Biomechanical testing of alloplastic PMMA cranioplasty materials.
Alloplastic cranioplasty techniques using polyfmethylmethacrylate (PMMA) are a common method of restoring lost cranial bone. Numerous compositions of PMMA exist for this application, using either intraoperatively cured solid compositions or preoperatively fabricated porous custom implants. Although all of these PMMA materials feel solid by palpation, the amount of cranial protection that they provide has never been precisely evaluated. Whether differences exist between the differing PMMA cranioplasty materials likewise is unknown. An impact resistance test was performed on uniform-size blocks of differing PMMA materials of representative cranial thickness using American Society of Testing and Materials (ASTM) method D 3029-78. Based on mean failure weights of 3.9 lb (Cranioplast), 4.2 lb (Cranioplexx), and 4.0 lb (HTR polymer), all of these materials are comparatively the same in impact resistance. Precured porous PMMA, despite having 30% to 40% less material, offered no less impact resistance. Based on projections to cranial bone, PMMA materials appear to offer protection similar to that of native osseous tissue.
Eppley
Barry L
BL
Department of Plastic Surgery, Indiana University School of Medicine, 702 Barnhill Dr., No. 3540, Indianapolis, IN 46202, USA. beppley@iupui.edu
D001696:Biomechanical Phenomena; D018786:Bone Substitutes / Q000737:chemistry*; D004868:Equipment Failure; D006801:Humans; D008422:Materials Testing; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D016062:Porosity; D019736:Prostheses and Implants; D012886:Skull / Q000601:surgery*; D013314:Stress, Mechanical; D013499:Surface Properties
D018786:Bone Substitutes; D019904:Polymethyl Methacrylate