title: Poly(trimethylene carbonate)-based composite materials for reconstruction of critical-sized cranial bone defects in sheep.
abstract: OBJECTIVE
  The use of ceramic materials in repair of bone defects is limited to non-load-bearing sites. We tested poly(trimethylene carbonate) (PTMC) combined with β-tricalcium phosphate or biphasic calcium phosphate particles for reconstruction of cranial defects.
  
  
  METHODS
  PTMC-calcium phosphate composite matrices were implanted in cranial defects in sheep for 3 and 9 months. Micro-computed tomography quantification and histological observation were performed for analysis.
  
  
  RESULTS
  No differences were found in new bone formation among the defects left unfilled, filled with PTMC scaffolds, or filled with either kind of PTMC-calcium phosphate composite scaffolds. Porous β-TCP scaffolds as control led to a larger amount of newly formed bone in the defects than all other materials. Histology revealed abundant new bone formation in the defects filled with porous β-TCP scaffolds. New bone formation was limited in defects filled with PTMC scaffolds or different PTMC-calcium phosphate matrices. PTMC matrices were degraded uneventfully. New bone formation within the defects followed an orderly pattern.
  
  
  CONCLUSIONS
  PTMC did not interfere with bone regeneration in sheep cranial defects and is suitable as a polymer matrix for incorporating calcium phosphate particles. Increasing the content of calcium phosphate particles in the composite matrices may enhance the beneficial effects of the particles on new bone formation.
authors.affiliation: University of Groningen, University Medical Center Groningen, Department of Biomedical Engineering (FB40), A. Deusinglaan 1, 9713 AV, Groningen, The Netherlands. Electronic address: ytzengni@163.com.
authors.forename: Ni
authors.initials: N
authors.lastname: Zeng
authors.affiliation: University of Groningen, University Medical Center Groningen, Department of Oral and Maxillofacial Surgery, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands. Electronic address: leeuwiaan@gmail.com.
authors.forename: Anne C
authors.initials: AC
authors.lastname: van Leeuwen
authors.affiliation: University of Groningen, University Medical Center Groningen, Department of Biomedical Engineering (FB40), A. Deusinglaan 1, 9713 AV, Groningen, The Netherlands; MIRA Institute for Biomedical Technology and Technical Medicine, Faculty of Science and Technology, Department of Biomaterials Science and Technology, University of Twente, PO Box 217, 7500 AE, Enschede, The Netherlands. Electronic address: d.w.grijpma@utwente.nl.
authors.forename: Dirk W
authors.initials: DW
authors.lastname: Grijpma
authors.affiliation: University of Groningen, University Medical Center Groningen, Department of Oral and Maxillofacial Surgery, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands. Electronic address: r.r.m.bos@umcg.nl.
authors.forename: Ruud R M
authors.initials: RR
authors.lastname: Bos
authors.affiliation: University of Groningen, University Medical Center Groningen, Department of Biomedical Engineering (FB40), A. Deusinglaan 1, 9713 AV, Groningen, The Netherlands. Electronic address: roel.kuijer@gmail.com.
authors.forename: Roel
authors.initials: R
authors.lastname: Kuijer
mesh_terms: D000818:Animals; D001860:Bone Plates; D004146:Dioxanes / Q000627:therapeutic use*; D005260:Female; D011108:Polymers / Q000627:therapeutic use*; D019651:Plastic Surgery Procedures / Q000295:instrumentation / Q000379:methods*; D012756:Sheep; D012886:Skull / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D055114:X-Ray Microtomography
chemical_list: D004146:Dioxanes; D011108:Polymers; C059299:polytrimethylene carbonate
keywords: Animal study; Calcium phosphate; Ceramic; Composite; Cranial bone defect; Poly(trimethylene carbonate)