Infrabony defects 20 years after open flap debridement and guided tissue regeneration.

AIM: Evaluation of 20-year results after open flap debridement (OFD) and guided tissue regeneration (GTR) of infrabony defects in a randomized controlled trial. MATERIALS AND METHODS: In originally 16 periodontitis patients (baseline examination), periodontal surgery was performed in 44 infrabony defects. Polylactide acetyltributyl citrate barriers were randomly assigned to 23 out of these 44 defects (parallel). Ten of these patients (GTR) exhibited a second, contra-lateral defect (OFD) each (split-mouth). At baseline, 12, 120 and 240 +/- 12 months after surgery probing depths, attachment level, bleeding on probing as well was Plaque Index, Gingival Bleeding Index and plaque control record were obtained. RESULTS: Twelve patients contributing 38 defects were available at 240 months. At 12, 120 and 240 +/- 12 months, both groups showed significant (p < 0.01) attachment gain (split-mouth: OFD: 12 months: 4.15 +/- 2.93 mm; 120 months: 3.35 +/- 2.37 mm, 240 months: 3.60 +/- 2.55 mm; GTR: 12 months: 3.50 +/- 2.47 mm; 120 months: 3.90 +/- 2.76 mm, 240 months: 3.80 +/- 2.69 mm; parallel: OFD: 12 months: 3.53 +/- 2.04 mm; 120 months: 3.59 +/- 2.54 mm, 240 months: 3.53 +/- 2.50 mm; GTR: 12 months: 4.07 +/- 2.88 mm; 120 months: 3.13 +/- 2.22 mm, 240 months: 3.13 +/- 2.22 mm). Seven teeth (3 OFD, 4 GTR) were lost. Only 1 patient out of 12 was kept in regular supportive periodontal therapy (SPT) over 20 years. The study failed to show significant attachment gain differences between both groups after 240 months. CONCLUSIONS: Twenty years after OFD and GTR in infrabony defects in a population with lack of regular SPT attachment gains at 12 months after surgery were stable. About 82% of the initially included teeth were still in place.