By Sean Fenske, Editor-in-Chief
 
Durable, hard metals are the predominant material used for orthopedic implants. In recent years, however, device makers have been seeking alternatives that provide a more holistic approach to integrating the implant with the body. As such, they have become interested in the use of bioresorbable materials to replace the more traditional metals.
 
Bioresorbable materials used in the orthopedic space could be polymers or metals, but all help to return the body to its natural form. While the applications for their use are limited, it’s possible they may grow as material science continues to evolve.
 
With this in mind, it’s important to partner with a company who is at the forefront of these materials and constantly improving upon the processes that leverage them. Raghu Vadlamudi, chief research and technology director for Donatelle, is one such person. He took time to speak with Orthopedic Design & Technology about the use of these materials within the orthopedic space, important considerations to keep in mind, and the advantages they present.
 
Sean Fenske: What are bioresorbable molded devices? Does the body actually absorb the device?
 
Raghu Vadlamudi: Bioresorbable devices are manufactured using natural or synthetic polymers and metals that can be broken down by hydrolysis. Once they are implanted, the material will be broken down and absorbed by the body. The device does not need to be removed like devices manufactured using stainless steel or titanium. Examples of bioresorbable polymers are polylactide, polyglycolide, and their copolymers. Metals such as magnesium are also being used to manufacture bioresorbable devices.
 
Fenske: How is bioresorbable molding being used for orthopedic devices and implants? What are the advantages?
 
Vadlamudi: Orthopedic scaffoldings and screws are currently being molded with bioresorbable materials. Molding of these devices will result in material savings and faster production rates in comparison to machining processes. In turn, this reduces overall cost of manufacturing in addition to clinical benefits with functional improvement.
 
Fenske: Are there important factors orthopedic device manufacturers need to keep in mind when considering the use of bioresorbable molded devices?
 
Vadlamudi: Yes. Bioresorbable device makers need to take price and availability into account, and they must possess knowledge in handling and processing the material. It can become expensive if the device manufacturer does not have the expertise in-house or access to a competent supplier. Processing bioresorbable materials demands strict adherence to good manufacturing practices within a suitable environment. Consistency in processing is critical.
 
Fenske: Are there material considerations the device manufacturer needs to keep at the top of mind before moving forward with a design?
 
Vadlamudi: The device manufacturer needs to consider the limitations of bioresorbable materials, especially polymers because of their inferior strength compared to metals. They also need to consider the material’s reactivity with the tissue along with the absorption rate. The material’s properties, such as crystallinity and molecular weight, in addition to product design and environment where the product is going to be implanted all need to be contemplated. Further, the processing methods (molding and sterilization) must also be taken into consideration.
 
Fenske: How is additive manufacturing being used in the development and/or manufacture of bioresorbable devices?
 
Vadlamudi: Additive manufacturing is gaining ground slowly in the manufacture of bioresorbable devices. The main advantages are the ability to manufacture complex shapes and material savings. Design freedom is expanding in comparison to traditional subtractive and forming manufacturing processes. The FDA’s acceptance of additive manufacturing as one of the manufacturing processes will accelerate the development of bioabsorbable materials suited for additive manufacturing.
 
Fenske: Are there concerns with strength, durability, and/or function when it comes to using bioresorbable materials for orthopedic applications?
 
Vadlamudi: Obviously, bioresorbable materials are weaker in strength compared to the metals currently used in orthopedic industry. Bioresorbable materials serve similar functionality with added benefits of radiolucency, minimizing restenosis etc.
 
Fenske: Do you have any additional comments you’d like to share based on any of the topics we discussed or something you’d like to tell orthopedic device manufacturers?
 
Vadlamudi: Donatelle has proudly served the orthopedic industry for over three decades. Please visit our website to learn how we can help you bring your next device to market on spec, on time, and on budget.
 
Learn more about Donatelle’s bioresorbable capabilities here >>>>>