Fast Casters - Formal Design Review March 2, 2006 Rene Chen Byron Hsu Kimberly Kam Kelsey Vandermeulen Lisa Witmer

3/2/ Brief Update Speed Skate Blade Speed Skate Blade Titanium blade will likely shatter Titanium blade will likely shatter Final Decision Final Decision 3D printed bone scaffold 3D printed bone scaffold

3/2/ Current Scaffolds Jim Serdy 12/28/04

3/2/ Project Goal Improve the mechanical properties of bone scaffolds through optimizing the composition of the printing powder

3/2/ Desired Scaffold Properties: Biocompatibility Materials candidates Materials candidates PLGA – poly lactic acid-co-glycolic acid PLGA – poly lactic acid-co-glycolic acid PCL – poly caprolactone PCL – poly caprolactone TCP – tricalcium phosphate TCP – tricalcium phosphate HA – hydroxyapatite HA – hydroxyapatite

3/2/ Desired Scaffold Properties: Mechanical Elastic modulus varies with age and location Elastic modulus varies with age and location Target Range: GPa Target Range: GPa Uniaxial compression and tension three orthogonal directions Uniaxial compression and tension three orthogonal directions

3/2/ Desired Scaffold Properties: Architecture Channel Geometry Channel Geometry um um Waffle structure Waffle structure Cell and vascular in-growth Cell and vascular in-growth Jim Serdy 12/28/04

3/2/ Current MIT Research Current MIT Research Jim Serdy  Lab of Manufacturing and Productivity Jim Serdy  Lab of Manufacturing and Productivity Has been working with bone scaffolds Has been working with bone scaffolds MGH and Cleveland Clinic MGH and Cleveland Clinic Agreed to supervise our work in his lab Agreed to supervise our work in his lab Our work will explore areas of his interest as well Our work will explore areas of his interest as well

3/2/ Alpha 3D Printer Laboratory of Manufacturing and Productivity Laboratory of Manufacturing and Productivity

3/2/ Jim Serdy’s Research Patent Patent PLGA + PCL + sucrose + lactose + water PLGA + PCL + sucrose + lactose + water Dissolves sucrose and lactose to form pores Dissolves sucrose and lactose to form pores Vacuum + chloroform to bind polymer Vacuum + chloroform to bind polymer

3/2/ Improvements Bone scaffold is too soft/compliant Bone scaffold is too soft/compliant Increase the stiffness by incorporation of higher TCP concentrataions Increase the stiffness by incorporation of higher TCP concentrataions

3/2/ Jaw Bone Scaffold

3/2/ Risks Risk 1: Time Limitations Risk 1: Time Limitations Formulation of the powder can be a very complicated process by itself Formulation of the powder can be a very complicated process by itself Iteration time of powder composition-printing-visual and mechanical testing Iteration time of powder composition-printing-visual and mechanical testing Planned 4 weeks per cycle Planned 4 weeks per cycle Risk 2: 3D printer reliability Risk 2: 3D printer reliability Trouble shooting the 3D printer is time consuming Trouble shooting the 3D printer is time consuming Single compatible machine Single compatible machine While trouble shooting the 3D printer, we can be formulating the powder and working on the jaw bone through CAD, etc. While trouble shooting the 3D printer, we can be formulating the powder and working on the jaw bone through CAD, etc. Work ahead of time, allow buffer time Work ahead of time, allow buffer time

3/2/ Key Decision Points Desired mechanical properties Desired mechanical properties Strategies of approaching desired properties Strategies of approaching desired properties Powder compositions to test Powder compositions to test Balancing stiffness and density Balancing stiffness and density

3/2/ Materials and Costs Product Molecular Formula Molecular Weight CAS Number Company Product # Price (USD) Available to ship Hydroxyapatite(HA) Ca 5 (PO 4 ) 3 OH Sigma- Aldrich G G Poly(lactic-co- glycolic acid) (PLGA) Very expensive Polycaprolactone(PCL) ( C 6 H 10 O 2 ) n ~65, Sigma- Aldrich G G G Date not available Poly(vinyl alcohol) (PVA) [-CH 2 CHOH-] n [-CH 2 CHOH-] n 13, , Sigma- Aldrich G G KG KG Tricalcium phosphate (TCP) Ca 3 (PO 4 ) Sigma- Aldrich G-F58.20 Date not available G-F

3/2/ Project Timeline

3/2/ Resources 3D Printer: James Serdy’s lab 3D Printer: James Serdy’s lab Room Room Laboratory for Manufacturing and Productivity Laboratory for Manufacturing and Productivity Workstations for using Solidworks and Ansys: Workstations for using Solidworks and Ansys: Room Room SEM: Room ? SEM: Room ?

3/2/ Thank You Questions? Questions?