BioE/ME C117 Structural Aspects of Biomaterials

Course Overview

Professor Lisa A. Pruitt, Ph.D.Associate Dean of Virtual Learning and Outreach Education

Chancellor's Professor of Mechanical Engineering and Bioengineering Adjunct Professor of Orthopaedic Surgery, UCSF

Structural Aspects of Biomaterials

Class Structure

CLASS: Tu/Th: 12:30-2pm 203 McLaughlin Hallhttp://www.me.berkeley.edu/ME117

http://webcast.berkeley.edu

SKILLS LAB: Thursdays, 3:30-5:30,203 McLaughlin.

Prof. Lisa Pruitt, OH: Tues 3:30- 5:00 or by appointment, 5134 EH, lpruitt@meSenior Teaching Assistants: Jevan Furmanski OH: MW 5-6, 136 Hesse

Shikha Gupta OH;T, 136 HesseTeaching team: Cheng Li, Sara Atwood, Sheryl Kane

Course components: EXAMS (40%), DESIGN PROJECTS (30%), OUTREACH TEACHING PROJECTS (20%), ATTENDANCE (5%), QUIZZES (5%)

All HW is to be prepared professionally and submitted electronically. No late HW--NO EXCEPTIONS.

This year our class is webcast. Please use microphones when asking questions.

Books:Dowling, 3rd edition and personal bound lab notebook

Course Goals Assessment of structure and mechanical

functions of load bearing tissues and their replacements.

Examination of biocompatibility of biomaterials and host response to structural implants.

Quantitative treatment of biomechanical issues and constitutive relationships of tissues and their replacements.

Material selection for load bearing applications including orthopedics, dentistry, cardiology and reconstructive surgery.

Mechanical design for longevity of devices

Understanding of legal and ethical aspects of medical devices.

Development of professional skills: team work, technical writing, oral presentations, design, and teaching.

Lecture topics

Overview of medical devices

FDA regulatory issues, biocompatibility and sterilization technology

Biomechanical properties: isotropy/anisotropy, stiffness,

bending, buckling, multiaxial loading, yielding, fatigue, fracture, wear, corrosion, and design issues.

Clinical Aspects: Orthopedics, Dental, Cardiovascular, and Soft Tissue Reconstruction. Case studies.

Lab topics

• Professional Development: Technical writing, oral presentations, literature searches

• Design: Open-ended problem solving,team work, methodology, and assessment

• Teaching: Blooms taxonomy, outreach activities, assessments

Biomaterials and implants

• Replace component of living being

• Restore Function

• Harmonious interaction with host

• Biocompatibility

• Long-term structural integrity

Structural biological materials

Hard Tissues: Bone, enamel, dentin

Soft Tissues: Cartilage, tendon, ligament, vitreous humor,vasculature,skin, organs

Fluids: Blood, synovial fluid

Problems when used as an implant material: Infection, resorption, inflammation, rejection

Synthetic Biomaterial Classes

• METALS: Co-Cr alloys, Stainless steels, Gold, Titanium alloys, Vitallium, Nitinol (shape memory alloys). Uses: orthopedics, fracture fixation,dental and facial reconstruction, stents.

• CERAMICS: Alumina, Zirconia, Calcium Phosphate, Pyrolitic Carbon. Uses: orthopedics, heart valves, dental reconstruction.

• COATINGS: Bioglasses, Hydroxyapatite, Diamond-like carbon, polymers.

Uses: orthopedics, contact lenses, catheters, in-growth.

Biomaterial Classes cont.

• POLYMERS: Silicones, Gore-tex (ePTFE), polyurethanes, polyethylenes(LDPE,HDPE,UHMWPE,), Delrin, polysulfone, polymethylmethacrylate.

Uses: orthopedics, artificial tendons,catheters, vascular grafts, facial and soft tissue reconstruction.

• HYDROGELS: Cellulose, Acrylic co-polymers. Uses: drug delivery, vitreous implants,wound healing.

• RESORBABLES: Polyglycolic Acid, Polylactic acid, polyesters. Uses: sutures,drug delivery, in-growth, tissue engineering.

Applications of Biomaterials

• Orthopedics: artificial hips,knees, shoulders, wrists; intervertebral discs; fracture fixation; bone grafts.

• Cardiovascular: heart valves, PTCA balloons, pacemakers, catheters, grafts, stents.

• Dental: enamels, fillings,prosthetics, orthodontics.

• Soft tissue: wound healing, reconstructive and augmentation, occular.

• Surgical: staples, sutures, scalpels.

Orthopedic Implants

Dental Implants

Cardiovascular devices

LVAS: Pump Drive Unit

Soft Tissue Reconstruction

Challenges

• Biofixation and stability of an implant• Long-term wear and debris generation• In-vivo degradation through complex bio-chemi-

mechanical actions• Inert materials do not elicit “pro-active”

responses in the body• Solutions are often temporary for tissue

replacement