Long‐Term Results of Guided Tissue Regeneration Therapy in the Treatment of Class II Furcation Defects: A Randomized Clinical Trial

Background: The purpose of this study was to evaluate the results after guided tissue regeneration (GTR) using a bioabsorbable membrane in Class II furcation defects in mandibular molars over a 24‐month period. Methods: Nine patients with 2 comparable Class II furcation defects were included. The defects in each patient were randomly assigned to either test (GTR) or control (open flap debridement) group. Clinical measurements and standardized radiographs were taken at baseline, and at 6, 12, 18, and 24 months. The radiographs were analyzed by subtraction radiography. Results: There were significant probing depth reductions for both test and control groups (P