中国国际医疗器械设计与制造技术展览会(Medtec China)2021

Dedicated to design & manufacturing for medical device

August 31-September 2 2022 | SWEECC H1&H2

Material Trends: The Impact of New Medtech Innovation

2022-03-14

The betrayal was gradual at first.

It began with the triple-whammy rapid heartbeat, chest tightness, and dizziness—symptoms vague enough to portend almost any kind of malady, serious or not.

Nadia Dara Diskavets chose the “or not” option, chalking up her wonky corporeal state to panic attacks. But Diskavets quickly realized her mistake when her body started double- crossing her more often and in more mysterious ways: fatigue so extreme she could hardly move; joint pain so harrowing she could scarcely sit; brain fog so thick she could barely think; and digestive dysfunction so severe she could hardly eat.

New symptoms arose regularly, exacerbating Diskavets’s medical mystery. She experienced full-body tingling, skin rashes, tinnitus (ringing in the ears), hair loss, allergies, premature ovarian failure, mood swings, and slow-healing wounds. One day, the top of her stomach began pulsating.

“I felt like I was constantly jet-lagged, walking around with a pillow over my ears and a foggy glass jar over my head,” the New York City-based photographer recounted in a personal essay on mindbodygreen.com. “I had blurry vision and struggled to stay alert or to comprehend what was going on around me. I couldn’t remember anything. More new symptoms were showing up almost every week: recurring infections, muscle weakness, headaches, mood swings...I’m sure I’m forgetting a few others, but those were just some of the ailments I dealt with on a daily basis while doctors insisted that because all my bloodwork was normal, all of this ‘must be in your head.’”

The doctors were wrong, of course. Diskavets’s unusual maladies weren’t limited to her head—they were coursing throughout her body, and at an alarming rate. A diagnosis of heavy metal toxicity (high levels of mercury, lead, arsenic, thallium), IBS, adrenal fatigue, and small intestinal bacterial growth yielded more questions than answers. Diskavets was particularly perplexed about the source of all those heavy metals.

The metals’ origin remained an enigma until Diskavets read a friend’s Facebook post about breast implant illness and immediately recognized the symptoms. Upon joining a breast implant illness Facebook group and reading countless posts, Diskavets realized her silicone implants were the source of all her medical misery.

“While reading all of their stories, I kept remembering how I had been told that implants were harmless and silicone was inert in our bodies,” Diskavets wrote in her essay. “The symptoms of breast implant illness are sneaky and disguise themselves as other diseases. Apparently, silicone is not inert as some doctors and implant companies have claimed. It sweats and bleeds from the insertion.”

The (potential) health impacts of silicone breast implants has been widely studied and debated in recent years amid reports of rare cancers and symptoms like fatigue, memory loss, rashes, digestive issues, allergies, and joint pain. Some studies have linked silicone breast implants to various rare diseases, conditions, and autoimmune disorders, while others failed to find evidence of such a relationship. As a September 2021 article in The Journal of the American Medical Association noted, “...many women with breast implants experience sometimes debilitating symptoms, and the level of evidence to support the treatment of these women leaves room for improvement.”

After conducting her own research, Diskavets decided to have her silicone breast implants removed (they had been inside her body for eight years at the time of their departure). Two of her “most persistent” symptoms disappeared the day after the explant surgery, while her debilitating joint pain and anxiety dissipated within weeks. Most other symptoms resolved in the first four months following surgery.

Diskavets’s ordeal is among the thousands that have recently helped inflame the decades- long controversy surrounding silicone breast implants, first introduced in the 1960s. The U.S. Food and Drug Administration (FDA) and other regulatory agencies worldwide have long wrestled with ways to better scrutinize these devices and improve patient safety. After years of study and debate, the FDA last fall issued new, more stringent rules for breast implant manufacturers, including Johnson & Johnson and AbbVie’s Allergan, which recalled its textured Biocell and Natrelle implants in 2019 upon the agency’s request.

Under the new rules, saline- and silicone gel-filled breast implants can only be sold to health providers that review potential surgical risks with patients using an FDA-mandated checklist. That list must advise patients of the potential risks/side effects of breast implant surgery (including its link to an immune system cancer) and also identify women who might have a greater chance of falling ill after the procedure (breast cancer patients and those undergoing chemotherapy or radiation treatments).

The FDA also is requiring breast implant manufacturers to include a boxed warning on the product’s label that discloses the materials used in production, and updated MRI screening recommendations for spotting “silent ruptures” of silicone gel-filled implants.

“This is information that every patient contemplating breast implants should know,” Binita Ashar, director of the Office of Surgical and Infection Control Devices in the FDA’s Center for Devices and Radiological Health (CDRH), said upon issuing the new rules last October. “We want patients to make informed decisions about whether or not breast implants are right for them.”

Those decisions, however, are virtually impossible without an “ingredient list.”

Mindful that such a list could help improve overall medical device safety and efficacy, the CDRH currently is working to expand its materials information mandate beyond breast implants. Last spring, the agency solicited feedback on a medical device content labeling change that would require more specific material information on products with long-term exposure to human tissue (i.e., metal-on-metal hips, female sterilization devices).

Specifically, the CDRH is proposing that medical devices designed for long-term use list specific material composition on their labels, and provide patient counseling recommendations. In addition, CDRH is considering requiring patient labeling for long-term products without labels; this new marking could include—among other particulars—a basic description of the device and an easily-understandable list of patient-contacting materials.

Besides its proposed labeling changes, the CDRH is partnering with ECRI to promote the use of safer medtech materials. Through an ongoing, multi-year endeavor, ECRI is developing safety summaries for materials commonly used in implantable medical devices, and assessing the possible long-term effects of those substances.

“These evaluations are part of the FDA’s broader initiative to improve the safety of medical devices through the use of safer materials and preventing patients at risk for an adverse response to select materials from receiving devices that contain them,” Ed Margerrison, Ph.D., director of the CDRH’s Office of Science and Engineering Laboratories, said in an online statement announcing the ECRI partnership. “The FDA believes this information will be a useful tool for innovators in selecting materials and components for future medical products, resulting in patients and doctors having better access to more effective and safer medical devices.”

ECRI’s material data could prove extremely useful as demand grows for medical wearables and miniaturized devices and diagnostics. The global medical wearables market is set to flourish over the next five years, expanding 26.4 percent annually to reach $195.57 billion in value by 2027, according to Fortune Business Insights Ltd. data. The market research and consulting firm attributes the sector’s growth to society’s obsession with fitness and well-being, and the increasing prevalence of chronic conditions (diabetes, heart disease) among an aging world population.

Medical wearables use multimedia, wireless communication, and sensor technology to monitor and collect physiological data. Since they measure biological activity through the skin, most wearables usually are designed to be flexible, stretchable, biocompatible, and comfortable. Achieving such qualitative harmony, however, is difficult without solid knowledge of the human epidermus.

The skin is the body’s largest organ, boasting an area approximately 20 square feet. Comprised of three layers—epidermis, dermis, subcutis—skin acts as a protective barrier, storage bunker (fats and water), and temperature regulator. It regularly changes shape, moisture con- tent, and elasticity, and constantly sheds dead cells (30,000-40,000 a minute).

The skin’s three layers vary in thickness, with the heaviest on the palms (hands) and bottoms of feet, and the thinnest on the eyelids. Accordingly, medical wearables must be designed using adhesives and materials that account for such variability.

“Wearable technology is a big trend right now, and any growth in [medical] wearables raises the bar in material choices,” noted Aditi Subramanian, strategic business unit manager, Healthcare at FLEXcon Company Inc., a global developer of coated and laminated films and adhesives. “As advancements are made in making devices smaller or acquiring a signal from non-traditional areas of the body, the challenge becomes finding the proper materials to attach those devices to the body and enable them to stay on long enough to do their job. With the FLEXcon dermaFLEX line of skin-friendly adhesives, our goal has been to develop adhesives and substrates that take into account all skin types—that don’t leave people with adverse skin reactions while also performing for the intended period of time.”

FLEXcon’s dermaFLEX lineup leverages the properties of flexible substrates such as foam, non-woven polyester, urethanes, and nylon-reinforced to produce skin-friendly, biocompatible adhesives that can be used in medical tapes, wearables, diagnostic applications, and surgical drapes.

German polymer supplier Covestro AG used some of those same materials to develop a biocompatible medical monitor patch. Engineered in conjunction with design consultancy Entwurfreich GmbH, the patch combines breathable thermoplastic polyurethan (TPU) films, skin-compatible foam, and adhesives. Electronics printed on the TPU film and embedded in a thermoformable polyurethane foam are covered in a second film layer for improved comfort, according to Covestro. The patch attaches to the body via a polyurethane adhesive that adheres firmly to skin but is easily (and painlessly) removed.

“The medical adhesive is crucial for multilayer laminated materials, and adhesive material suppliers are in touch with the market’s need for conformability, biocompatibility, and in some cases, transparency. We work closely with OEMs to help them determine the optimal way to laminate different materials together,” explained Ralph Tricomi, director, market development at Web Industries Inc., a Marlborough, Mass.-based contract manufacturing firm offering precision converting and outsourced manufacturing services. “To help customers make multilayer products incorporating electronics, we have equipment to print on a substrate, do the multilayer lamination and then die cutting, island placement, or other converting processes. Advanced adhesives often are the method of choice to bond these layers together.”

“There is a convergence of chemistry, electronics, and medical devices in the development of solutions to improve quality of life through early disease detection and diagnosis of maladies. We are seeing greater integration of electrical circuits and multielectrode arrays into flexible, medical-grade materials,” he continued. “These materials then are used in testing devices and medical wearables with increasingly sophisticated detection capabilities and digital connectivity.”

Material advancements are likely to make those wearables and testing devices even more sophisticated in the coming years as researchers strive to improve both the power and performance of medical sensors. Japanese engineers, for example, have developed an ultra-thin, lightweight “e-skin” sensor designed to detect and monitor chronic disease.

The sensor is made from a flexible material—polyvinyl alcohol—and contains a layer of gold. It uses water to stick to skin, and can be worn for up to seven days to detect heartbeats and electrical impulses from muscle movement. “E-skin is the next generation of wearables,” Takao Someya, Ph.D., e-skin inventor and professor at the University of Tokyo’s Department of Electrical and Electronic Engineering, told CNN Business last spring. “Today’s mainstream wearables are in the form of smart watches and glasses, which are bulky. In contrast, e-skin is thin, lightweight, stretchable, and durable.”

So is the artificial skin created by engineers at the University of Toronto.

AISkin, or artificial ionic skin, is a transparent self-powering adhesive sensor that can sense when it is being touched, bent, heated, or otherwise manipulated. The sensor is made of two oppositely-charged hydrogel sheets stacked on top of each other; the positively- and negatively-charged ions in these sheets move across a junction (“sensing junction”) when subjected to humidity, mechanical strain, or temperature changes. Researchers say this movement can be measured as electrical signals.

Like Someya’s e-skin, the Canadian team’s sensor easily adheres to skin without breaking or prematurely peeling off, and it is eight times more stretchable than the human epidermis. Researchers currently are working to enhance AISkin by adding bio-sensing capabilities for measuring biomolecules in bodily fluids, and shrinking the sensors’ size.

The latter augmentation is not without its challenges, though. Miniaturizing medical sensors and other devices for internal or external use requires a careful balance of appropriate design, manufacturing technique, and materials. Moisture, heat, and movement impact the design and composition of wearable sensors. Flexibility, for instance, can reduce sensor errors caused by movement, while graphene and carbon fibers provide the biocompatibility and elasticity sensors need for adhering to skin.

“Both materials and manufacturing processes are key in the decision of the correct materials to be used. We have materials that are self-lubricating thermoplastics that can be manufactured in different shapes and eliminate oil or grease requirements,” noted Charles Deleuze, business manager for Life Science, Omniseal Solutions (a St. Gobain business). “How the materials are manufactured and depending upon the environment in some instances, makes the decision on material choice [in medical device miniaturization]. It also makes a difference on the space constraints for material and product design. Some of the environment needs include wear and friction for duration of the product use, fluid or chemical resistance, amount of pressure, and mechanical operation of the application. Miniaturization and longer life/use are the two primary factors driving innovations in medical device materials science.”

But they’re not the only factors. Additive manufacturing and minimally invasive surgeries also are driving innovation in medtech materials, producing antibacterial implants, precise tissue scaffold constructs, and lighter-weight components.

Last summer, additive manufacturing solution provider Roboze debuted a 3D printer capable of producing lighter, higher-quality parts made of polyether ether ketone (PEEK), carbon PEEK, and ULTEM AM 9085F. Around the same time, German specialty chemical firm Evonik developed a new 3D printable PEEK biomaterial—VESTAKEEP Care M40 3DF—featuring biocompatibility, excellent temperature and chemical resistance, high strength, easy handling, and body contact capabilities for up to 30 days.

Premium specialty alloys developer and distributor Carpenter Technology offers several high-performance alloys for the medical device industry in wrought and powder form along with the capability to produce 3D printed parts at its Emerging Technology Centre. For additive manufacturing, Carpenter has developed enhanced Ti64ELI Grade 23+ powder along with next-generation material systems including nitinol alloys and a nickel- and cobalt-free austenitic stainless alloy called Biodur 108. The 3D printed nitinol products exhibit superelasticity and shape memory, while Biodur 108 boasts superior tensile and fatigue strength suitable for patients with metal allergy concerns, according to the Philadelphia-based firm.

“Improving patient outcomes is the focus of all innovation in medical devices and the availability of raw materials to enable [their] support and development is critical,” declared Gaurav Lalwani, global medical applications engineering lead for Carpenter Technology. “Additive manufacturing provides accessibility to novel implant designs that can provide design features not possible using traditional manufacturing such as the creation of porous implants for enhanced osseointegration and patient-specific implants along with production of complex device designs that are either not possible or too expensive to produce using subtractive manufacturing.”

“It has been widely recognized that 3D printing Nitinol—a key medical alloy—with effective translation of shape memory and super elasticity properties is a challenge,” Lalwani added. “3D printed Nitinol has limited shape memory and superelasticity compared to the wrought materials. These material properties are extremely sensitive to subtle changes in alloy chemistry. At Carpenter Technology, we have been successful in producing high-quality inert gas-atomized Nitinol powders and have demonstrated effective translation of these properties for medical applications.”

Carpenter Technology is currently working to develop an improved stainless-steel product specifically for minimally invasive and robotic surgical applications. Its intended target—a precipitation hardening martensitic material (17-4PH) with minimum residual stress—would allow for minimal deflection during machining and engender advanced, hands-off manufacturing of complex and thin-wall geometries.

Such manufacturing prowess will be valuable in the near future as demand grows for surgical techniques and technologies that reduce pain and body trauma. Both minimally invasive and robotic-assisted surgeries are projected to gain significant market share this decade, with the global MI sector forecast to climb 4.7 percent annually through 2030, and the robotic-assisted procedure market presaged to soar 17.6 percent annually through 2028, industry data indicates.

“Surgical robotics automation needs may require more self-lubricious and stronger wear materials,” Deleuze said in portending the medical materials market’s evolution over the next five years. “Polymer and composite-based products may provide improved maneuverability over incumbent materials to reach hard-to-access areas of the anatomy during surgery. Engineered polymers will reduce the cost of robotic systems through design and architecture changes, and there may be a movement from metal products to engineered plastics for lightweight and smaller devices, as already seen in smaller motors.”

Indeed, smaller and lighter weight devices will likely figure prominently in medtech’s future, given the industry’s proclivity for miniaturized products and healthcare’s overall digitization. But this evolution is equally as liable to beget some difficult conversations about medical de-vice sustainability (or lack thereof).

Environmental sustainability has increasingly infiltrated social platforms and corporate agendas in recent years amid the world’s rising temperatures and polluted expanses. The global pandemic has only exacerbated the problem, adding roughly 3.4 billion discarded single-use facemasks and face shields daily to the planet’s mounting trash pile.

The medtech industry is a significant contributor to the heap: Roughly 90 percent of medical device waste consists of single-use disposable products or components, reports indicate. Efforts to reduce the efflux of waste is complicated by the need to produce safe products that effectively treat disease.

Nevertheless, device manufacturers becoming increasingly mindful of sustainability as they realize the benefits that accompany environmental stewardship—namely, cost savings, improved brand (and social image), investor appeal, and competitive edge.

“Industry OEMs are requiring Life Cycle Analysis (LCA) reports to win project bids. Why? Responsibility,” stated Mark Denning, medical market business manager for sustainable thermoplastic material solutions provider SEKISUI KYDEX. “Whether it’s the material or the process, medical device manufacturers are considering their devices’ impact on the earth. The design and engineering teams are taking into consideration what the impact of the device will be after its life cycle is complete. The challenge is in understanding if sustainability is only about the ability to recycle materials or if it includes the impact of the manufacturing process of the materials from the beginning. This is where material education will be key over the next few years to get more sustainable solutions in use on medical devices.”

SEKISUI KYDEX has already mastered that challenge. Its KYDEX Thermoplastics line—made from domestically sourced PVC/acrylic technology—has a base chemistry of salt and natural gas. The material is robust, impact resistant, unaffected by harsh disinfectants, and perhaps most importantly, is completely recyclable.

“Scrap material is either recycled directly back into the process during manufacturing or processed through our third-party in-house recycler, Ultra-Poly, for end-of-life solutions,” Denning said. “Recycled medical device housings can become park benches, art installations, dunnage trays, or more.”

No such luck for all those disposable face masks. They’ll mostly end up in landfills.

Yet the powder blue cover up’s existence isn’t all for naught. Besides serving as a wakeup call for medical device sustainability, the N95 knock-offs also taught materials vendors some valuable supply chain management lessons.

With raw materials in short supply, companies worked more closely with their partners to better manage annual demand forecasts, improve their understanding of customers’ needs, and qualify and multi-source other substances for existing products. Carpenter Technology, for example, implemented a strategically staged work-in-process materials program to help stabilize lead times, stocked regional warehouses (for just-in-time delivery requests), and forged more contractual agreements with directed buy programs.

Apple Rubber noticed companies abandoning their just-in-time inventory strategies in favor of second sourcing solutions.

“The just-in-time supply is being thrown out the window. Higher safety stock levels are needed to assure production since consistent material shipments might not happen with COVID-19 supply challenges,” Apple Rubber Materials Manager John Tranquilli said. “This is an opportunity for the medical [device] industry to develop better procedures on second sourcing material. For example, only one compound will be tested for application. So when supply disruptions like COVID-19 happen, material changes are not allowed, so production is shut down. Approving multiple materials in the final design will help assure production during supply disruptions. Or, companies need to have efficient procedures to support new material during supply shutdowns.”

Communication was key for Shelton, Conn.-based Modern Plastics, a distributor of high-performance stock shape and medical-grade plastics. “We communicate regularly with our customers and we provide recommended buying strategies to avoid any disruptions in the supply chain,” President Bing Carbone told Medical Product Outsourcing. “A big factor is the communication process between our company and our customers, seeking the best possible forecasting information possible so we can appropriately modify our Connecticut-based inventory levels to meet their requirements. 2022 will certainly have many challenges on very abnormal lead times and resin shortages but Modern Plastics has enormously increased inventory levels based on historical purchase information we have and anticipating the needs of our customers.”

Sounds like a lesson well-learned.

Article source: Medical Product Sourcing