New coating method allows stronger adhesion of dental implant
SEOUL, South Korea: The history of dental implantology dates back to ancient times, yet researchers are still trying solve a number of issues, such as failed osseointegration and inflammation. Researchers from the Korea Institute of Science and Technology (KIST) Center for Biomaterials have now developed a novel method of producing a ceramic artificial bone coating for implants. This method is distinguished by a shorter production process and increased adhesion of the coating.
Owing to enhanced biocompatibility and osseointegration, hydroxyapatite coatings are often applied to biomedical devices that are implanted directly on bone. However, they require a synthesis process in order to manufacture the artificial bone material and a separate coating process, which is time-consuming. In addition, the binding between the substrate and the artificial bone coating layer tends to be weak, resulting in damage or even failure.
“Hydroxyapatite coating is already widely used. However, when it peels off, it can be seen that the coating layer is ineffectual,” said Dr Hojeong Jeon, principal research scientist at KIST, in an interview with Dental Tribune International.
To mitigate these issues, the research team developed a method of inducing artificial bone coating in only 1 hour using a single process, which does not require separate synthesis of the raw material for artificial bone coating. They positioned the material to be coated in a solution containing calcium and phosphorous and irradiated it with a laser. The temperature was increased locally at the laser’s target site, causing a reaction of calcium and phosphorus to produce ceramic artificial bone (hydroxyapatite) and to form a coating layer.
Compared with conventional coating methods, the new technique creates a coating layer with a stronger binding power. “The coating method we developed increases the adhesion strength. We expect the laser-induced coating to have at least a three or four times higher adhesion strength than the coating layer formed by the thermal plasma spray method,” said Jeon. In addition, the coating may be applied not only to metal surfaces but also to the surfaces of polymer materials, which has not been possible with conventional processes so far.
According to Jeon, KIST is currently working with a South Korean orthopaedic company to optimise the technology for application to products. It is expected to be available on the market in about three years. “The biggest advantage of this new method is decreasing time and cost for the hydroxyapatite coating process while increasing the coating adhesion strength,” he concluded.
The study, titled “Robust hydroxyapatite coating by laser‐induced hydrothermal synthesis”, was published online on 15 September 2020 in Advanced Functional Materials, ahead of inclusion in an issue.