectrometry (TOF-SIMS) [ 40 ], and glow-discharge optical emission spectroscopy (GD-OES) [ 41 ] indicate a graded oxidized surface layer of several hundreds of nanometer thickness. Such nanostructured oxide layers may, however, exhibit beneficial tribological effects, particularly in combination with “anti-wear” additives, such as zinc-dialkyl-dithiophosphate (ZDDP), contained in lubricants, such as commercial engine oil [ 41 , 42 , 43 ].…”

Repellent rings at titanium cylinders against overgrowth by fibroblasts

“…Controlled cell-adhesion on titanium (Ti) surfaces due to femtosecond-laser induced micro-and nanostructures have been investigated by several groups in the last years [1][2][3]. This interest is triggered by the fact that Ti and Tialloys are often used materials for medical implants, for instance in dentistry, orthopedics, and for cardio-vascular applications.…”

Chemical effects during the formation of various types of femtosecond laser-generated surface structures on titanium alloy

“…Although fs-laser processing experiments are usually performed in air allowing oxidation reactions of the irradiated material with the ambient and reactive air environment, so far only little research has been devoted to chemical effects accompanying the formation of LIPSS [36][37][38][39]. Particularly for the highly reactive material titanium, such effects were already shown to be relevant for the processing of LIPSS [30,[40][41][42][43]. For simplicity, most of the experimental studies rely on EDX.…”