While choosing the right implant material is of utmost importance, as discussed in our previous Orthopedic Implant Series post, the significance of optimum surface treatment throughout the entire implant manufacturing process cannot be overstated. This relates not only to the right surface finish, but also total compliance with the specified tight dimensional tolerances.
The functionality of an orthopedic implant is determined by the perfect match between the various implant components. This depends, to a large extent, on the surface treatment procedure(s).
Fueled by more active lifestyles and increased life expectancy,the market for knee, hip, and other replacement body jointsis on the rise. With more than $19 billion in annual worldwidesales, implants for joint reconstruction make up nearly 40 percentof all orthopedic product sales.
Thanks to significant advancements in materials and new or improvedsurface finishing technologies, today’s artificial hips andknees can last more than 20 years, giving the recipient decadesof comfort and agility.
Parts that are finished using modern mass finishingand shot blastingmethods play a key role in extending the lifespan of orthopedic implants.
Rosler has extensive experience in these processes which often include cleaning, deburring/edge radiusing, surface smoothing, post-casting surface preparation, machining, CNC grinding, and, of course, final finishing. These finishing technologies make big differences in the quality and performance of such products.
worldwide sales at nearly $10 billion annually, there is a high demand for
spinal implants. These implants are subject to very specific and strict surface
finishing requirements to ensure longevity and fixation to bone.
Mass finishing and shot blasting play key roles in creating the right finish for spinal implants, not only for intermediate surface treatment after forging, casting, machining, additive manufacturing, etc., but also for placing the final surface finish before implantation.
Like mass finishing, shot blasting is an exceptionally versatile surface treatment technology. Its applications range from general cleaning after casting and forging to shot peening and, even, cosmetic blasting for placing a fine, matte finish on the work pieces.
For shot blasting of orthopedic implants Rosler Metal Finishing recommends mainly air and occasionally wet blasting systems. The blast media is accelerated by compressed air and thrown at the work pieces through a blast nozzle, creating an extremely precise blast pattern compared to turbine blasting. Another advantage of air blasting is that it can be used with metallic, mineral as well as organic blast media.
These attributes and many more make this surface finishing method particularly useful in the medical industry.
Mass finishing is a highly versatile finishing technology that can be used for a wide variety of different surface treatment operations including those in the medical industry. Therefore, it is no surprise that mass finishing processes are utilized at practically every manufacturing stage for all kinds of orthopedic implants.
Rosler Metal Finishing has decades of experience in mass finishing. In this installment of the Joint Reconstruction Series, we will compare the various machines used to provide precise finishing for endoprosthetic manufacturers.
Examples ofMass Finishing
Mass finishing is used for a variety of joint
replacement work pieces including:
Descaling and edge radiusing of hip stems, knee femorals, and other
implants after forging or casting, e.g. lost wax or investment casting.
Deburring and surface smoothing of various implants after belt or CNC
Final polishing of knee femorals, femoral heads, and the inside of
acetabular cups to Ra = 0.8 micro inches as the last finishing stage before
Shot blasting and mass finishing have become indispensable technologies for surface preparation and finishing of joint reconstruction implants. Their applications range from surface cleaning, deburring, edge radiusing after forging, casting, additive manufacturing, and machining to surface preparation for different kinds of coatings, shot peening for increasing the longevity of an implant, and placing an extremely smooth, high-gloss finish on the implants before they are inserted into the body.
Joint reconstruction implants allow millions of
individuals to regain mobility and reduce pain. Just as surgical skill is
required to implant these artificial joints, so is skillful construction and
finish of the joint components themselves.
Our Joint Reconstruction Series continues with an
overview of the most common materials used for these endoprosthetic implants.
The most common materials used for joint reconstruction implants are currently titanium and titanium alloys and cobalt-chromium alloys. Both materials are very tough, corrosion-resistant, highly biocompatible, and have proven themselves to be absolutely reliable.
With more than $18 billion in annual worldwide
sales, implants for joint reconstruction make up nearly 40 percent of all
orthopedic product sales. More active lifestyles and increased life expectation
continue to contribute to the rapid growth of this market segment.
Thanks to significant advancements on the material side and enhanced surface finishing technologies, artificial hips and knees can last more than 20 years before they must be replaced. Rosler Metal Finishing’sshot blasting and mass finishing capabilities are examples of processes and equipment that have and continue to evolve to accommodate the demand for increased endoprosthetics which are also known as orthopedic joint reconstruction implants.
These techniques play a key role in intermediate processing steps including cleaning, deburring/edge radiusing, surface smoothing, and surface preparation for coatings after casting, forging, machining, CNC grinding as well as placing the final finish on the implants before they are inserted.
It is not surprising that trauma implants, along with other medical devices, are subject to the most stringent quality standards. Any material defect or malfunction can have catastrophic consequences for a patient.
For implants, the two key issues for manufacturers to deal with are selecting the right material and attaining the required surface finish. The finishing requirements can range from simple cleaning or deburring to surface smoothing and high-gloss polishing. Components exposed to a lot of tensile and bending stress even undergo a shot peening process to improve their fatigue life.
Some implants must have a textured or “rough” finish to promote osseointegration, which is the attachment of surrounding bone tissue to the implant. Other trauma implants require a very smooth surface to prevent the bone from attaching itself to the implanted material.
We’ve created anotherexclusive surface finishing guidebookto cover this complex topic, in which we will discuss the surface finishing needs of trauma implants and the impact finishes have on their functionality and performance. Examples of mass finishing and shot blasting applications will also be presented followed by detailed machine reports of actual applications used in the industry today.
If you are interested in sending us your parts forFREE process development, contact us here.
Among the various technologies used for finishing the surface of medical instruments, mass finishing and shot blasting play a key role, not only as intermediate steps but also for placing the final, finishing touch on these components.
Besides the right material selection, surface treatment is an essential component of the overall manufacturing process of medical instruments. Only high-quality surface finishes guarantee the required functionality, high sterility, corrosion resistance, and absolute reliability that most medical components require, while also providing a satin, non-glare appearance.