Researchers from the RMIT University in Melbourne, Australia have successfully coated a 3D-printed titanium medical implant in fine synthetic diamonds. They used a special microwave heating chamber to do it.
The results of the experiment were published on March 13 in the ACS Applied Materials and Interfaces journal. The new diamond-coated titanium material could be used in the future for medical implants such as hip or knee replacements, Live Science reported.
The researchers explained that they used synthetic diamonds, not for aesthetic purposes but because the diamond-coated implants will likely be more compatible with the human body and less prone to infection compared to pure titanium implants.
Pure titanium implants are currently used commonly, but too often, it does not interact with the human body the way we need to, Kate Fox, a senior researcher at the RMIT University, said. To work around the problem, they used the diamond on 3D scaffolds to create a surface coating that sticks better to cells commonly found in animals.
The scientists made a fine diamond coating by using detonation nanodiamonds. These are extremely tiny synthetic diamond crystals that are usually created by a controlled explosion. It is just a few millionths of a centimeter long. Detonation nanodiamonds take only a few minutes to create in a laboratory and are relatively cheap compared to natural diamonds that can take billions of years to form in the mantle of the Earth.
But the RMIT scientists did not set off an explosion. Rather, they created the synthetic diamonds using a chemical vapor diamond plasma chamber, a machine, where the continuous blast of superhot microwaves heats methane and hydrogen gases up to 1,000 degrees Celsius. The heat turns it into a super-reactive plasma that is capable of forming diamond crystals on certain surfaces.
A technological first
The researchers then placed a 3D-printed piece of titanium scaffolding into the CVD chamber and turned on the microwaves. After they removed it from the chamber, the titanium was successfully coated in diamonds. Fox said it was a technological first.
But she said that the diamond-coated implants had yet to be tested in humans. However, she is confident that it will prove to be more compatible and less prone to infection than the pure titanium implants that are used today.
The integration between the living bone and the artificial implant is improved by the diamond, Fox explained. It reduces bacterial attachment over an extended period of time. She added the diamond coating not only leads to better biocompatibility for 3D-printed implants, it could also improve their wear and resistance because it is an exceptional biomaterial.
Various medical technologies had previously used diamonds such as artificial heart valves, drug-delivery systems, and prosthetics.
In 2013, scientists said they have discovered that tiny spherical diamonds could be used to promote bone growth and improve the durability of dental implants. Due to their size, the diamonds are invisible to the human eye. These could be tapped to battle forms of bone loss, including osteonecrosis which is a potentially debilitating disease wherein the bones break down because of reduced blood flow.
Nanodiamonds, the byproducts of conventional mining that are four to five nanometers in diameter, could be used as a delivery system for proteins in the mouth as an improved treatment for osteonecrosis, scientists from the UCLA and the NanoCarbon Research Institute in Japan found, Daily Mail reported.
The ailment affects the jaw and can prevent people from eating and speaking. People with the disease will suffer from a bone loss which occurs next to dental implants. It could lead to more painful and expensive procedures.
When doctors perform bone repair surgery which is usually expensive and time-consuming, they surgically insert a sponge to administer proteins that promote bone growth such as bone morphogenic protein, Dean Ho, a professor of oral biology and medicine at the UCLA School of Dentistry, said.
The researchers discovered that when they use nanodiamonds to deliver the proteins to the bone, the procedure could be more effective in administering the proteins as it quickly binds to the bone. The diamond’s unique surface permits the proteins to be delivered more slowly and allows the infected area to be treated for a longer period of time, Ho said.
Administration of the nanodiamond is non-invasive through injection or an oral rinse.
Studies in cells and animals have been conducted by scientists. The nanodiamonds are well tolerated which further increases their potential in dental and bone repair applications, initial studies showed, Laura Moore, a PhD student at Northwestern University who was involved in the study, said.
Ho pointed out that because the nanodiamonds are useful for delivering such a broad range of therapies, it has the potential to affect several other aspects of oral, maxillofacial, and orthopedic surgery and even regenerative medicine. In pre-clinical models, the researchers showed that nanodiamonds are also effective at treating multiple forms of cancer.
[researchpaper 리서치페이퍼= Vittorio Hernandez 기자]