title: Guided tissue regeneration with bioabsorbable barriers. II. Long-term results in infrabony defects.
abstract: BACKGROUND
  The aim of this 5-year randomized controlled clinical trial was to evaluate the long-term results after guided tissue regeneration (GTR) therapy of infrabony defects using two bioabsorbable barriers.
  
  
  METHODS
  Fifteen pairs of contralateral infrabony defects in 15 patients with moderate to severe periodontitis were treated. Each patient received one polydioxanon (test: T) and one polylactide acetyltributyl citrate (control: C) barrier by random assignment. At baseline, 12, and 60 +/- 3 months after surgery clinical parameters and standardized radiographs were obtained. Vertical bone levels (PBL-V) were measured during surgery and 60 +/- 3 months later by transgingival bone sounding.
  
  
  RESULTS
  Thirteen patients were available for the 60-month examinations. Twelve and 60 +/- 3 months after GTR, statistically significant (P< or =0.001) vertical attachment (CAL-V) gain was found in both groups (T12: 3.5 +/- 1.5 mm; T60: 2.2 +/- 1.8 mm; C12: 4.0 +/- 0.9 mm; C60: 2.4 +/- 1.0 mm). However, from 12 to 60 months after therapy both groups experienced significant CAL-V loss (P<0.05): two defects in the test group and three in the control group had CAL-V loss >2 mm compared to the 12-month reexamination. Twelve and 60 +/- 3 months after surgery, statistically significant (P<0.05) radiographic bony fill was found in both groups (T12: 1.2 +/- 1.3 mm; T60: 1.5 +/- 2.2 mm; C12: 0.9 +/- 1.4 mm; C60: 1.0 +/- 1.6 mm). Further, 60 months after surgery significant (P<0.05) PBL-V gain was found in both groups (test: 1.8 +/- 2.3 mm; control: 2.2 +/- 1.8 mm). The study failed to show statistically significant differences between test and control regarding CAL-V and PBL-V gain 60 months after surgery.
  
  
  CONCLUSIONS
  CAL-V gain achieved after GTR therapy in infrabony defects using both bioabsorbable barriers was stable after 5 years in 21 of 26 defects (81%).
authors.affiliation: Section of Periodontology, Department of Conservative Dentistry, Clinic for Oral, Dental, and Maxillofacial Diseases, University Hospital Heidelberg, Heidelberg, Germany. peter_eickholz@med.uni-heidelberg.de
authors.forename: Peter
authors.initials: P
authors.lastname: Eickholz
authors.forename: Diana-Maria
authors.initials: DM
authors.lastname: Krigar
authors.forename: Bernadette
authors.initials: B
authors.lastname: Pretzl
authors.forename: Harald
authors.initials: H
authors.lastname: Steinbrenner
authors.forename: Christof
authors.initials: C
authors.lastname: Dörfer
authors.forename: Ti-Sun
authors.initials: TS
authors.lastname: Kim
mesh_terms: D000328:Adult; D016301:Alveolar Bone Loss / Q000601:surgery*; D001861:Bone Regeneration; D005260:Female; D016557:Guided Tissue Regeneration, Periodontal / Q000379:methods* / Q000639:trends; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008567:Membranes, Artificial; D008875:Middle Aged; D010512:Periodontal Index; D010514:Periodontal Pocket / Q000601:surgery*; D018709:Statistics, Nonparametric; D016896:Treatment Outcome
chemical_list: D008567:Membranes, Artificial