title: [Guided bone regeneration by using biodegradable co-polymer membranes in rabbits].
abstract: OBJECTIVE
  To repair long bone segmental defects using biodegradable poly epsilon-caprolactone (PCL) and polylactic acid(PLA) co-polymer membranes, and explore its role and mechanism in guided bone regeneration (GBR).
  
  
  METHODS
  Rabbit radial segmental defects (1.2 cm in length, retain the periosteum) were created in this study, 24 animals were divided into 2 groups. The membranes were used to enclose the defects in experimental group, and no treatment in control group. After 3, 6, and 12 weeks of operation, X-ray, gross and histological examinations were observed.
  
  
  RESULTS
  The bone regeneration of experimental group was better than that of control group. Three weeks after operation, obvious external callus along the membrane were found in experimental group, and bony linking composed of external callus bridge were found in 6 weeks after operation. After 12 weeks of operation, callus bridge outside the membrane and bony reunion inside the membrane were achieved in experimental group. While in control group, typical nonunion was observed after 6 weeks of operation.
  
  
  CONCLUSIONS
  Guided bone regeneration can be achieved by using biodegradable membrane. The defects are repaired by the means of outside membrane callus and relatively late inside membrane callus. The membrane can prevent the ingrowth of fibrous tissue into defect area, thus nonunion are avoid, and keep a high concentration of nutritive elements, also serve as a frame for osteocyte growth to enhance bone healing.
authors.affiliation: Department of Orthopedic Surgery, First Clinical Hospital, Norman Bethun University of Medical Science, Changchun, Jilin, P. R. China 130021.
authors.forename: L F
authors.initials: LF
authors.lastname: Huang
authors.forename: J G
authors.initials: JG
authors.lastname: Liu
authors.forename: X X
authors.initials: XX
authors.lastname: Xu
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D001861:Bone Regeneration; D005260:Female; D017102:Fracture Healing / Q000187:drug effects*; D048091:Guided Tissue Regeneration; D019344:Lactic Acid; D008297:Male; D008567:Membranes, Artificial; D011091:Polyesters; D011108:Polymers; D011817:Rabbits; D011885:Radius Fractures / Q000628:therapy
chemical_list: D008567:Membranes, Artificial; D011091:Polyesters; D011108:Polymers; C016240:polycaprolactone; D019344:Lactic Acid; C033616:poly(lactide)