To replace diseased bones or joints, orthopaedic implants have become necessary. Procedures such as hip, knee, and shoulder replacements have resulted from the evolution of implants.
For this purpose, metals such as titanium alloys and stainless steel are commonly used. Metal implants are biologically inert due to their smooth surface.
This can result in the formation of a non-adherent capsule that does not adhere to the bone. Daily wear and tear can cause aseptic loosening when this occurs, resulting in a gap between the bone and the implant over time.
To address this problem, hydroxyapatite (HA), a bio-active material, has been identified as an ideal coating for use in cement-free implant fixations. It is primarily used to coat hip, knee, and even dental implants. The bio-active HA coating promotes bone formation around the metallic implant.
“HA is referred to as a bio-active material due to its ability to form bonds with bone tissue. The HA coating in cement-less implant fixation promotes bone in-growth, which results in implant anchorage with bone,” explained Dr Jamuna Thevi Kalitheertha Thevar, a Senior Researcher at SIRIM’s Industrial Centre of Innovation in Biomedical.
The use of hydroxyapatite (HA) coating is well known for promoting bone integration between the bone and various medical implants. Calcium and phosphorus make up the majority of HA. This composition allows the HA coating on medical implants to connect structurally and functionally with human bone.
“As a result, it is ideal for patients with bone diseases or traumatic injuries, as well as the elderly,” she said.
To enable it to adhere to the metal implant, HA is used as a raw material in powder form for coating applications using an atmospheric plasma spray system at high temperatures.
Properties such as roughness, crystallinity, and thickness are evaluated according to ISO standard specifications to ensure that the coatings are suitable for medical applications (ISO 13779).
Taking the innovation further
Even though the HA coating is still in the research and development stage, local medical device manufacturers have expressed interest. SIRIM encountered a company looking for a service provider offering coating services during a recent technology audit programme.
“This has been a fantastic opportunity for SIRIM. We look forward to taking this innovation even further as it enters the clinical trial phase before being commercialised,” Dr Jamuna said.
She is confident the HA coating service will benefit the medical device industry, elevating Malaysia’s position as a regional leader in medical device manufacturing. Local medical implant manufacturers will add value to their products by producing finished products with the help of the HA coating service. Local dental implant manufacturers have taken notice of this coating service.
“This service will strengthen Malaysia’s capability to produce high-end finished medical products for the global market,” she stated.
There is a transition period between research and development and commercial production, according to Dr Jamuna.
“For starters, the company must be capable of producing large quantities on a large scale in an efficient manner. As a result, the coating properties are being improved per the manufacturer’s standard specifications. Meanwhile, it must improve production capability, achieve low production costs, and deliver coated implants of unrivalled quality.”
Furthermore, because the implants are medical devices, they must adhere to stringent medical standards. All of this can be time-consuming.
Dr Jamuna, on the other hand, sees room for expansion in this sector.
“In the northern region, we are surrounded by medical device manufacturers. Our market-driven research approach has created market solutions for potential users or buyers through value chain product innovation,” she explained.
Dr Jamuna was confident that SIRIM could provide innovative solutions to the country’s medical device industry because research and development are the organisation’s core strengths.
She used the current collaboration with a medical implant manufacturer as an example, noting that the manufacturer could not find a coating service provider locally before contacting SIRIM.
“However, to remain competitive on a global scale, we must continue to improve and grow in the medical sector. We must be able to continue to improve technological innovations in response to global trends.” — The Health