Micro-moulding is known for its variety of challenges, especially when it comes to micro medical parts. At Polymermedics, we are constantly improving our production capabilities to ensure that our projects adhere to our high-quality standards, no matter how complex they might be. That is the very reason why Polymermedics has become a leading medical injection moulding manufacturer and was chosen to manufacture C-Point – the world’s first self-sealing obturation points.
Micro-moulding and its challenges
Micro-moulding can often pose a challenging task for an engineer. Because of the precision required to work with such minuscule size, it is necessary to have specific machinery that successfully deals with extremely small tolerances and enables one to manufacture products that are as small as specks of dust.
“If micro-moulding is so complicated in its most standard form, one might imagine the challenges that attribute to medical micro-moulding”
No matter where the manufacturing takes place and how many professionals are scrutinizing the design, moulders will always have to take steps to tackle any arising problems. Below are some of the major roadblocks that engineers often face during design and production processes:
- 1De-facto, sprue and runner systems can aggregate up to 75% or even more of the shot;
- 2In order to reduce viscosity, higher injection speed is required;
- 3There is a rising need for significant pressures to secure that the material fills the part at the precise temperature;
- 4To manufacture these high-performance miniature parts, specific materials are essential. The most common materials include polyamide-imide, polyetherimide, liquid-crystal polymer, PPS, and new cyclo-olefin (COC) resins.
Packing, inspecting and testing the product after it is manufactured brings a new set of concerns. Working with such small parts eliminates any room for errors and process stability is a must. If micro-moulding is so complicated in its most standard form, one might imagine the challenges that attribute to medical micro-moulding. In fact, these days, the medical device industry continues to grow exponentially, with a rising demand for innovative, smaller, onward micro medical devices.
And medical micro-moulding has its own challenges: from selection of the right medical grade plastics, to required high quality standards and clean room conditions. Micro-moulding can be helpful in such fields as dentistry, urology, oncology, interventional cardiology peripheral medicine and many more. Micro-moulded products are used to save and improve the lives of patients.
“We had to manufacture a product that would supercede gutta percha as the standard of endo treatment”
Case study – CPoint
The Challenge
Since Polymermedics has 40 years of assorted expertise in medical moulding, with all the cumulative knowledge, we were ready to challenge ourselves. CPoint was the best fit for this endeavor. We embarked on a revolutionizing project, which meant a high level of responsibility, long and meticulous R&D, and intricately bespoke solutions. We had to manufacture a product that would supercede gutta percha as the standard of endo treatment.
The product that we have manufactured is self-sealing obturation points, which are used for root canal treatment. CPoints have a two-component design: a central core and a hydrophilic polymer coating that expands to conform to canal irregularities.
Manufacturing a product as complex, and with such low tolerances as CPoint, brought noteworthy engineering challenges. It marked an absolutely new level of manufacturing with ultra-precise tooling required:
- 1To build an ultra-precise tool – a step up for the team of engineers;
- 2Micro-mould a core for the center of the CPoint product, to ensure that the expansion of the part is only radial;
- 3Ensure clear-cut accuracy of the chemical mix for the coating, using bespoke blends of materials.
The Solution
Polymermedics professionals carefully planned each stage of design and production to resolve each of the challenges. The Wittman Battenfeld Micromoulding Machine and Battenfeld Injection Moulding Machine were chosen to manufacture the Cpoint. The quality of the manufacturing process and its outcomes were ensured through ISO13485 standards. Using data analysis techniques and tools, such as Six Sigma and DOE we were able to identify any issues and address them during manufacturing.
The success was evident:
- 1The manufactured product has a central core to provide excellent handling characteristics and a hydrophilic polymer coating, bonded to the central core, which radially expands to seal all types of canals;
- 2The inner core of C-point is a mix of two proprietary nylon polymers: Trogamid T and Trogamid CX.
- 3Hydrophilic coating is a copolymer of two monomers, acrylonitrile and N-vinyl-pyrrolidone, NVP, polymerized and cross-linked using allyl methacrylate and a thermal and UV active initiator;
- 4The product passed all assessments for certification and was successfully CE marked.
“This project has enabled us to further explore our capabilities and use the gained expertise to confidently undertake projects to manufacture most sophisticated products for any industry”
Summation
The case has proven that Polymermedics has all the means necessary to undertake most any project and deal with its complexities. The CPoint has opened a new era for endodontics: it manages to accurately fit even the most complex root canal profiles generated by any dentistry file system, and reliably provide a superior seal once the product is put in place. It is biocompatible without being biodegradable, to ensure a lifetime of wear.
This project has enabled us to further explore our capabilities and use the gained expertise to confidently undertake projects to manufacture most sophisticated products for any industry. At Polymermedics, we are proud to manufacture the world’s first self-sealing obturation points.
