Long-term clinical outcomes of abutments treated with guided tissue regeneration

Statement of problem. Guided tissue regeneration (GTR) is an efficacious and predictable treatment modality for deep intrabony defects around natural teeth and abutments. However, long-term prognosis of abutments treated with regeneration has to be proven. Purpose. This study investigated the long-term stability of clinical outcomes obtained with regeneration in strategically important abutments. Material and methods. Sixteen deep intrabony defects around strategically important abutments in 16 patients were treated according to the principles of GTR. After completion of initial periodontal therapy and placement of long-term provisional fixed partial dentures, nonresorbable membranes were applied. Membranes were removed after 6 weeks. All patients remained in a supervised recall program. Final fixed partial dentures were placed 1 year after surgery. Clinical outcomes were evaluated at 1 year and then 4 to 8 years after surgery. Results. Clinical attachment level gains of 5.3 +/- 1.8 mm reductions in pocket depth (6.1 +/- 2 mm), and increases in the percentage of radiographic bone support (31% +/- 18%) were observed at 1 year. At long term follow-up visits, clinical attachment levels remained stable with respect to 1 year (-0.1 +/- 0.6 mm; P=.4). The percentage of radiographic bone support slightly increased as compared with 1 year (1% +/- 3%, P=.04), and pocket depths (0.8 +/- 0.8 mm, P=.004). Conclusions. This study indicated that tooth support can be gained with GTR and maintained over time in patients recalled regularly.