title: Guided bone regeneration (GBR) using membranes and calcium sulphate after apicectomy: a comparative histomorphometrical study.
abstract: OBJECTIVE
  The purpose of the present study was to evaluate the effects of resorbable and non-resorbable membranes, and calcium sulphate on bone regeneration in osseous defects in conjunction with apicectomy.
  
  
  METHODS
  The mandibular third and fourth premolars of 12 beagle dogs were root treated, and apicectomies were performed. The osseous defects were divided randomly into five groups. In groups A, B and C the osseous defects were covered with e-PTFE membranes, PLGA membranes, and collagen membranes, respectively. In group D, defects were filled with calcium sulphate. Nothing was used in group E, which served as controls. The dogs were sacrificed 4, 8, and 16 weeks after the surgery. Undemineralized sections were obtained and evaluated histomorphometrically.
  
  
  RESULTS
  Newly formed cortical bone had closed the defect in the cortical plate in all groups at 16 weeks. The degree of concavity of the new cortical bone at 16 weeks in groups A and D was significantly less than in group B (P < 0.01). The percentage of regenerated bone in group A was significantly greater than in groups B (P < 0.01), C (P < 0.05) and E (P < 0.05). In group D, it was significantly greater than in groups B (P < 0.01) and E (P < 0.05).
  
  
  CONCLUSIONS
  The data suggests that e-PTFE membrane is more effective compared to resorbable membranes and controls for bone regeneration after apicectomy, and that calcium sulphate could be substituted for e-PTFE membrane.
authors: Department of Restorative Sciences, Graduate School, Tokyo Medical and Dental University, Japan. g.yoshikawa.endo@tmd.ac.jp
authors: G
authors: G
authors: Yoshikawa
authors: Y
authors: Y
authors: Murashima
authors: R
authors: R
authors: Wadachi
authors: N
authors: N
authors: Sawada
authors: H
authors: H
authors: Suda
mesh_terms: D020341:Absorbable Implants; D000704:Analysis of Variance; D000818:Animals; D001047:Apicoectomy; D001672:Biocompatible Materials; D001861:Bone Regeneration / Q000187:drug effects*; D002133:Calcium Sulfate / Q000494:pharmacology*; D003094:Collagen; D003764:Dental Materials / Q000494:pharmacology*; D004285:Dogs; D016557:Guided Tissue Regeneration, Periodontal / Q000379:methods*; D007091:Image Processing, Computer-Assisted; D019344:Lactic Acid; D008567:Membranes, Artificial; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers; D011138:Polytetrafluoroethylene; D011897:Random Allocation
chemical_list: D001672:Biocompatible Materials; D003764:Dental Materials; D008567:Membranes, Artificial; D011108:Polymers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D011138:Polytetrafluoroethylene; D003094:Collagen; D002133:Calcium Sulfate