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

Statement of problem. Guided tissue regeneration (GTR) is an efficacious an d 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 outcom es obtained with regeneration in strategically important abutments. Material and methods. Sixteen deep intrabony defects around strategically i mportant abutments in 16 patients were treated according to the principles of GTR. After completion of initial periodontal therapy and placement of lo ng-term provisional fixed partial dentures, nonresorbable membranes were ap plied. Membranes were removed after 6 weeks. All patients remained in a sup ervised recall program. Final fixed partial dentures were placed 1 year aft er surgery. Clinical outcomes were evaluated at 1 year and then 4 to 8 year s after surgery. Results. Clinical attachment level gains of 5.3 +/- 1.8 mm reductions in po cket 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 slightl y 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.