gyti.techpedia@sristi.org
Low-cost Indegenously Developed Bioresorbable Medical Bone Screws For Bone And Soft-tissue Fixation Applications
Project Description :

(a) preamble: currently available bioabsorbable implants for fixing soft-tissue injuries (like anterior cruciate ligament tears) and bone anomalies (like fractures) are all-imported, costly and hence, beyond reach of 80% of indian demographics. biocomposite devices (current state of the art implants) also suffer from stress-shielding (mechanical properties mismatch with soft tissue graft), implants-associated infections and improper bone remodeling. since these devices lack inherent antibacterial, anti-resorption activity, it demands antibiotic and bis-phosphonate incorporation, adding to overall cost burden. hence, there is a strong need for indigenously developing low-cost resorbable orthopedic fixation devices with advanced functionality biomaterial. innovator team has developed novel orthopedic biocomposite material comprising of silk fiber-reinforced, magnesium oxide nanofillers-loaded bioresorbable polycaprolactone having tunable mechanical (tensile strength= 15-30mpa and modulus= 0.2-1.5gpa) and improved biological properties (biodegradation, bioactivity, biocompatibility and hemocompatibility) with antibacterial and anti-resorption activity (imparted by mgo nanoparticles). we have successfully demonstrated proof-of-concept for stress-matched resorbable medical bone screws with novel design using as-developed advanced, economical biomaterial (mgo-silk-pcl composite) with in-house manufacturing process (custom-fabricated injection molding molds) and tested its biosafety in pre-clinical rat models. hence, our innovative technology holds the promise to benefit lives of millions of needy patients from developing countries with orthopedic anomalies, thus, making these effective medical care devices affordable to masses. (b) technology innovation: (1) novel orthopedic biomaterial components impart synergistic effect by combining characteristic advantages of each as follows: (i) pcl was selected as bulk polymer owing to its following advantages over plla, plga: a) tunable mechanical properties mechanical property (young’s modulus) of human tissues viz. cancellous bone, ligament, tendon, etc. ranges from 0.02-1.5 gpa, most of polymers viz. plla, plga, etc. ranges from 2-3 gpa which is well above upper limit of required range while that pcl is 0.2-0.5 gpa which can be tuned to match required mechanical properties by required concentration of filler reinforcement with ceramic particles (mgo) and natural fiber (silk). b) in-expensive biocompatible, bioresorbable polymer with non-toxic degradation byproducts and good thermo-plasticity, moldability, hence, there are various fda-approved pcl-made biomedical devices; c) being slow degrading polymer under in-vivo milieu, it’s degradation products are less prone to elicit acidic environment in surrounding unlike plla, plga, etc., d) one of the most extensively researched polymer for fabricating scaffolds for plethora of biomedical applications, e.g. nerve repair, tendon regeneration, skin tissue engineering, bone regrowth scaffolds, etc. (ii) degummed silk is fda-approved natural fiber; extracted from bombyx mori improves mechanical properties (ductility, stiffness) of pcl by reinforcement. (iii) mgo nanoparticles are explored as potential ceramic fillers to impart bioactivity and mechanical properties of pcl, tapping its unique antibacterial property against gram negative bacteria like pseudomonas aeruginosa and gram positive bacteria like staphylococcus aureus (major causative pathogens responsible for implant-related infections). mgo also imparts anti-resorption property to composite biomaterial by improving bone remodeling. (2) overall cost of prototype screw is very low as compared to marketed products owing to following factors: i) use of cheaper raw materials (pcl is 1/5th the cost of plla or plga-sigma aldrich, also precursors for synthesis of mgo nanoparticles and degummed silk fibers i.e. mgcl2 salt, naoh pellets and bombyx morri cocoons, respectively, are very much inexpensive and readily available. ii) in-house capability for injection molding polymeric devices using custom-fabricated molds (developed from local machine tool workshop) and micro-compounder and injection molding facility. (iii) screw head shape is designed hexagonal: regular allen key can be used to drive our bone screw (no need of specialized screw drivers like other marketed products) (iv) eliminating dependence of antibiotic and bis-phosphonate implant coating (3) one technology platform for all devices: as-developed novel biomaterial (mgo-silk-pcl) composition is being injection molded into custom-designed molds to fabricate prototype bone screws. this unique technology platform can be further explored to indigenously manufacture other bone soft tissue fixation devices like plates, suture anchors, pins, buttons, staples, clips, tacks, arrows, washers, etc.

 
Other Photos :
 

Date :31-12-2016
FIGURE CAPTIONS: 1) COVER FIGURE- PROOF-OF-CONCEPT PROTOTYPE: (I) A) CAD model of copper electrode, B) Reference bone screw and copper electrode (intended to be used in Electrode Discharge Machine-EDM to fabricate injection molding mold) fabricated from CAD model by CNC lathe machine, C) Special injection molding mold (pocket-pin assembly) for fabricating cannulated and non-cannulated bone screw; (II) Prototype bone screw made up of as-developed MgO-silk-PCL biomaterial with cannulation (Allen key fitting sizes 3mm and 4mm) and non-cannulated (3mm Allen key fitting); 2) PROBLEM STATEMENT: Biomaterials trend shift from metallic to bioresorbable devices and current limitations of bioresorbable (polymer and biocomposite) orthopedic devices; 3) OUR INNOVATION: Unique platform technology solution i.e. novel advanced composite biomaterial and custom-designed molds, capable of developing array of resorbable orthopedic implants; 4) PRELIMINARY DATA: characterization studies on MgO-silk-PCL composite biomaterial screw (in-vitro, ex-vivo and in-vivo); 5) SAME AS 1); 6) ADVANTAGE OVER COMPETITORS: Comparison of as-developed MgO-silk-PCL composite prototype bone screw with currently marketed bone screws (Smith & Nephew) of different biomaterials (metal, polymer and composite); 7A and 7B) PROTOTYPE BROCHURE: depicting various types of prototype bone screws developed, its unique features and future scope of advanced biomaterial and as-developed technology platform for developing an array of resorbable orthopedic/ other clinical application products using micro-compounding and injection molding AWARDS AND RECOGNITIONS: 1) Received ‘Certificate of Excellence’ at Samsung Innovation Awards 2016 organized by Samsung R&D Institute India- Bangalore for innovation ‘Low-cost indigenously developed bioresorbable bone screw’ and was invited as guest speaker to share ‘Research and Innovation Best Practices’ for said innovation project 2) Winner of ‘Student’s Excellence Award in Social Innovation 2016’ given by Lions Club North Bombay for our innovation on ‘Resorbable medical bone screw for bone-soft tissue fixations’ and received cash award of INR 1,00,000 and Trophy. 3) Selected as only Indian student for Talent Technology Entrepreneurship Program (TEP 2016) in Spain for leading medical device development project along with entrepreneurship training 4) Recipient of grant-in-aid from Department of Health Research, ICMR (Inter-sectoral convergence & coordination for promotion and guidance on health research) for developing orthopedic biomaterial FRUGALITY OF INNOVATION: 1) In-house development capability: i) Well-established manufacturing process: Preparation of biocomposite material from micro-compounder and injection molding facility available at IIT Bombay lab, ii) Locally manufactured parts for fabrication and testing: We have fabricated custom-designed injection molding mold to prepare bone screws (cannulated and non-cannulated) and jigs for biomechanical studies (pull-out strength testing) at local tool workshop facility using CNC lathe machine. Thus, we are capable of developing bioresorbable implant of any size and shape for desired biomedical application, by changing shape and size of cavity in the injection molding mold, thus, proving cost-effective technology platform to indigenously develop different bioabsorbable implants 2) Inexpensive and readily available/ easily synthesizable raw materials like cocoon silk, PCL and MgO nanoparticle, hence, affordable orthopedic biomaterial has been developed and tested 3) Obviating need of antibiotic and bis-phosphonate coating owing to MgO nanoparticles, thus, bioactive filler itself serving anti-bacterial and anti-resorption role, hence, reducing cost burden on final product In summary, our bone screw product is proposed to be marketed at half of the cost of currently available resorbable bone screw implants.


 
Project Details :
  • Date : Dec 30,2016
  • Innovator : AJAY VIJAY SURYAVANSHI
  • Team Members : MR. KUNAL KHANNA
  • Guide Name : DR. ROHIT SRIVASTAVA, DR. JAYESH BELLARE
  • University : Indian Institutes of Technology Bombay
  • Submission Year : 2017
  • Category : Biomedical Engineering
Share Project :