title: Brittle and ductile adjustable cement derived from calcium phosphate cement/polyacrylic acid composites.
abstract: OBJECTIVE
  Bone filler has been used over the years in dental and biomedical applications. The present work is to characterize a non-dispersive, fast setting, modulus adjustable, high bioresorbable composite bone cement derived from calcium phosphate-based cement combined with polymer and binding agents. This cement, we hope, will not swell in simulated body fluid and keep the osteogenetic properties of the dry bone and avoid its disadvantages of being brittle.
  
  
  METHODS
  We developed a calcium phosphate cement (CPC) of tetracalcium phosphate/dicalcium phosphate anhydrous (TTCP/DCPA)-polyacrylic acid with tartaric acid, calcium fluoride additives and phosphate hardening solution.
  
  
  RESULTS
  The results show that while composite, the hard-brittle properties of 25wt% polyacrylic acid are proportional to CPC and mixing with additives is the same as those of the CPC without polyacrylic acid added. With an increase of polyacrylic acid/CPC ratio, the 67wt% samples revealed ductile-tough properties and 100wt% samples kept ductile or elastic properties after 24h of immersion. The modulus range of this development was from 200 to 2600MPa after getting immersed in simulated body fluid for 24h.
  
  
  CONCLUSIONS
  The TTCP/DCPA-polyacrylic acid based CPC demonstrates adjustable brittle/ductile strength during setting and after immersion, and the final reaction products consist of high bioresorbable monetite/brushite/calcium fluoride composite with polyacrylic acid.
authors.affiliation: Faculty of Dentistry, Kaohsiung Medical University, 807 Kaohsiung, Taiwan. chenwc@kmu.edu.tw
authors.forename: Wen-Cheng
authors.initials: WC
authors.lastname: Chen
authors.forename: Chien-Ping
authors.initials: CP
authors.lastname: Ju
authors.forename: Jen-Chyan
authors.initials: JC
authors.lastname: Wang
authors.forename: Chun-Cheng
authors.initials: CC
authors.lastname: Hung
authors.forename: Jiin-Huey
authors.initials: JH
authors.lastname: Chern Lin
mesh_terms: D020341:Absorbable Implants; D000180:Acrylic Resins / Q000737:chemistry*; D001843:Bone Cements / Q000138:chemical synthesis*; D002124:Calcium Fluoride / Q000737:chemistry; D002130:Calcium Phosphates / Q000737:chemistry*; D003799:Dental Stress Analysis; D055119:Elastic Modulus; D006244:Hardness; D008422:Materials Testing; D044367:Phase Transition; D013644:Tartrates / Q000737:chemistry; D013718:Tensile Strength; D014867:Water
chemical_list: D000180:Acrylic Resins; D001843:Bone Cements; D002130:Calcium Phosphates; D013644:Tartrates; C485830:tetracalcium phosphate; D014867:Water; C485829:calcium phosphate, dibasic, anhydrous; D002124:Calcium Fluoride; C029768:tartaric acid