BioEME C117 Structural Aspects of Biomaterials

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Structural Aspects of Biomaterials

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
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Class Structure

• CLASS Tu/Th 1230-2pm 203 McLaughlin Hall
• http//www.me.berkeley.edu/ME117
• http//webcast.berkeley.edu
• SKILLS LAB Thursdays, 330-530,203 McLaughlin.
• Prof. Lisa Pruitt, OH Tues 330- 500 or by
  appointment, 5134 EH, lpruitt_at_me
• Senior Teaching Assistants Jevan Furmanski OH
  MW 5-6, 136 Hesse
• Shikha Gupta OHT, 136 Hesse
• Teaching 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.
• BooksDowling, 3rd edition and personal bound lab
  notebook

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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.

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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.

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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

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Biomaterials and implants

• Replace component of living being
• Restore Function
• Harmonious interaction with host
• Biocompatibility
• Long-term structural integrity

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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

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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.

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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.

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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.

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Orthopedic Implants
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Dental Implants
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Cardiovascular devices
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LVAS Pump Drive Unit
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Soft Tissue Reconstruction
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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