title: Effect of guided tissue regeneration on newly formed bone and cementum in periapical tissue healing after endodontic surgery: an in vivo study in the cat.
abstract: BACKGROUND
  The purpose of this study was to evaluate the influence of anorganic bovine bone as a grafted biomaterial on newly formed bone and cementum in periapical regions after surgical endodontic treatment in cats.
  
  
  METHODS
  After inducing apical periodontitis in 9 cats, root canal and surgical endodontic treatment were performed on 72 roots of first and second maxillary premolars. Bone defects were treated with biomaterial particles + a membrane, biomaterial only, a membrane only, or left unfilled (control). Histomorphometry on nondecalcified sections were performed at 3 and 6 months after surgery. Analysis of variance with repeated measures was used within 2 and 3 subject factors to analyze newly formed bone, cementum, biomaterial conduction, and resorption.
  
  
  RESULTS
  At each time period, bone formation was greater at the grafted membrane-protected sites than in the grafted-unprotected sites. At 6 months, the bone area fraction at membrane nongrafted sites was greater than in the grafted-protected sites. The new cementum was significantly greater at 6 months than at 3 months and greater at the grafted membrane-protected sites over the unprotected ones at 6 months. Statistically, the grafted biomaterial, the membrane, and the time contributed significantly to the amount of new bone (P<.05) with no significant interaction. Biomaterial osteoconduction was significantly affected by the time. All 3 variables showed a significant interaction on new cementum.
  
  
  CONCLUSIONS
  There was significantly more bone formation after surgical endodontic treatment when membrane and bone grafts were used as compared with bone grafts only or unfilled control sites. However, it appears that the key factor to the enhanced tissue regeneration is the membrane and not the grafted biomaterial.
authors.affiliation: Department of Periodontology, The Maurice and Gabriela School of Dental Medicine, Tel Aviv University, Tel Aviv, Israel. zviartzi@tau.ac.il
authors.forename: Zvi
authors.initials: Z
authors.lastname: Artzi
authors.forename: Nadav
authors.initials: N
authors.lastname: Wasersprung
authors.forename: Miron
authors.initials: M
authors.lastname: Weinreb
authors.forename: Marius
authors.initials: M
authors.lastname: Steigmann
authors.forename: Hari S
authors.initials: HS
authors.lastname: Prasad
authors.forename: Igor
authors.initials: I
authors.lastname: Tsesis
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D001047:Apicoectomy / Q000379:methods; D001641:Bicuspid / Q000473:pathology / Q000601:surgery; D018786:Bone Substitutes / Q000627:therapeutic use; D002415:Cats; D002417:Cattle; D025021:Cementogenesis / Q000502:physiology*; D003094:Collagen; D003739:Dental Cementum / Q000473:pathology; D017886:Durapatite / Q000627:therapeutic use; D005260:Female; D016557:Guided Tissue Regeneration, Periodontal / Q000379:methods*; D008437:Maxilla / Q000473:pathology / Q000601:surgery; D008567:Membranes, Artificial; D010012:Osteogenesis / Q000502:physiology*; D010485:Periapical Periodontitis / Q000601:surgery*; D010486:Periapical Tissue / Q000473:pathology / Q000503:physiopathology; D012184:Retrograde Obturation / Q000379:methods; D012390:Root Canal Therapy / Q000379:methods; D013997:Time Factors; D014945:Wound Healing / Q000502:physiology
chemical_list: D018786:Bone Substitutes; D008567:Membranes, Artificial; D003094:Collagen; D017886:Durapatite