title: Susceptibility of GTR-regenerated periodontal attachment to ligature-induced periodontitis.
abstract: OBJECTIVE
  This study aimed to compare the susceptibility of guided tissue regeneration (GTR)-regenerated periodontal attachment to ligature-induced periodontitis with that of the pristine periodontium.
  
  
  METHODS
  Periodontal breakdown was produced in four monkeys by the placement of orthodontic elastics around experimental teeth (test teeth). During a flap operation, the root surfaces were scaled and planed, and a notch indicating the apical termination of scaling and root planing was made in the root surface. Following resection of the crowns and endodontic treatment, an e-PTFE membrane was adapted over the roots. Subsequently, the flaps were sutured to complete closure of the wound (submerged). At membrane removal after 5 weeks, the crowns of the contralateral teeth serving as controls were resected, and the roots treated endodontically during a flap operation. Artificial composite crowns were then placed on both test and control roots. After 3 months of tooth cleaning, cotton floss ligatures were placed passively around both test and control teeth for a period of 6 months. Two weeks later the animals were sacrificed.
  
  
  RESULTS
  Histological analysis demonstrated that the instrumented root surfaces of the test teeth were covered by newly formed cementum of the reparative, cellular, extrinsic and intrinsic fiber type, while the cementum on the controls was mainly acellular extrinsic fiber cementum. Histometric assessments demonstrated that similar attachment loss had occurred on test (1.0+/-0.5 mm) and control roots (1.0+/-0.4 mm) during the 6 months of ligature-induced plaque accumulation.
  
  
  CONCLUSIONS
  The results indicate that teeth with a periodontal attachment apparatus formed by GTR is not more susceptible to periodontitis than those with a pristine periodontium.
authors.affiliation: Department of Oral Maxillofacial Surgery, Royal Dental College, University of Aarhus, Denmark. lkostopoulos@odont.au.dk
authors.forename: Lambros
authors.initials: L
authors.lastname: Kostopoulos
authors.forename: Thorkild
authors.initials: T
authors.lastname: Karring
mesh_terms: D000818:Animals; D003739:Dental Cementum / Q000473:pathology / Q000503:physiopathology; D003773:Dental Plaque / Q000503:physiopathology; D012534:Dental Scaling; D004198:Disease Susceptibility; D016557:Guided Tissue Regeneration, Periodontal; D008026:Ligation / Q000295:instrumentation; D008252:Macaca fascicularis; D008567:Membranes, Artificial; D009910:Oral Hygiene; D017622:Periodontal Attachment Loss / Q000473:pathology / Q000503:physiopathology; D010513:Periodontal Ligament / Q000503:physiopathology* / Q000601:surgery; D010514:Periodontal Pocket / Q000473:pathology / Q000503:physiopathology; D010518:Periodontitis / Q000503:physiopathology* / Q000601:surgery; D011138:Polytetrafluoroethylene; D016745:Root Planing; D018709:Statistics, Nonparametric; D013524:Surgical Flaps
chemical_list: D008567:Membranes, Artificial; D011138:Polytetrafluoroethylene