Materials Science Notes PDF

# Materials ## Orthopedics ### Materials * **Polymers:** * UHMWPE: hip and knee, joints. * PMMA * Polyester: adhesion * Polycarbonate * Polyurethane linear segments * PP / PDMS: prosthesis fingers * Acial Austenitic * **Metals:** * Cr-Cobalt alloys * Titan...

# Materials ## Orthopedics ### Materials * **Polymers:** * UHMWPE: hip and knee, joints. * PMMA * Polyester: adhesion * Polycarbonate * Polyurethane linear segments * PP / PDMS: prosthesis fingers * Acial Austenitic * **Metals:** * Cr-Cobalt alloys * Titanium alloys * Aluminum: head femur, prosthesis * Zirconia: femoral heads, prosthesis * ZTA / EPTA ## Biodegradable Materials ### Polymers * **Natural:** * Proteins: collagen, fibrin, fibroin (silk in years) * Polysaccharides: hyaluronic acid, chitin * **Synthetics:** * Polyester: PLA, PGA, PCL * Polyurethanes: some types as polyester - urethanes ### Ceramics * Bioglass, CAP, HA (in long term) ### Metals * Zinc and magnesium ## Engineering Tissue Materials (Scaffolds) ### Polymers * **Natural:** * Collagen * Silk. * Gelfoam for hemostasis * Hyaluronic acid (hyaluronan) * **Synthetics:** * Polyester: PLA, PGA, PCL * Polyester - urethanes * Biologic: decellularized matrices ### Ceramics * Calcium phosphates ### Metal * Biodegradable (metals) ## Sutures * **Absorbable:** * Collagen (catgut) * Polyester: PLA, PGL, PGLA, PCL * **Non Absorbabale:** * Silk * Polypropylene * PTFE ## Contact Lenses * Hydrogel: PHEMA, PVA * Silicone: PDMS ## Stents * **Rigid:** * PMMA: also for ocular aesthetics, silicone * PMMA, PHEMA, PDMS * Ocular prosthesis: PMMA * **Drug release:** * Cr-Co, Nitinol + polymeric component: PLA, PGA. * **Not medical:** * Steel - inox * Nitinol, Cr-Co alloy, PET/PU/PTFE coating. ## Valves * **Chirurgical mininvasive:** Nitinol, Cr-Co alloy with PET/PU/PTFE coating * **Aortic Aneurysm:** Nitinol, Cr-Co alloy with PET/PU/PTFE coating. ## Anuloplastica Rings * NiTinol, Silicone, Carbomio, Dacrom ## Hernia Containment Nets * **Biologic:** bovine, porcine, human * **Synthetic:** PP, PET, PTFE/PLA, PGA ## Prosthetics * **Knee:** Cr-Co, (femoral component), UHMWPE: (spacer), Titanium alloy (tibia) * **Fingers:** Titanium Alloy (light), peek IPVS, silicone, PP. * **Hand:** titanium, peek IPVS, silicone, PP. ## Soft Tissue Filling * Hyaluronic acid, PMMA, (hydroxyapatite of calcium) + SILICONE for aesthetic surgery. ## Implantable Devices * **Cochlear:** Silicone, Titatium, ceramic materials. * **Diabetes:** Steel. * **Cannule tracheal:** PTFE, PP (cannula), PU, PVC (catheter) * **Catheters:** PVC plasticised, PU, HDPE, silicone. * **Interspinous Distancer:** TiAlVo, Peek * **Dental implant:** PMMA. # Cardiocirc ### Materials That Crosslink * **Anhydrous:** * **PLA:** controlled drugs release, daily contact lenses. * **PHEMA:** Hydrophilic, hydrogel, contact lenses * **PLU:** hydrophilic if reticulated hydrogel. * **Alginate:** hydrogel that can be loaded with drugs. * **Fibrinogen/Fibrin** not a hydrogel, but technically crosslinks. * **Collagen:** recollected to recover its properties, avoiding the quick degradation, allowing the obtainig of bioabsorbable properties. ## Materials That Reticulate * **Synthetic:** * **PVA:** control the release of drugs, daily contact lenses, bioresorbable * **Natural:** * **Proteins- collagen, fibrin, fibroin, silk:** * **Polysaccharides - hyaluronic acid, chitin:** * **Synthetics:** * **Polyesters such as PLA, PGA, PCL:** * **Polyurethanes (some types such as polyester-urethane)::** * **Biologic:** Decellularized matrices ## Materials for Engineering Tissues (Scaffolds) * **Natural:** collagen, silk * **Synthetics:** Polyester: PLA, PGA, PCL, polyester-urethanes ## Cardiovascular Prosthesis * **Stelo:** TiAlVo light, less rigid → osteointegration * **CoCrMo:** rigid, heavy, cemented. * **Cup in the bone:** Cr / Ti. * **Components Acetabular:** femoral head made of alumina * **Femoral cup:** UHMWPE. ## Cardiac Valves * **Polymers:** Dacrom, polyurethanes * **Ceramics:** Carbomio turbostratico * **Metals:** Cr-Co per def plastica, Nitinol * **Biology:** porcine / bovine * **Homo / Autograft:** Tissue ## Vascular prosthesis * **Pet (polyester, Dacron-fabric) + polyurethanes:** in development * **PTFE (Goretex)** * **Autograft:** saphena, mammary * **Heterograft:** porcine, bovine * **Homograft** ## Materials work like yarn * **Polyethylene:** PET (Dacrom) * **Polyurethanes:** * **Polypropylene:** * **Polyethylene:** HDPE, Tyvec. ## Cardiocirc * **Polymers:** * PVC plasticized: blood containers, intravenous, tubes. * PDMS (silicone) - elastic, flexible (for its elastomeric behavior) - lenses, small prothesis (fingers), catheters, aesthetic surgery (for implant coclear) * PMMA Amorphous, transparent, strong (for its elastomeric behavior) - bone cement, intraocular, rigid lenses (for aesthetic prosthesis) (soft tissue filler) * PHEMA: amorphous, polar - (hydrogel) - contact lens. * PP: rigid, crystalline, spun (yarns) - suture, hernia membrane, finger articulations (+ for diabetic device) * PTFE: high molecular weight, physiologically inert, hydrophobic, not resisitant to wear; vascular prothesis, suture yarn, gauze. ## Prosthesis * **Pet** (Polyester, Dacron-fabric) + polyurethanes in development * **PTFE (Goretex)** * **Autograft** - saphena, mammary * **Heterograft **- porcine, bovine * **Homograft** * **PP**, **PET**, **PTFE/PLA**, **PGA**, **PU** - for big vascular prothesis, yarn, gauze ## Materials suitable for yarn work * **Polyethylene:** PET (Dacrom) * **Polyurethanes** * **Polypropylene** * **Polyethylene** HDPE, Tyvec. ## Requirements of project ### Orthopedic Prothesis * Resistance to mechanical compression * Resistance to fatigue. * Resistance to wear and corrosion * Sterilization ### Cardiovascular prosthesis * Biocompatibility * Suturbaility * Ease of implant * Physiologically inert (not degrading) * Duraability * Resistance to fatigue. * Radio opacity ### Hip prosthesis * Allows for natural movement. * Implantable and replaceable * Primary and secondary stability * Mechanical resistance and fatigue * Resistance to corrosion and wear * No periprosthetic capsule formation ### Valvular prosthesis * Various sizes * Implantable and replaceable * AP < 5mm HG. * Passive mechanism. * Static reflux. * Radio opacity * No coagulation * No hemolysis * No formation of abnormal fibrous capsules * Durable, should not degrade * Resistance to mechanical fatigue ### Vascular prosthesis * Implantable and sutureable * Various sizes * Flexible * Resisitant to fatigue. * Mechanically compatible * Stable, not degrading * Coagulation under control * Radio opacity * Compatible sizes ### Scaffold * Porosity > 70% * Pore size ≈100µm * Interconnected pores * Sterilizable * Degradable with controlled kinetics * Biocompatible. * Bioresorbable in controlled kinetics ### Bioink * Biocompatible * Hydrogel, gelatin or alginate * Rheological properties allows control of degradation * Mechanical properties and stability guarantee biomimicry with tissue. * It will be respecting the endogenous tissue. ### Biorector * Parts in contact highly compatible and sterililzed. * Allows for varying physical fields, versatile * Small, easy to assemble * Automatic and standalone ## Effects of metals * **Nickel:** confer resistance to fatigue, under the solicitations of strain and corrosion. * **Chrome:** creates oxides that are particularly effective, resistance to corrosion.