Research shows how to improve the bond between implants and bone

Research carried out recently at the Canadian Light Source (CLS) in Saskatoon has revealed promising information about how to build a better dental implant, one that integrates more readily with bone to reduce the risk of failure.

“There are millions of dental and orthopedic implants placed every year in North America and a certain number of them always fail, even in healthy people with healthy bone,” said Kathryn Grandfield, assistant professor in the Department of Materials Science and Engineering at McMaster University in Hamilton.

A dental implant restores function after a tooth is lost or removed. It is usually a screw shaped implant that is placed in the jaw bone and acts as the tooth roots, while an artificial tooth is placed on top. The implant portion is the artificial root that holds an artificial tooth in place.

Grandfield led a study that showed altering the surface of a titanium implant improved its connection to the surrounding bone. It is a finding that may well be applicable to other kinds of metal implants, including engineered knees and hips, and even plates used to secure bone fractures.

About three million people in North America receive dental implants annually. While the failure rate is only one to two percent, “one or two percent of three million is a lot,” she said. Orthopedic implants fail up to five per cent of the time within the first 10 years; the expected life of these devices is about 20 to 25 years, she added.

“What we’re trying to discover is why they fail, and why the implants that are successful work. Our goal is to understand the bone-implant interface in order to improve the design of implants.”

>Read more on the Canadian Light Source website

Google Maps for the cerebellum

A team of researchers from Göttingen has successfully applied a special variant of X-ray imaging to brain tissue. With the combination of high-resolution measurements at DESY’s X-ray light source PETRA III and data from a laboratory X-ray source, Tim Salditt’s group from the Institute of X-ray Physics at the Georg August University of Göttingen was able to visualize about 1.8 million nerve cells in the cerebellar cortex. The researchers describe the investigations with the so-called phase contrast tomography in the Proceedings of the National Academy of Sciences (PNAS).
The human cerebellum contains about 80 percent of all nerve cells in 10 percent of the brain volume – one cubic millimeter can therefore contain more than one million nerve cells. These process signals that mainly control learned and unconscious movement sequences. However, their exact positions and neighbourhood relationships are largely unknown. “Tomography in the so-called phase contrast mode and subsequent automated image processing enables the cells to be located and displayed in their exact position,” explains Mareike Töpperwien from the Institute of X-ray Physics at the University of Göttingen, lead author of the publication.

>Read more on the PETRA III at DESY website

Image: Result of the phase contrast X-ray tomography at DESY’s X-ray source PETRA III.
Credit: Töpperwien et al., Universität Göttingen

Dark-field X-ray microscopy provides surprising insight on ferroelectrics

Thanks to the unique capabilities of in-situ dark-field X-ray microscopy, scientists have now been able to see the complex structures hidden deep inside ferroelectric materials. The results, published today in Nature Materials, contradict previous studies in which only the surface was studied. This revolutionary new technique will be the main feature of a new beamline for the new EBS machine currently being built at the ESRF.

“Until now we could only see the surface of the material; dark-field x-ray microscopy is like creating a window to its interior”, explains Hugh Simons, assistant professor at the Technical University of Denmark and corresponding author of the study. “It provides incredible contrast for even the subtlest structures inside these materials, giving us a much clearer picture of how they work”, he adds.

Simons, together with the team of ID06 – the beamline where the technique is being developed – studied the ferroelectric material BaTiO3, which is used every day in cars, computers and mobile phones. By imaging their internal structure at the same time as they applied an electric field on it, they could see how these internal structures behave and change dynamically.

>Read more on the European Synchrotron (ESRF) website

Image: (extract) Crosssectional dark-field x-ray microscopy maps of the embedded BaTiO3 grain. (…) the reconstructed strain map reveals the structural relationship between domain clusters. Full picture here.
Credit: H. Simons.

The early bird got to fly: Archaeopteryx was an active flyer

Was Archaeopteryx capable of flying, and if so, how?

The question of whether the Late Jurassic dino-bird Archaeopteryx was an elaborately feathered ground dweller, a glider, or an active flyer has fascinated palaeontologists for decades. Valuable new information obtained with state-of-the-art synchrotron microtomography at the ESRF, the European Synchrotron (Grenoble, France), allowed an international team of scientists to answer this question in Nature Communications. The wing bones of Archaeopteryx were shaped for incidental active flight, but not for the advanced style of flying mastered by today’s birds.

Was Archaeopteryx capable of flying, and if so, how? Although it is common knowledge that modern-day birds descended from extinct dinosaurs, many questions on their early evolution and the development of avian flight remain unanswered. Traditional research methods have thus far been unable to answer the question whether Archaeopteryx flew or not. Using synchrotron microtomography at the ESRF’s beamline ID19 to probe inside Archaeopteryx fossils, an international team of scientists from the ESRF, Palacký University, Czech Republic, CNRS and Sorbonne University, France, Uppsala University, Sweden, and Bürgermeister-Müller-Museum Solnhofen, Germany, shed new light on this earliest of birds.

>Read more on the European Synchrotron website

Image: The Munich specimen of the transitional bird Archaeopteryx. It preserves a partial skull (top left), shoulder girdle and both wings slightly raised up (most left to center left), the ribcage (center), and the pelvic girdle and both legs in a “cycling” posture (right); all connected by the vertebral column from the neck (top left, under the skull) to the tip of the tail (most right). Imprints of its wing feathers are visible radiating from below the shoulder and vague imprints of the tail plumage can be recognised extending from the tip of the tail.
Credits: ESRF/Pascal Goetgheluck

Natalie Larson awarded

She received the Neville B. Smith Student Poster Prize

Natalie Larson, a current ALS doctoral fellow from UC Santa Barbara, won the first prize Neville B. Smith Student Poster Award at the 2017 ALS User Meeting. Larson’s winning poster—”In-situ x-ray computed tomography of defect evolution during polymer impregnation and pyrolysis processing of ceramic matrix composites”—featured the first two big in situ experiments she performed at Beamline 8.3.2.

Larson has been an ALS user since 2014 and became a doctoral fellow in 2016. She’ll continue at the ALS for about another year through a National Science Foundation fellowship that will see her through the end of her PhD. The primary focus of her work is developing high-temperature ceramic matrix composites (CMCs) for more efficient jet engines. Larson works with Beamline Scientists Dula Parkinson and Alastair MacDowell and Project Scientist Harold Barnard on developing experiments for in situ x-ray computed tomography experiments to observe 3D real-time defect formation in CMCs.