title: Periodontal repair in surgically created intrabony defects in dogs: influence of the number of bone walls on healing response.
abstract: BACKGROUND
  The objective of this study was to histologically evaluate periodontal healing following flap surgery in intrabony periodontal defects to determine the influence of the number of bone walls on periodontal regeneration.
  
  
  METHODS
  One-, 2-, and 3-wall intrabony periodontal defects were surgically produced at the proximal aspect of mandibular premolars in either right or left jaw quadrants in six beagle dogs. Mucoperiosteal flaps were positioned and sutured to their presurgery position following defect preparation. The animals were euthanized at 8 weeks post-surgery, and block sections of the defect sites were collected for histologic and histometric analysis.
  
  
  RESULTS
  Bone and cementum regeneration was positively correlated to the number of bone walls limiting the intrabony periodontal defects. The junctional epithelium averaged (+/- SD) 1.5 +/- 0.2, 1.2 +/- 0.3, and 0.9 +/- 0.2 mm for the 1-, 2-, and 3-wall defects, respectively, with the 3-wall defects being significantly different from the 1-wall defects (P <0.05). Cementum regeneration averaged 1.2 +/- 0.6, 2.0 +/- 0.6, and 2.8 +/- 0.5 mm for the 1-, 2-, and 3-wall defects, respectively; all groups were significantly different from each other (P <0.05). Bone regeneration averaged 1.5 +/- 0.5, 1.7 +/- 0.6, and 2.3 +/- 0.5 mm for the 1-, 2-, and 3-wall defects, respectively, with the 3-wall defects being significantly different from the 1-wall defects (P <0.05).
  
  
  CONCLUSIONS
  The results suggest that the number of bone walls is a critical factor determining treatment outcomes in intrabony periodontal defects. One- and 3-wall intrabony defects appear to be reproducible models to evaluate candidate technologies for periodontal regeneration.
authors.affiliation: Department of Periodontology, Research Institute for Periodontal Regeneration, Oral Science Research Center, College of Dentistry, Yonsei University, Seoul, Korea.
authors.forename: Chang-Sung
authors.initials: CS
authors.lastname: Kim
authors.forename: Seong-Ho
authors.initials: SH
authors.lastname: Choi
authors.forename: Jung-Kiu
authors.initials: JK
authors.lastname: Chai
authors.forename: Kyoo-Sung
authors.initials: KS
authors.lastname: Cho
authors.forename: Ik-Sang
authors.initials: IS
authors.lastname: Moon
authors.forename: Ulf M E
authors.initials: UM
authors.lastname: Wikesjö
authors.forename: Chong-Kwan
authors.initials: CK
authors.lastname: Kim
mesh_terms: D016301:Alveolar Bone Loss / Q000473:pathology* / Q000601:surgery; D000539:Alveolar Process / Q000473:pathology; D000541:Alveolectomy; D000818:Animals; D001861:Bone Regeneration / Q000502:physiology; D003739:Dental Cementum / Q000473:pathology; D004285:Dogs; D004846:Epithelial Attachment / Q000473:pathology; D008334:Mandible / Q000473:pathology / Q000601:surgery; D012038:Regeneration / Q000502:physiology; D013524:Surgical Flaps / Q000473:pathology; D019237:Tooth Cervix / Q000473:pathology; D014092:Tooth Root / Q000473:pathology; D016896:Treatment Outcome; D014945:Wound Healing / Q000502:physiology