BIOMATERIALS. What is a Biomaterial? Attention! Info on Term Projects. Anything in contact with human body?

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1 Week Topic Instructor 1 Biomedical Engineering World Dr. S. Takaç 2 Biomed. Instrumentation and Signals Dr. Ö. Birgül YOU 3 Medical Imaging ARE Dr. Ö. Birgül 4 Biomechanics HERE Dr. C. Evrensel Attention! Info on Term Projects Form groups of 3 5 Biomaterials Dr. P. Yılgör Huri Give names to Dr. Huri by next Wednesday, November 2nd, 17:30 6 Diagnosis Dr. D. Özel Demiralp 7 Nanomedicine Dr. A. Yılmazer Aktuna 8 Midterm Exam 9 Special topics in BME 1 Bioinformatics Selection of Project Topics Rules for writing and presenting a project 10 Special topics in BME 2 BME in Orthopedic Surgery Midterm week: Term Project topics will be assigned to each group You will prepare a poster and a short presentation You will present in the last 2 weeks of the semester 11 Special topics in BME 3 Sağlık Sektöründe Tıbbi Cihaz Teknolojileri 12 Special topics in BME 4 TBA Your posters will be displayed on the first floor for the rest of the year 13 Student Project Presentations Poster and Oral Presentations 14 Student Project Presentations Poster and Oral Presentations 1 Best poster award 2 BME101 Introduction to Biomedical Engineering BIOMATERIALS When does a material become a biomaterial? Doç. Dr. Pınar Yılgör Huri phuri@ankara.edu.tr Ankara University Department of Biomedical Engineering 3 4 Anything in contact with human body? What is a Biomaterial? Abiomaterialis any substance that has been engineered to interact with biological systems for a medical purpose - either therapeutic Treat Augment a tissue OR function of the body Repair Replace 5 - or diagnostic use 6 1

2 Biomaterials are used for a variety of purposes within the body 8 Annual biomaterial use; Expenses associated with biomaterial use; 10 Biomaterials Science Multidisciplinary: Biomaterials research and development have been stimulated and guided by advances in: Materials science Cell and molecular biology Medicine Chemistry Physics Engineering History of Biomaterials Gold, ivory and wood in dentistry and prosthesis >3000 years ago First prosthesis in history (Egypt) Nacre from sea shells by Mayans.. with no knowledge of sterilization, toxicology, inflammation, corrosion, biodegradation, etc. First sutures on mummies using animal tendons 11 2

3 History of Biomaterials 1860: Aseptic surgery 1900: Bone plate, 1930: Artificial joints Synthetic plastics in use - It was observed during the 2WW that shards of plastic from shaddered canopies found in war pilots eyes were compatible with the body (no reaction) History of Biomaterials 1961: PE and stainless steel hip prosthesis Ridley (ophthalmologist) examined the pieces and found that it is PMMA This material was used to fabricate intraocular lenses (and first hard contact lenses) > 7million IOL applications today worldwide Evolution of Biomaterials 1st generation biomaterials (>1950) Aim: Bioinertness (silicon, PE, PU, PP, PMMA) 2nd generation biomaterials (>1980) Aim: Bioactivity(PLA, PGA, PLGA, PHEMA) 3rd generation biomaterials (>2000) Aim: Functional tissue regeneration Gene and cell activation Biodegradable polymers designed at the molecular level Structural support Biodegradable implants integrating w/ body Tissue engineered products The success of a biomaterial is related to several factors including; Material related properties General condition of the patient Surgical technique and proper follow up Biomaterial should: Retain physical properties Be non-toxic Be non-carcinogenic Be anti-allergic Have long service time Retain functionality during use Be easily sterilized Be biocompatible Bulk properties: Chemical composition and structure, Purity, leachables Surface properties: Porosity, Geometry, Hydrophilicity, Surface charge Mechanical properties: Toughness, Elasticity, Stability Long term structural integrity: Load, Fatigue performance, Abrasion and corrosion resistance Biocompatibility ability of a material to perform with an appropriate host response in a specific application Thrombosis Hemolysis Inflammation Infection Carcinogenesis Irritation Host Response / Foreign Body Reaction Biomaterials: From Bench to Bedside Idea Identification of the problem Design Material Synthesis Material Testing (in vitro and in vivo) Production Sterilization / Packaging Material Tests Shelf life, stability Regulation Patient Clinical application and further tests 3

4 Example: Evaluation of the success of a biomaterial Types of Biomaterials What are the necessary characteristics of a bone plate material? Things to ask: Does it have sufficient mechanical stability? Is it chemically stable? Is it changing over time? Is engineering design appropriate? Is the density and weight compatible with bone? Is the fatigue time acceptable? Is the plate accepted by the tissue? Is it acceptable pharmacologically? Whatisthecost? Is it reproducable? Is it possible to produce at large scale? Metals Metals: Generally used in hard tissue repair and blood contacting devices Co-Cr alloys Au and Pt Silver-tincopper alloy Stainless Steel Titanium alloys Heart valve, dental prosthesis, ortopedic fixation devices, stents Dental filling Dental amalgam Dental prosthesis, ortopedic fixation devices, stents Heart valve, dental prosthesis, joint prosthesis, screws Aluminium oxides Bioactive glass Calcium phosphates Ceramics Joint prosthesis, orthopedic load-bearing implants, implant coating, dental implants Ortopedic and dental implant coatings, dental implants, bone and facial implants Ortopedic and dental implant coatings, dental implants, bone implants and bone fillers Ceramics: Generally used in bone and dental-related applications due to compositional similarity Have similar chemistry and mechanical properties with natural bone More often used as a part of orthopedic implant (coating material) due to high wear resistance As dental materials (crowns, dentures) 24 4

5 Poly(HEMA) PDMS PE PEG PET PCL PLGA PMMA PTFE PP Alginate Chitosan Collagen Elastin Fibrin HA and GAG Polymers Contact lens Brest prosthesis, contact lens Ortopedic joint implants Wound dressing Vascular graft, suture Drug release, biodegradable suture Biodegradable suture Bone filler Vascular graft, suture Suture Wound dressing Wound dressing Tissue engineering scaffold Skin regeneration matrix Tissue adhesive Orhopedic regeneration matrix Polymers: Versatile; used for different applications PGA, Vicryl Nylon Sutures Artificial Skin Surgical Tapes IOL Tissue Engineering Isolate cells from the patient Produce the scaffold to guide the tissue production Seedthecellsontothescaffoldsandgrowthetissuesinbioreactors Transplant the tissue engineered graft back to the patient CAD/CAM can be used to produce scaffoldof the human ear (auricular cartilage) seeded with chondrocytesand cultured in vitro (cell culture) and in vivo (in the animal model) Biomaterials Related Courses in Our Curriculum BME 341 Biomaterials BME332 Biomaterials and Biomechanics Lab BME441 Cell and Tissue Engineering BME447 Introduction to Polymer Engineering BME444 Controlled Release Systems and Drug Targeting

6 Group information by next Wednesday! 31 6